Arthropods

Madagascar hissing cockroach

2010-01-11T22:11:00.000-08:00

The Madagascar hissing cockroach, also known as the hissing roach or simply hisser, is one of the largest species of cockroach, reaching 2–3 inches at maturity. They are from the island of Madagascar off the African coast, where they can be found in rotting logs.

Unlike most cockroaches, they are wingless. They are excellent climbers and can scale smooth glass. Males can be distinguished from females by their thicker, hairier antennae and the pronounced "horns" on the pronotum. Females carry the ootheca (egg case) internally, and release the young nymphs only after the eggs have hatched. As in some other wood roaches, the parents and offspring will commonly remain in close physical contact for extended periods of time. In captivity, these insects can live 5 years. They feed primarily on vegetable material.

Hissing

The Madagascar cockroach has become a popular pet because of its hissing sound, large size, and appearance. Their nickname, "hissing cockroach", is due to their ability to force gas through the breathing pores (spiracles) found on their abdomen. The Madagascar hissing cockroach is believed to be the only insect that can growl in this exact manner, as most insects that make a "hissing" sound do so by rubbing together various body parts. (Some long-horned beetles, e.g., the Giant Fijian long-horned beetle, can squeeze air out from under their elytra, but this does not involve the spiracles). This hiss takes two forms: the disturbance hiss and the fighting hiss. All cockroaches from the fourth instar (fourth molting cycle) and older are capable of the disturbance hiss. Only males use the fighting hiss; they use it when challenged by other males. This results in one of the males backing down and the fight being over. Males hiss more often than females.

Associations with other animals

The mite species Gromphadorholaelaps schaeferi lives on this species of roach and takes some of its host's food. As these mites do not harm the cockroaches they live upon, they are commensals, not parasites.

Popular culture

The hisser has featured in Hollywood movies, prominently in Bug (1975) as roaches who could set fires by rubbing their legs together, and in Damnation Alley (1977) as post-nuclear-war mutant armor-plated "killer" cockroaches. In Starship Troopers, a movie about a war against an enemy called "The Bugs," a teacher is shown encouraging her students to step on this species as part of a TV propaganda broadcast.

A Madagascar hissing cockroach has been used as the driver of a mobile robot. They have been encrusted with Swarovski crystals and used as necklaces and brooches. They were used in the reality television series Fear Factor. The species also made an appearance in the movie Men In Black in 1997. This was later parodied in the comedy Team America: World Police (2004), where a Madagascar hissing cockroach emerges from Kim Jong-il's body after his death, enters a tiny spaceship, and flies away.

In September 2006, amusement park Six Flags Great America announced it would be granting unlimited line-jumping privileges for all rides to anyone who could eat a live Madagascar hissing cockroach as part of a Halloween-themed FrightFest. Furthermore, if a contestant managed to beat the previous world record (eating 36 cockroaches in 1 minute), he would receive season passes for four people during the 2007 season. This is a difficult record to break because raw cockroaches contain a mild neurotoxin that numbs the mouth and makes it difficult to swallow^{[citation needed]}. The promotion ended on October 29, 2006.

The roaches were used in a runway challenge for the sixth cycle of America's Next Top Model.

As pets

Madagascar cockroaches can be kept as pets. They cannot fly like some species of roaches, and they are not aggressive and do not bite. They need a small living area and a spot for them to hide because they do not like the light. The living area must be tested to see if they can climb it as they can climb most kinds. Fish tanks with screens work best but it is also wise to coat the first few inches with petroleum jelly to keep them from getting out. They can live on fresh vegetables along with any kind of pellet food that is high in protein, such as dry dog food. In the USA, some states require permits before this species can be kept as a pet or in breeding colonies. For example, the state of Florida requires such a permit. In fact, during outreach programs, the University of Florida's Department of Entomology and Nematology, which has such a permit, allows only males to be taken out of the laboratory. This is to prevent the possible introduction of a gravid female into the environment.

Anthia sexguttata

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Anthia sexguttata, or the Six-spot ground beetle, is a beetle of the Family Carabidae.

Appearance

Adults measure approximately 4 cm (1.5 inches), are black with six relatively large, white, dorsal spots (four over the elytra and two on the thorax).

Distribution

The species occurs in the drier parts of South Asia.

Diet

Adult A. sexguttata feed on other insects and snails.

Defence

Adults have the ability to squirt an irritating liquid.

Strawberry land hermit crab

2010-01-11T22:06:00.000-08:00

The strawberry land hermit crab is a species of terrestrial hermit crab.

Distribution

C. perlatus is native to the Indo-Pacific region, specifically Madagascar, Japan, and Australia and in other areas around the Red Sea and the Pacific. However, they have spread to other Atlantic regions because humans have brought them there.

In Australia they are restricted to islands and coral cays of the Great Barrier Reef where they have been found to scavenge on sea terns, tortoise eggs and other crabs.

Description

These hermit crabs are noted for their bright red colouring and white granual markings. They can be 18 mm in length.

Juveniles are white with red antennae, but as they grow and moult, their orange and red colouring appears. During their younger years, they are more of a pale red or orange colour. As adults, they are very red. Their eyestalks are the same colour as their body and are thick. Their walking legs are thick and strong for climbing.

Coenobita perlatus has 4–7 pronounced striations on the large pincer in a pattern similar to Coenobita rugosus and to a lesser extent Coenobita compressus.

As a pet

Like all hermit crabs, it prefers gastropod shells with a round, uninterrupted aperture such as Turbo shells.

They are most active at a relative humidity of about 80% and a temperature of about 80 °F (27 °C).

They can live for around 30 years in the wild. In captivity they have been known to live for about 32 years.

Sea-Monkeys

2010-01-11T22:05:00.000-08:00

Sea-Monkeys are a novelty animal sold to children in the United States and the United Kingdom since 1960. They are a variant of brine shrimp or Artemia salina, a species which enters cryptobiosis, a natural state of suspended animation, allowing their cysts (dormant saclike embryos) to be sold as a dry powder. When the powder is poured into water, live shrimp appear within hours, and can grow up to an adult length of 2 centimeters within one year. Thus the novelty of "instant" life. In the United Kingdom in the 1970s they were also sold as "Artful Arties".

Product description

The purchaser of Sea Monkeys receives three packages, a "water purifier" package, a "food" package, and "instant life eggs" package, along with a set of instructions.

The key ability of unhatched "Sea-Monkeys" to be packaged, shipped, and handled is that they enter cryptobiosis, a natural suspended animation. When released into the prepared aquarium they leave this state and emerge from their cysts. The genetic variant of brine shrimp, the Sea-Monkey, was given the term "instant life" to reflect the instant hatching seen when the cysts are added to the saltwater medium.

To start the process, the "water purifier" package is added to water on the first day. This package has eggs as well as the salt. On the second day, the user adds the "instant life eggs" package, containing Epsom salts, borax and soda ash, in addition to eggs, yeast, and sometimes a blue or green dye. The dye enhances the experience by making the freshly hatched animals more visible.

The Sea-Monkeys seen on the fifth day after adding the "eggs package" are derived from the eggs added with the "purifier" package. The food package is a mixture of Spirulina and dried yeast. The "boost" packages mainly contains salts, which induce increased sexual activity in Artemia.

Taxonomy

They are members of the phylum Arthropoda now called Artemia salina × nyos. They originated in salt lakes and evaporation flats.

Sea-Monkeys are a breed of Artemia salina sometimes classified as a "new species" called "Artemia nyos" ("nyos" being an acronym for "New York Ocean Science Laboratories" where the first "Sea Monkey" Artemia were bred). This is in absence of a formal description fulfilling the ICZN requirements. As such, the correct name would be Artemia salina × nyos if Sea Monkeys are (as is sometimes reported) interspecific hybrids between A. salina and an indeterminate species of Artemia.

History

Sea Monkeys were marketed in 1957 by Harold von Braunhut as Instant Life, though Braunhut changed the name to "Sea-Monkeys" on May 10, 1962. The name "Sea-Monkeys" was chosen because of their supposed playful monkey-like behaviour. Braunhut is also the inventor of X-Ray glasses. They were known for their exaggerated advertisements and packaging, which featured smiling anthropomorphic creatures (originally drawn by Joe Orlando) who bore little resemblance to their true appearance. Underneath was a disclaimer stating, "Caricatures shown not intended to depict Artemia." The present disclaimer on the package states, "Illustration is fanciful, does not depict Artemia nyos."

Sea Monkeys were bred for their larger size and longer lifespan, making them more suitable as pets than the original breed of brine shrimp. The U.S. Patent 3,673,986 granted in 1972 describes this as "hatching brine shrimp or similar crustaceans in tap water to give the appearance of instantaneous hatching."

Many types of Sea-Monkey kits are now available. The company produces the original Ocean View tank as well as a variety of other products. The Sea-Monkeys company is now part of the Educational Insights corporation. As of 2008, Sea Monkeys are a division of Transcience.

Other companies have distributed pets along the Sea-Monkey model, including one by Wham-O, and "The Swarm", a product from Dr. Jordan's formulae. In the late 1970s to early 1980s, sachets of "Sea Monsters" were sold in 25-cent gumball machines at A&P supermarkets. When added to water, the packet's contents provided the eggs, salt and nutrients to hatch the brine shrimp.

More recently, an Australian company, Little Aussie Products, has marketed "Itsy Bitsy Sea Dragons", with a different brine shrimp species, Parartemia zietziana, and other tank "buddies" to live with them.

Pagurus bernhardus

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Pagurus bernhardus is the common marine hermit crab of Europe's Atlantic coasts. It is sometimes referred to as the common hermit crab or soldier crab. It is about 3½ cm long , and is found in both rocky and sandy areas, from the Arctic waters of Iceland, Svalbard and Russia as far south as southern Portugal, but its range does not extend as far as the Mediterranean Sea. It can be found in pools on the upper shore and at the mean tide level down to a depth of approximately 140 m, with smaller specimens generally found higher on the shore and larger individuals at depth. P. bernhardus is an omnivorous detritivore that opportunistically scavenges for carrion and which can also filter feed when necessary.

Pagurus bernhardus uses shells of a number of gastropod species for protection, including Littorina littorea, Littorina obtusata, Nucella lapillus and Buccinum. In the warmer parts of its range, the sea anemone Calliactis parasitica is often found growing on the shell occupied by Pagurus bernhardus. In colder waters, this rôle is filled by Hormathia digitata.

Notostraca

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Members of the order Notostraca are small crustaceans in the class Branchiopoda. Triops have two internal compound eyes and one naupliar eye in-between, a flattened carapace covering its head and leg-bearing segments of the body. The order contains a single family, with only two extant genera. Their external morphology has apparently not changed since the Triassic appearance of Triops cancriformis around 220 million years ago. Triops cancriformis may therefore be the "oldest living animal species on earth." The members of the extinct order Kazacharthra are closely related, having been descended from notostracans.

Characteristics

Although notostracans are related to fairy shrimps, they differ greatly in structure. The flat oval shield covers the crustacean's head and the front part of the thorax. Near the front edge of the shield, on its surface, is a small lump that bears two dark, stalkless, compound eyes. In between them is an unpaired naupliar eye, and behind the three eyes is an unusual four-celled organ. The function of this organ is uncertain. It is thought to be an internal secretion organ. The hind edge of the shield is a semicircular dent that leaves the hind portion of the thorax exposed. The abdomen ends with a telson that bears two long segmented uropods, known as furcae.

By looking at a tadpole shrimp from the ventral side one can clearly see the structure of its segments and limbs. In front, the carapace curves down to the ventral side, where it attaches to a large labrum (upper lip) that is almost square in shape. The first and second pair of antennae is extremely reduced in size, while the mandibles are quite large, with many toothlike projections. The mouth is located in between the mandibles, behind the labrum. Behind the mandibles are one or two pairs of flat jaws (maxillae). The next 10 thoracic segments each bear a pair of legs. As in fairy shrimps, the legs have 6 lobes on the inner side that push the food towards the mouth; on the outer side is one large swimming lobe and one breathing lobe, modified into a gill (fairy shrimps have two breathing lobes on each leg). Detailed muscle studies conclude that the legs of tadpole shrimps and fairy shrimps have no phylogenetic relationship, apparently having evolved independently, albeit with similar functions.

The first and, less obviously, second pair of a tadpole shrimp's legs differs from other legs by the four inner lobes, which are modified into elongated, segmented, flagellum-like structures that project outside from the edge of the carapace. They act as sensory organs and even resemble externally the flagella of the antennae of other crustaceans. This modification of the inner lobes of the front thoracic legs is unquestionably associated with the reduction of the tadpole shrimp antennae.

In females, the eleventh pair of limbs is quite unusual in structure: the large outer lobe, which is used for swimming in other limbs, is modified into a round egg capsule, where the eggs are carried. In males, the eleventh pair of legs does not differ from the other legs.

There is another surprising phenomenon in the structure of tadpole shrimps. Every thoracic segment, from the thirteenth one on, bears not one, but 4 to 6 pairs of legs. Therefore, the number of pairs of the crustacean's legs often reaches as many as 70. No other crustacean has as many legs as tadpole shrimps.

The legs gradually become smaller from front to back, while the posterior-most segments bear no legs at all.

An obvious difference between tadpole shrimp and fairy shrimp legs is that the former possess several spikes at the base of each front leg, pointing inward. Tadpole shrimps use the spikes to grab large food particles and pass it from one leg to another forward, to the mouth. While fairy shrimps filter small food particles suspended in the water, notostracans apparently cannot do this. Their hind limbs mostly aid in respiration. It is quite noticeable during the crustacean's brief stops that its rear limbs continue moving, while the front ones keep still. As a tadpole shrimp swims, its legs bend and straighten in a wavelike motion. The Swedish zoologist Lundblad once droppered some water mixed with carmine near a tadpole shrimp's hind legs. He observed as the water moved slowly forward through the groove between the crustacean's hind legs. However, as soon as the water reached the tenth pair of legs, it streamed forward steadily, which showed how important the front limbs are in the process of bringing food up to the mouth.

When a tadpole shrimp swims, its eyesight plays an important role. Lighting up the bottom of an aquarium in a dark room makes the crustacean roll over, ventral side up: the dorsally positioned eyes can then sense the light. Even when the crustacean's eyes are lacquered and it sits on the bottom of the aquarium ventral side down, the experiment brings the same result. Apparently, the tadpole shrimp reacts to the light because the naupliar eye compartment continues down as a connective passage and ends at the ventral side, in front of the upper lip, as a pigmentless "window". Thus, tadpole shrimps can sense light from above and below, simultaneously.

Notostracans do not use their eyes to find food. They use a special chemical sense, centred in the flagellum-like inner outgrowths on the first pair of legs. A tadpole shrimp can easily find an earthworm in an aquarium and eat it. However, studies show that when quinine is added to the worm, the crustacean feels the serving with its flagella and refuses to eat the distasteful food.

Life cycle

In the northern hemisphere, tadpole shrimps mainly hatch from unfertilized eggs. The populations of the North American and Eurasian puddles and pools are made up almost exclusively of females. There is often less than 1 male per 100 females, and some pools contain no males at all. As one travels north to south, however, the males increase in numbers; in the tropics they may even outnumber the females.

Due to the rareness of the males in most species, mating tadpole shrimp are rarely observed. When mating, the male attaches to the female and swims in an upside-down position with the female held above. The female keeps the fertilized eggs in a brood pouch for a short time after mating before releasing them.

These tiny eggs are equipped with a strong, thick shell. They can withstand freezing and drought, and can hatch as long as 25 years after release. The eggs can stand temperatures of up to 80°C, or pass through a frog's intestine without any harm at all. They are easily carried by the wind, even for very long distances. Due to these qualities of their eggs, tadpole shrimps are common around the world.

If the egg arrives in a pool with suitable conditions, the larva hatches a year later. In the common species Triops cancriformis this larva is a typical nauplius, with three pairs of limbs and no traces of segmentation. In other tadpole shrimp species the larva hatches at a later stage - the metanauplius, characterized by a segmented hind part of the body. In order to reach sexual maturity, Triops cancriformis must moult about 40 times. These moults follow one another very quickly and at summer temperature, the development from a nauplius to an adult crustacean takes only about two weeks. The spring tadpole shrimp (Lepidurus apus) reaches a length of 12 mm after 17 moults, while the sexual dimorphism appears after the 14th moult.

The maximum life spans in the lab agree with data from field observations on Triops survival. In the lab, T. longicaudatus has a maximum lifespan of about 50 days and T. cancriformis a maximum lifespan of about 90 days, with some individuals beginning to die off as soon as two weeks after hatching. Secondarily, some may suffer premature deaths from moulting complications or other reasons.

Notostracans in the aquarium

Notostracans, primarily Triops longicaudatus, are often sold to children in small packets as eggs as an interesting science project or as a beginner's kit for their first aquarium.They first have to keep the triops in water at a temperature of 22-29 degrees celsius. One then pours distilled or spring water onto the eggs, and they will hatch out very quickly--often within less than a day. They will also grow at a remarkable pace; growth is actually noticeable from one day to the next until they reach their maximum size of approximately 2 inches(6 cms), including their caudal appendages. If food is not in abundance--and sometimes even if it is--they will not hesitate to eat each other.

These creatures can make a useful addition to a freshwater aquarium, as they keep the substrate very clean and eat almost anything they find. They may, however, pose a slight threat to very small fish or other crustaceans, and may in turn be the prey of larger fish. Also, they may damage the roots of aquarium plants they encounter if not kept well fed. They are also very short-lived pets, but are easily replaceable.

By thoroughly drying the tank in which they are kept after a die-off and then allowing the completely dry tank to sit for at least a month and finally reflooding it with distilled or spring water, another generation of pets is easily generated, as the previous brood will have left eggs in the substrate. This simulates the periodic drying and flooding of the natural habitat of the tadpole shrimp.

Pop culture references

They Might Be Giants have a song entitled "Triops Has Three Eyes" on their children's album "Here Come the 123s." The CD/DVD also has a video for the song, which features a cartoon triops dancing throughout. The song was also included in their weekly kids podcast on 4/18/2008

Marmorkrebs

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Marmorkrebs or marbled crayfish are parthenogenetic crayfish that were discovered in the pet trade in Germany in the 1990s. The location of natural populations (if any) of this species is unknown. Information provided by one of the original pet traders as to where they were obtained was deemed "totally confusing and unreliable". Nevertheless, Marmorkrebs appear to be closely related to North American crayfish in the genus Procambarus that are sold as pets rather than European crayfish, suggesting that they are not native to Europe. This species currently has no formal scientific name.

Marmorkrebs are the only known decapod crustaceans to reproduce by parthenogenesis. All individuals are female. Offspring are genetically identical to the parent, indicating they reproduce by apomixis. Because Marmorkrebs are genetically identical, easy to care for, and reproduce at high rates, they are a potential model organism, particularly for studying development.

Marmorkrebs have been found in the wild in Germany, Italy and Madagascar, probably through release or escape from aquaria. Because Marmorkrebs reproduce at high rates, and given the history of invasive species that were introduced through the pet trade, there has been substantial concern that Marmorkrebs are a potential pest species. Marmorkrebs can survive fairly low temperatures, which would allow them to overwinter in Europe

Hermit crab

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Hermit crabs are decapod crustaceans of the superfamily Paguroidea. They are not closely related to true crabs. Hermit crabs are quite commonly seen in the intertidal zone: for example, in tide pools.

Most species have long, soft abdomens which are protected from predators by a salvaged empty seashell carried on the crab's back, into which the crab's whole body can retract. Most frequently hermit crabs use the shells of sea snails; the tip of the hermit crab's abdomen is adapted to clasp strongly onto the columella of the snail shell. As the hermit crab grows in size, it has to find a larger shell and abandon the previous one. This habit of living in a second hand shell gives rise to the popular name "hermit crab", by analogy to a hermit who lives alone.

Of about five hundred known species, most are aquatic and live in varying depths of saltwater, from shallow reefs and shorelines to deep sea bottoms. However, tropical areas host some terrestrials. Some of these are quite large, such as Petrochirus diogenes.

The king crabs in the family Lithodidae were formerly considered to be derived hermit crabs, but are now placed in a separate superfamily.

Development and reproduction

Hermit crab species range in size, shape, from species with a carapace only a few millimetres long to Coenobita brevimanus which can approach the size of a coconut. The shell-less hermit crab Birgus latro is the world's largest terrestrial invertebrate. Hermit crabs left abdomen tells you the gender, they have holes in the abdomen. Larger holes means female, smaller holes mean male.

The male's reproductive organs are located near and just below the heart and open to the outside at the base of the hindmost pair of walking legs. In the female, they are located at the base of the middle pair of walking legs. Females usually lay their eggs shortly after copulating, but they can also store sperm for many months. The eggs become fertilised as they passing through the chamber holding the sperm just before laying. The mother carries the eggs in a mass attached to her abdomen inside the shell. The number of eggs is usually large, but depends on the animal's size.

The young develop in stages, with the first two (the nauplius and protozoea) occurring inside the egg. Most hermit crab larvae hatch at the third stage, the zoea. This is a larval stage wherein the crab has several long spines, a long narrow abdomen, and large fringed antennae. After several zoeal moults, this is followed by the final larval stage, the megalopa stage.

Terrestrial hermit crabs begin life in the sea, but become air-breathers via moulting. After the final developmental moult, the youngster must live mostly on land. Its link with the sea is never entirely broken however, because it always carries a small amount of water in its shell to moisten its abdomen and hydrate its modified gills.

Juvenile land hermit crabs move away from the water. They then grow and develop through moulting in which they shed their exoskeleton. During moulting, they are extremely vulnerable and inactive, and usually burrow in the ground for protection. The new exoskeleton hardens and the crab regenerates lost or broken claws or legs in around 10 days. A hermit crab can moult as often as every other month when young, and every 18 months when they are older.

Hermit crabs release their eggs in the ocean, near the shore. Because of this, it is very hard to breed hermit crabs in captivity. Little is known about reproduction in captivity. E.g., whether seasonal changes contribute to the animals' mating patterns. Some studies suggest that captive males become more sexually interested if they have brightly colored shells, possibly increasing their self-confidence. Breeding requires near-perfect conditions and even then, after the eggs hatch, they may die from inappropriate food and water.

Fossil record

The fossil record of in situ hermit crabs using gastropod shells stretches back to the Late Cretaceous. Before that time, at least some hermit crabs used ammonites' shells instead, as shown by a specimen of Palaeopagurus vandenengeli from the Speeton Clay, Yorkshire, UK from the Lower Cretaceous.

Hermit crabs as pets

Several marine species of hermit crabs are common in the marine aquarium trade. Of the approximately 15 terrestrial species in the world, the following are commonly kept as pets: Caribbean hermit crab, Coenobita clypeatus, Australian land hermit crab Coenobita variabilis, and the Ecuadorian hermit crab, Coenobita compressus. Other species such as Coenobita brevamanus, Coenobita rugosus, Coenobita perlatus or Coenobita cavipes are less common but growing in availability and popularity as pets. Hermit crab pets also require certain habitat conditions to be able to thrive. The list is as follows:

Humidity gauges (humidity: 75-85% relative)
Temperature gauges (temperature: 70-80°F)
Substrate: sand, coconut fiber (must be deep and diggable for moulting)
Minimum of a 5 gallon tank for one crab; 10 gallon tank for about 2 crabs
Separate moulting tank^{[dubious – discuss]}
Fresh water dish
Salt water pool for submerging (aquarium salt)

These omnivorous or herbivorous species can be useful in the household aquarium as scavengers, because they eat algae and debris.

Hermit crabs were once seen as a "throwaway pet" that would live only a few months, but species such as Coenobita clypeatus has a 23 year lifespan if properly treated and some have lived longer than 32 years.

In general, and despite their moniker, hermit crabs are social animals that do best in groups. They also require a temperature and humidity-controlled environment, and adequate substrate to allow them to bury themselves while moulting.To breed hermit crab you need a outside tank with a mini like beach.they need water at 70-80 dergees.they will take off their shell to breed.you should watch them in the hotwater.the eggs change color in the water

Geosesarma

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Geosesarma is genus of terrestrial crabs. They live and reproduce on land with its larval stage inside the egg. Some species such as Geosesarma nemesis are insectivorous and are beneficial to humans. Some species are kept as pets. They were once considered part of the Grapsidae family but were moved out with the other Sesarmidae. Most species of this genus are brightly colored.

Fiddler crab

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A fiddler crab, sometimes known as a calling crab, may be any of approximately 97 species of semi-terrestrial marine crabs within the genus Uca. Belonging to the family Ocypodidae, fiddler crabs are most closely related to the ghost crabs of the genus Ocypode. This crustacean is named for the fiddle-shaped large claw of the male crab. This entire group is composed of small crabs – the largest being slightly over two inches across. Fiddler crabs are found along sea beaches and brackish inter-tidal mud flats, lagoons and swamps.

Like all crabs, fiddler crabs shed their shells as they grow. If they have lost legs or claws during their present growth cycle a new one will be present when they molt. If the large fiddle claw is lost, males will develop one on the opposite side after their next molt. Newly molted crabs are very vulnerable because of their soft shells. They are reclusive and hide until the new shell hardens.

Ecuadorian hermit crab

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The Ecuadorian hermit crab also known as the Pacific hermit crab is a species of land hermit crab. It is one of the two land hermit crabs commonly sold in the United States as a pet, the other being the Caribbean hermit crab (Coenobita clypeatus).

Features and identification

Coenobita compressus is a member of the phylum Arthropoda and the class Malacostraca. They can be up to 12mm in length and are thought to be one the smallest species of land hermit crabs. They have four walking legs, a small pincer, a large pincer, and antennae. Many people who keep these hermit crabs as pets notice that Ecuadorians can be relatively fast walkers, even faster than Caribbean hermit crabs. The eyes of Ecuadorians are more oval-shaped when compared to the round eyes of Caribbean hermit crabs and are thicker. Their big claw has 4 or 5 small ridges on the upper part. The tips of the second pair of walking legs are darker than the rest of the leg. The abdomen of the Ecuadorian hermit crab is short and fat.

Ecuadorian hermit crabs vary greatly in color, some are bright (yellow, dark grey, or orange), but more often they are a tan color. Sometimes they may have a blue or green tint to their bodies or the insides of their legs. They also have comma shaped eyes, unlike the purple pincher species that has dot shaped eyes.

When choosing a shell they tend to give preference to nerite, deshayes, Babylonia, valencienne and other shells with a wider mouth.

Habitats

Native to Ecuador and Chile, these hermit crabs live on the Pacific seashore around the tidal pools and high-tide zone. Their bodies have adapted to this seashore existence and are able to metabolize the salt in seawater.

Like most hermit crabs they are scavengers and will consume seaweed, dead fish and other detritus that washes up on the shore.

Studies

A study with Coenobita compressus conducted by the department of biology at the University of Michigan showed that land hermit crabs prefer the odours of foods that they have not recently eaten. The crabs that were exposed to one food for at least 9 hours preferred foods having other odours for the next 6 hours. It is this short-term avoidance of food (like human beings who get "bored" of the same meals over and over again) that compels the crabs to seek out a wider range of food might be advantageous to the crab, possibly through the consumption of a more nutritionally balanced diet.

Crayfish

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Crayfish, crawfish, or crawdads — members of the superfamilies Astacoidea and Parastacoidea — are freshwater crustaceans resembling small lobsters, to which they are related. They breathe through feather-like gills and are found in bodies of water that do not freeze to the bottom; they are also mostly found in brooks and streams where there is fresh water running, and which have shelter against predators. Most crayfish cannot tolerate polluted water, although some species such as the invasive Procambarus clarkii are more hardy. Crayfish feed on living and dead animals and plants.

In Australia, New Zealand and South Africa, the term crayfish or cray generally refers to a saltwater spiny lobster, of the type Jasus that is indigenous to much of southern Oceania, while the freshwater species are usually called yabby, or koura, from the Indigenous Australian, and Māori, names for the animal respectively.

The study of crayfish is called astacology.

Geographical distribution and classification

There are three families of crayfish, two in the northern hemisphere and one in the southern hemisphere. The southern-hemisphere (Gondwana-distributed) family Parastacidae lives in South America, Madagascar and Australasia, and is distinguished by the lack of the first pair of pleopods. Of the other two families, members of the Astacidae live in western Eurasia and western North America and members of the family Cambaridae live in eastern Asia and eastern North America.

The greatest diversity of crayfish species is found in south-eastern North America, with over 330 species in nine genera, all in the family Cambaridae. A further genus of astacid crayfish is found in the Pacific Northwest and the headwaters of some rivers east of the Continental Divide. Many crayfish are also found in lowland areas where the water is abundant in calcium and oxygen rises from underground springs

Australasia is another centre of crayfish diversity, with over 100 species in a dozen genera. Many of the better-known Australian crayfish are of the genus Cherax, and include the marron (Cherax tenuimanus), red-claw crayfish (Cherax quadricarinatus), yabby (Cherax destructor) and western yabby (Cherax preissii). The world's largest freshwater crayfish, Astacopsis gouldi, which can achieve a mass in excess of 3 kilograms (6.6 lb), is found in the rivers of northern Tasmania.

Madagascar has a single (endemic) crayfish species, Astacopsis madagascarensis.

Europe is home to seven species of crayfish in the genera Astacus and Austropotamobius.

Cambaroides is native to Japan and eastern mainland Asia.

Crayfish as pets

Crayfish are kept as pets in freshwater aquariums. They prefer foods like shrimp pellets or various vegetables but will also eat tropical fish food, regular fish food, algae wafers, and even small fish that can be captured by their claws, such as goldfish or minnows. Their disposition towards eating almost anything will also cause them to consume most aquarium plants in a fish tank; however, crayfish are fairly shy and may attempt to hide under leaves or rocks. When keeping a crayfish as a pet, it is suggested they are provided with a hiding space. At night, some fish become less energetic and settle to the bottom. The crayfish might see this as a chance for an easy meal, or a threat, and injure or kill the fish with its claws. Crayfish are effective scavengers and will consume fish carcasses. They sometimes will consume their old exoskeleton after it has molted. Since crayfish are accustomed to being around ponds or rivers they will have a tendency to shift gravel around on the bottom of the tank, creating mounds or trenches to emulate a burrow. Crayfish will often try to climb out of the tank, especially if an opening exists at the top that they can fit through. Crayfish kept as pets in the U.S. from local waters are usually kept with bluegill or bass rather than goldfish or other tropical/subtropical fish.

However, most species of dwarf crayfish, such as Cambarellus patzcuarensis will not destructively dig or eat live aquarium plants. They are also relatively non-aggressive and can even be kept safely with dwarf shrimp. Because of their very small size of 1.5 inches or less, some fish, such as loaches are often a threat to the crayfish rather than the other way around.

In some nations, such as the United Kingdom, United States, Australia, and New Zealand, imported alien crayfish are a danger to local rivers. The three species commonly imported to Europe from the Americas are Orconectes limosus, Pacifastacus leniusculus and Procambarus clarkii. Crayfish may spread into different bodies of water because specimens captured for pets in one river are often flung back into a different one. There is a potential for ecological damage when crayfish are introduced into nonnative bodies of water (e.g. great crayfish plague in Europe).

Coenobita rugosus

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Coenobita rugosus is a species of land hermit crab native to Australia and the east African coast to the south west Pacific.

Features and identification

C. rugosus has four walking legs, a small pincer, a large pincer, and antennae. When threatened C. rugosus is able to make a 'chirping' sound by rubbing its large pincer against its shell as a stridatory aparatus.

C. rugosus vary in color depending on nutritional intake and common colors include green, brown and tan; but black, white, pink, and blue have also been observed. They can be differentiated from other species of land hermit crabs by the pronounced striations (stitch marks) on their large pincer. Coenobita compressus and Coenobita perlatus also possess these striations to a lesser extent but can easily be distinguished from C. rugosus by size and color; especially in the case of the C. perlatus which is a striking red color as an adult.

They can be 15mm in length and their eyestalks are sandy in color and may have a brown stripe on the bottom of them. The bottom pair of the second antena are light orange in color. Their big claw has 7 ridges on the upper part and there is usually hair on the inside of both claws. On the last pair of walking legs, on the second segment, it is flattened and the color is lighter. The abdomen is short and fat.

As with other species of land hermit crabs C. rugosus are scavengers and will consume plants, dead fish, fruit and other detritus.

Coenobita cavipes

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Coenobita cavipes is a species of land hermit crab native to the eastern parts of Africa, the Philippines, China, Japan, Malaysia, Taiwan, Polynesia, and Micronesia.

They are found in the inland area of forests and only go to the beach for mating. As with other land hermit crabs they are omnivorous scavengers but C. cavipes mainly eat fruit.

The first set of antennae are colored black and the second set red. They also have black hair, white bumps, and a stripe across the large pincer. Their coloring can be orange to dark brown. They have a tendency to moult more often than other crabs.

Sample of a Brown/Concave Land Hermit Crab (C.cavipes) wearing a sinistral land snail shell from Jakarta, Indonesia

They can be 30mm in length. Their eyestalks are black and elongated. The tip of their big claw tends to be white. Their walking legs are slim and the third walking leg is usually very long and slim. Their abdomens are quite long and slender.

They generally give preference to turban shells ( Turbo sp.), tuns ( Tonna sp. ), and Achatina fulica shells.

Coenobita brevimanus

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Coenobita brevimanus is a species of land hermit crab native to the east coast of Africa and the south west Pacific Ocean. Adults of this species can be larger than any other species from the genus Coenobita and only Birgus latro is larger in the family Coenobitidae.

Coenobita

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The genus Coenobita contains about thirteen species of terrestrial hermit crabs. They are able to live on land because of their modified gills, although they still require a warm, humid environment. They can live several miles from water in moist forests and jungles.

Land hermit crabs live in colonies of 100 and more, feeding on plant and animal matter. They are omnivorous scavengers which eat plant and animal matter, including fallen fruit, rotting wood, decaying animals and fish. Land hermit crabs will also eat their old exoskeleton after it has molted. This adds up calcium for its new outer shell.

Coenobita are named after and share a name with the original Latin term for the Cenobitic monastic order, derived from the Greek κοινός and βίος (koinos and bios, meaning "common" and "life"). Cenobitic monks also stress the value of communal living; eremitic monastic orders are those in favour of hermitic lifestyles.

Terrestrial hermit crabs as pets

The land hermit crabs most commonly kept as pets in the United States are the Caribbean hermit crab (Coenobita clypeatus, sometimes called the "purple pincher"), Strawberry Hermit Crab (Coenobita perlatus) and the Ecuadorian hermit crab (Coenobita compressus). Other species such as Coenobita brevimanus, Coenobita rugosus and Coenobita cavipes are slowly becoming equally common. In Australia, the only land hermit crabs kept as pets were the Australian land hermit crab (Coenobita variabilis) and the strawberry land hermit crab (Coenobita perlatus), which are native to Australia, Indonesia and other islands in the Pacific Ocean. They are sold as pets in Australia.

Caribbean hermit crab

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The Caribbean hermit crab, also known as the West Atlantic crab, the tree crab, the soldier crab, and the purple pincher (due to the distinctive purple claw), is a species of land hermit crab native to the west Atlantic, Bahamas, Belize, southern Florida, Venezuela, the Virgin Islands, and the West Indies.

This species is one of the two land hermit crabs commonly sold in the United States as a pet, the other being the Ecuadorian hermit crab. In captivity they can live to be over 30 years old (and over 40 years in exceptional cases).

Caribbean hermit crabs are omnivorous scavengers who live in colonies of 100 or more in inland areas.

As pets they prefer a relative humidity level between 70% and 78%, and a temperature of 24°C (75°F).

Physical description

Coenobita clypeatus is a member of the phylum Arthropoda and the class Malacostraca. The color varies from a pale red to a dark brown or burgundy.

The eyestalks are round and white, with a black or brown stripe on the bottom. The eyes are oval in shape. The abdomen is short and fat. There are four walking legs, four tiny legs to hold the shell in place, a small pincher, a large purple pincher, and four antennae. The large claw is used to close the entrance of the shell to protect itself from predators.

Although these hermit crabs live on land, they have gills, rather than lungs. The high relative humidity of their native environments, plus water carried in the shell, allows their modified gills to remain wet and thus to function properly in extracting oxygen from the air.

Habitat

Adult Caribbean hermit crabs can be found well inland, while juveniles begin their lives in the water and near the shore. They are a common site near homes of people. They burrow and hide under the roots of large trees.

Diet

Caribbean hermit crabs are both herbivorous and scavengers. In the wild, land hermit crabs feed off of coconut trees, leftovers from humans, and scavenge dead organisms, such as fish and other crabs. Hermit crabs are able to bury their food in the sand to consume later, but other crabs may find it and consume it themselves.

In captivity, land hermit crabs are fed commercial foods which come in many varieties. Hermit crabs are also fed treats that include fruits and vegetables such as coconuts, mangos, papayas, apples, bananas, carrots, or spinach.

Shell usage and shell fights

The land hermit crab uses a shell to protect its delicate body. The shell is sometimes that of a land snail when it is young, but is usually that of a marine snail. When a marine snail dies, the soft parts decompose or are eaten and the empty shell often washes up onto the shore. The hermit crab can then find and occupy the shell. Larger shells are necessary as the crab grows, but that growth is quite slow.

Hermit crabs are very particular about their shells. Shell switching is not uncommon as the crab searches for the perfect shell. A desired characteristic of a shell is an opening about the size of the large claw, plus about 2½–3 mm (1/10 in to 1/8 in) all around (more for larger crabs). When threatened, the crab withdraws into the shell and blocks the entrance with the large claw.

Fierce shell fights can occur when the shell supply is not adequate. The loser often dies, since many hermit crabs will not release their grip on their shell until they are torn apart. The loss of limbs in shell fights is common, but may not result in death especially since the hermit crab can choose to drop (autotomize) a limb to disengage from the conflict.

Growth and molting

The Caribbean hermit crab, like all species of hermit crabs, grows through a strenuous and hazardous process called molting where the exoskeleton of the animal is shed and a new, soft exoskeleton is exposed from beneath. A molt also allows the crab to regrow lost appendages. The smallest Caribbean hermit crabs will molt many times per year, while the largest (about the size of a baseball) may only molt once every 12 to 18 months.

Before a molt, the hermit crab will attempt to eat enough to survive the molting period. It will obtain sea salt from salt water to aid in shedding the old exoskeleton and will store a supply of water. The crab may even seek out a smaller, tighter shell for easier digging or a larger shell for room to shed. Normally the molt is started by digging down into the moist substrate (with its shell) and creating a little cave. There total darkness triggers the secretion of the molting hormone ecdysone.

Over a period of up to three months (larger crabs require the most time),

the buried, molting crab sheds the old exoskeleton in a process called ecdysis,
lost appendages may be regrown (completely or partially),
the new exoskeleton hardens,
the old exoskeleton is eaten, in order to reuse the calcium and other lost nutrients while it's molting,
the crab regains its strength and returns to the surface.

Sometimes the land hermit crab will molt on the surface where other crabs may eat the shed exoskeleton or the exposed molting crab. Circumstances that may cause a surface molt include illness, or the lack of a substrate in which the crab can bury itself.

Land hermit crab reproduction

Female land hermit crabs release fertilized eggs into the ocean. The spawning (called "washing" in the English-speaking Caribbean) occurs on certain nights, usually around August. The crabs congregate en masse near certain places (called "soldier wash") on the shore. When night comes they all go to the water together, leave their shells on the shore, enter the water naked and spawn. Since they are naked they are vulnerable to a variety of predators, both terrestrial and marine, at this time. (Certain predatory fish congregate near soldier washes in August.) Once they are done "washing" the surviving adult crabs return to the land, find a shell from the many recently left by their companions and head out. There are always quite a few, well-used, unclaimed shells left in the morning - evidence of the ones that didn't make it. As for the eggs, they hatch and spend a time in the sea as free-swimming plankton. The hatchlings live in the ocean until their gills mature enough to be able to extract oxygen from air.

Once on land, the hermit crab begins to drink fresh water, but still requires salt water (sea salt) for functions like molting. After the last developmental molt, the modified gills lose the ability to process water and the crab can drown if trapped under water.

Captive C. clypeatus will not breed in an indoor environment, but have done so in an outdoor enclosure. None of the young lived past 10 days.

Spermiogenesis

The testes of the species Coenobita clypeatus contains germinal cells and non-germinative cells. The latter function in the manner of the vertebrate Sertoli cells in apparently providing nourishment, support and possibly hormones during spermiogenesis. Each Sertoli cell surrounds several germinal cells. The mitochondria, rough and smooth endoplasmic reticulum and Golgi apparatus show changes in structure when in contact with germinal cells in different stages of spermiogenesis. These changes are suggestive of active synthesis and metabolism of cellular products.

Cambarellus patzcuarensis

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Cambarellus patzcuarensis is a crayfish in the family Cambaridae with a body measuring 4–5 centimeters, including claws. The species is named after Lake Pátzcuaro, and is endemic to Mexico. Most specimen found in the wild are brown, sometimes with a gray or blue tint.

Cambarellus patzcuarensis var. "Orange" (Mexican dwarf crayfish, sometimes Mexican dwarf orange crayfish) is an orange-coloured mutation often held in aquariums, but this form is rarely found in the wild.

Australian red claw crayfish

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The Australian red claw crayfish, also called Queensland red claw or just redclaw, Cherax quadricarinatus, is an Australian freshwater crayfish. It is found in permanent freshwater streams, billabongs and lakes on the north coast of the Northern Territory and northeastern Queensland. Populations are also found in Papua New Guinea. Through translocation by humans, the range has spread down to southern Queensland and into the far north of West Australia. This tropical crustacean is very tolerant of environmental changes, and is primarily a detritivore.

Redclaw colour ranges from dark brown to blue-green body and adult males have a distinct red patch on the outer margin of the claws. They can reach up to 600 g. Redclaw are farmed commercially in Queensland and the Northern Territory, and are harvested at between 35 - 130 grams. Redclaw is a sought-after product with a delicate crustacean flavour. They are both non-aggressive in nature and highly fertile, and can therefore be bred in large numbers in captivity. Females, which are smaller than males, spawn approximately 300 olive green eggs which are fertilised from a spermatophore which the male has deposited at the base of her walking legs (periopods) during mating. Fertilised eggs are affixed to the females pleopods situated on the underside of the tail. Incubation takes approximately six weeks and the newly hatched juveniles rapidly become independent. The life cycle is simple and the animal reaches sexual maturity, and harvest size, somewhere between six to twelve months in optimal farmed conditions. Queensland Primary Industries & Fisheries provides information to prospective farmers.

Some varieties of the species may be kept as pets but if the exuvia is removed from the tank after sheding, the crayfish has an 80 percent chance of death. This is because the crayfish requires the calcium from its cast after sheding.

A subspecies known as rainbow lobster can be found off the coast of Thailand. It is sometimes exported to the United States and perhaps other countries to be served in Chinese restaurants. The meat is often sautéed and served with vegetables. The red claw crayfish is the only legal pet crayfish in the UK, other than the signal crayfish which can only be kept in certain parts of the UK.

Australian land hermit crab

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The Australian land hermit crab is one of two terrestrial hermit crab species native to Australia and is found in northern parts of Australia including northern Western Australia, Northern Territory and northern Queensland. The other terrestrial species is the strawberry land hermit crab (C. perlatus) which is reportedly restricted to the islands and coral cays of the Great Barrier Reef, north-eastern Australia. The Australian land hermit crab, like all hermit crabs, is a nocturnal, omnivorous crustacean. They thrive in tropical areas near water.

Shell preference

The preferred seashells of C. variabilis include Babylonia, Nerita, Phasianella, Thais, Tonna and Turban seashells. They are also found to be fond of several varieties of land snail shells such as Aratan snail and rice snail. As hermit crabs grow, they must exchange their shell for a larger one. Since intact gastropod shells are not an unlimited resource, there is frequently strong competition for the available shells, with hermit crabs fighting over shells.

The availability of empty shells depends on the abundance of the gastropods and hermit crabs, but most importantly on the frequency of organisms that predate on gastropods but leave the shells intact [2]. A hermit crab with a shell which is too tight cannot grow as fast as hermit crabs with well-fitting shells, and is more likely to be eaten [3]. Although hermit crabs need to change shells regularly, they will not abandon their old shell unless they have a larger and newer one to change into and unless they feel safe.

Diet

The Australian land hermit crab needs three main components in their diet to stay healthy; salt, calcium and protein. In the wild, they eat leaves, fish, bark, grass, fallen fruit, dead animals and even animal excrement.

Moulting

The Australian land hermit crab grows at a very steady rate. Every 2–18 months, depending on their size, a hermit crab will become very inactive and sluggish. This means that they are preparing for a moult. The signs of moulting are fatigue, eating and drinking large amounts and constantly digging or hiding. An Australian land hermit crab will only moult if it feels safe, has eaten and drunk enough and if it is not disturbed.

The moulting process usually begins with the hermit crab sitting on its side and being very inactive. The hermit crab then proceeds to slowly pull off its old exoskeleton and regenerate any lost limbs. After a moult, a hermit crab will be a pinkish colour and look much smaller that it was before. They are very vulnerable at this time and may die if disturbed.

Pastimes

The Australian land hermit crab is often purchased for the popular sport of "Crab Racing" in Australian bars. As with their Caribbean relatives they are placed in the middle of a circle and raced to the outer edge. They are commonly held in backpacker bars.

Tarantula

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Tarantulas comprise a group of hairy and often very large spiders belonging mainly to the family Theraphosidae, of which approximately 900 species have been identified. Historically tarantulas were the bigger genera from the family Lycosidae (like Lycosa tarantula). The colonists of the Americas gave the name to the bigger spiders of the tropic-dwelling families Theraphosidae and Dipluridae (funnel-web tarantulas), and that usage has now supplanted the earlier European one.

Some genera of tarantula hunt prey primarily in trees; others hunt on or near the ground. All tarantulas can produce silk—while arboreal species will typically reside in a silken "tube tent", terrestrial species will line their burrows with silk to stabilize the burrow wall and facilitate climbing up and down. Tarantulas mainly eat insects and other arthropods, using ambush as their primary method of prey capture. The biggest tarantulas can kill animals as large as lizards, mice, and birds. Tarantulas are found in tropical and desert regions around the world. Most tarantulas are harmless to humans, and some species are popular in the exotic pet trade. Some species, while not known to have ever produced human fatalities, have venom that can produce extreme discomfort over a period of several days.

The name 'tarantula' comes from the town of Taranto in Southern Italy and was originally used for an unrelated species of European wolf spider. The name was borrowed to apply to the theraphosids when Europeans explored areas where these large spiders were common. In Africa, theraphosids are frequently referred to as "baboon spiders". Asian forms are known as "earth tigers" or "bird-eating spiders". Australians refer to their species as "barking spiders", "whistling spiders", or "bird-eating spiders". People in French-speaking areas may apply the general name "mygales" to theraphosid spiders.

Like all arthropods, the tarantula is an invertebrate that relies on an exoskeleton for muscular support. A tarantula’s body consists of two main parts, the prosoma or the cephalothorax (the former is most often used) and the abdomen or opisthosoma. The prosoma and opisthosoma are connected by the pedicle, or what is often called the pregenital somite. This waist-like connecting piece is actually part of the prosoma and allows the opisthosoma to move in a wide range of motion relative to the prosoma.

Depending on the species, the body length of tarantulas ranges from 2.5–10 cm (1–4 inches), with 8- to 30-cm (3- to 12-inch) leg spans (their size when including their legs). Leg span is determined by measuring from the tip of the back leg to the tip of the front leg on the opposite side. The largest species of tarantula can weigh over 85 gms(3 ounces).The largest of all, the Goliath Birdeater (Theraphosa blondi) from Venezuela and Brazil, has been reported to have a weight of 150 gms (5.3 ounces) and a leg-span of up to 12 inches (30 cm), males being the longer and females greater in girth.

T. apophysis (the Pinkfoot Goliath) was described 187 years after the Goliath Birdeater; therefore its characteristics are not as well attested.T. blondi is generally thought to be the heaviest tarantula, and T. apophysis to have the greatest leg span. Two other species, Lasiodora parahybana (the Brazilian Salmon Birdeater) and L. klugi, rival the size of the two Goliath spiders.

The majority of North American tarantulas are brown. Elsewhere have been found species colored cobalt blue (Haplopelma lividum), black with white stripes (Aphonopelma seemanni), yellow leg markings (Eupalaestrus campestratus), metallic blue legs with vibrant orange abdomen and greenbottle blue (Chromatopelma cyaneopubescens). Their natural habitats include savanna, grasslands such as the pampas, rainforests, deserts, scrubland, mountains, and cloud forests. They are generally divided into terrestrial types that frequently make burrows and arboreal types that build tented shelters well off the ground.

Tarantulas are becoming increasingly popular as pets and are readily available in captivity. Most tarantulas are not strongly venomous to humans but their bite can be fatal to those with allergic reactions.

Etymology

The word tarantula has been applied to several very different kinds of spider. The spider originally bearing that name is one of the wolf spiders, Lycosa tarantula, found in the region surrounding the southern Italian town of Taranto. Compared to new-world tarantulas, wolf spiders are not particularly large or hairy.

Tarantism

The bite of L. tarantula was once believed to cause a fatal condition called tarantism, whose cure was believed to involve wild dancing of a kind that has come to be identified with the tarantella. However, modern research has shown that the bite of L. tarantula is not dangerous to human beings. There appears to have existed a different species of spider in the fields around Taranto responsible for fairly severe bites. The likely candidate (and the only spider found in the area which is dangerous to man) is the malmignatte or Mediterranean black widow. This spider, which belongs in the genus Latrodectus, is a close relative of the black widow and redback spiders, and has a bite which is medically significant. However, the Lycosa tarantulas, being larger and more fearsome-looking, tended to be unjustly credited with any severe bites.

New-world and other divergent usages

When theraphosids were encountered in the Americas, they were named "tarantulas", causing usage of the term to shift to the tropical spiders. Nevertheless, these spiders belong to the suborder Mygalomorphae, and are not closely related to wolf spiders.

The name "tarantula" is also mistakenly applied to other large-bodied spiders, including the purseweb spiders or atypical tarantulas, the funnel-webs (Dipluridae and Hexathelidae), and the "dwarf tarantulas". These spiders are related to tarantulas (all being mygalomorphs), but are classified in different families. Huntsman spiders of the family Sparassidae have also been termed "tarantulas" because of their large size. In fact, they are not related, belonging to the suborder Araneomorphae.

Appendages

The eight legs, the two chelicerae with their fangs, and the pedipalps are attached to the prosoma. The chelicerae are two double segment appendages that are located just below the eyes and directly forward of the mouth. The chelicerae contain the venom glands that vent through the fangs. The fangs are hollow extensions of the chelicerae that inject venom into prey or animals that the tarantula bites in defense, and they are also used to masticate. These fangs are articulated so that they can extend downward and outward in preparation to bite or can fold back toward the chelicerae as a pocket knife blade folds back into its handle. The chelicerae of a tarantula completely contain the venom glands and the muscles that surround them, and can cause the venom to be forcefully injected into prey.

The pedipalpi are two six-segment appendages connected to the thorax near the mouth and protruding on either side of both chelicerae. In most species of tarantula, the pedipalpi contain sharp jagged plates used to cut and crush food often called the coxae or maxillae. As with other spiders, the terminal portion of the pedipalpi of males function as part of its reproductive system. Male spiders spin a silken platform (sperm web) on the ground onto which they release semen from glands in their opistoma. Then they insert their pedipalps into the semen, absorb the semen into the pedipalps, and later insert the pedipalps (one at a time) into the reproductive organ of the female, which is located in her abdomen. The terminal segments of the pedipalps of male tarantulas are moderately larger in circumference than those of a female tarantula. Male tarantulas have special spinnerets surrounding the genital opening. Silk for the sperm web of the tarantula is exuded from these special spinnerets.

A tarantula has four pairs of legs and two additional pairs of appendages. Each leg has seven segments which, from the prosoma out, are: coxa, trochanter, femur, patella, tibia, tarsus and pretarsus, and claw. Two or three retractable claws are at the end of each leg. These claws are used to grip surfaces for climbing. Also on the end of each leg, surrounding the claws, is a group of hairs. These hairs, called the scopula, help the tarantula to grip better when climbing surfaces like glass. The fifth pair are the pedipalps which aid in feeling, gripping prey, and mating in the case of a mature male. The sixth pair of appendages are the chelicerae and their attached fangs. When walking, a tarantula's first and third leg on one side move at the same time as the second and fourth legs on the other side of his body. The muscles in a tarantula's legs cause the legs to bend at the joints, but to extend a leg, the tarantula increases the pressure of blood entering the leg.

Tarantulas, like almost all other spiders, have their primary spinnerets at the end of the opisthosoma. Unlike the typical spiders that on average have six, tarantulas have two or four spinnerets. Spinnerets are flexible tubelike structures from which the spider exudes its silk. The tip of each spinneret is called the spinning field. Each spinning field is covered by as many as one hundred spinning tubes through which silk is exuded. This silk hardens on contact with the air to become a threadlike substance.

Digestive system

The tarantula's mouth is located under its chelicerae on the lower front part of its prosoma. The mouth is a short straw-shaped opening that can only suck, meaning that anything taken into it must be in liquid form. Prey with large amounts of solid parts, such as mice, must be crushed and ground up or predigested, which is accomplished by coating the prey with digestive juices that are secreted from openings in the chelicerae.

The tarantula's digestive organ (stomach) is a tube that runs the length of its body. In the prosoma, this tube is wider and forms the sucking stomach. When the sucking stomach's powerful muscles contract, the stomach is increased in cross-section, creating a strong sucking action that permits the tarantula to suck its liquefied prey up through the mouth and into the intestines. Once the liquefied food enters the intestines, it is broken down into particles small enough to pass through the intestine walls into the hemolymph (blood stream) where it is distributed throughout the body. After feeding, the leftovers are formed into a small ball by the tarantula and thrown away. In a terrarium, they often put them into the same corner. As these balls are perfect hosts for moulds and parasites, they must be removed regularly.

Nervous system

A tarantula's central nervous system (brain) is located in the bottom of the inner prosoma. A tarantula perceives its surroundings primarily via sensory organs called setae (hairs or spines). Although a tarantula has eyes, touch is its keenest sense, and in hunting it primarily depends on vibrations given off by the movements of its prey. A tarantula's setae are very sensitive organs and are used to sense chemical signatures, vibrations, wind direction, and possibly even sound. Tarantulas are also very responsive to the presence of certain chemicals such as pheromones.

The eyes are located above the chelicerae on the forward part of the prosoma. They are small and usually set in two rows of four. Most tarantulas are not able to see much more than light, darkness, and motion. Arboreal tarantulas generally have better vision compared with terrestrial tarantulas.

Respiratory system

In all types of tarantula there are two sets of book lungs (breathing organs). The first pair of book lungs is located in a cavity inside the lower front part of the abdomen near where the abdomen connects to the cephalothorax and the second pair slightly farther back on the abdomen. Air enters the cavity through a tiny slit on each side of and near the front of the abdomen. Each lung consists of 15 or more thin sheets of folded tissue arranged like the pages of a book. These sheets of tissue are supplied by blood vessels. As air enters each lung, oxygen is taken into the blood stream through the blood vessels in the lungs. Needed moisture may also be absorbed from humid air by these organs.

Circulatory system

A tarantula’s blood is unique; an oxygen-transporting protein is present (the copper-based hemocyanin) but not enclosed in blood cells such as the erythrocytes of mammals. A tarantula’s blood is not true blood but rather a liquid called haemolymph, or hemolymph. There are at least four types of hemocytes, or hemolymph cells. The tarantula’s heart is a long slender tube that is located along the top of the opisthosoma. The heart is neurogenic as opposed to myogenic, so nerve cells instead of muscle cells initiate and coordinate the heart. The heart pumps hemolymph to all parts of the body through open passages often referred to as sinuses, and not through a circular system of blood vessels. If the exoskeleton is breached, loss of hemolymph will kill the tarantula unless the wound is small enough that the hemolymph can dry and close the wound.

Predators

Regardless of their fearsome reputation, tarantulas are themselves an object of predation, the most specialized of these predators are large members of the wasp family Pompilidae. In the Americas, these insects are termed "tarantula hawks", being parasitoids of tarantulas. The largest tarantula hawks, such as those in the genus Pepsis, will track, attack and kill large tarantulas. They use olfaction to find the lair of a tarantula. The wasp must deliver a sting to the underside of the spider's cephalothorax, exploiting the thin membrane between the basal leg segments. This paralyses the spider and the wasp then drags it back into its burrow before depositing an egg on the prey's abdomen. The wasp then seals the spider in its burrow and flies off to search for more hosts. The wasp larva hatches and feeds on the spider's non-essential parts and, as it approaches pupation, it consumes the remainder.

Defense

Besides the normal "hairs" covering the body, some tarantulas also have a dense covering of irritating hairs called urticating hairs, on the opisthosoma, that they sometimes use as protection against enemies. These hairs are present on new-world species but not on specimens from the Old World.

Urticating hairs are usually kicked off the abdomen by the tarantula, but it is noteworthy that some may simply rub the abdomen against the target, such is so with the Avicularia genera. These fine hairs are barbed and designed to irritate. They can be lethal to small animals such as rodents. Some people are extremely sensitive to these hairs, and develop serious itching and rashes at the site. Exposure of the eyes and breathing system to urticating hairs should be strictly avoided. Species with urticating hairs can kick these hairs off: they are flicked into the air at a target using their back pairs of legs. Tarantulas also use these hairs for other purposes such as to mark territory or to line their shelters (the latter such practice may discourage flies from feeding on the spiderlings). Urticating hairs do not grow back, but are replaced with each moult. The intensity, amount, and flotation of the hairs depends on the species of tarantula. Many owners of Goliath Birdeaters (T. Blondi) claim that theraphosids have the worst urticating hairs.

To predators and other kinds of enemies, these hairs can range from being lethal to simply being a deterrent. With humans, they can cause irritation to eyes, nose, and skin, and more dangerously, the lungs and airways, if inhaled. The symptoms range from species to species, from person to person, from a burning itch to a minor rash. In some cases, tarantula hairs have caused permanent damage to human eyes.

Some setae are used to stridulate, which makes a hissing sound. These hairs are usually found on the chelicerae. Stridulation seems to be more common in old-world species.

Bites and Urticating Hairs

Despite their often threatening appearance and reputation, none of the tarantulas are known to have a bite which is deadly to humans. In general, the effects of the bites of all kinds of tarantula are not well known. While the bites of many species are known to be no worse than a wasp sting, accounts of bites by some species are reported to be very painful. Because other proteins are included when a toxin is injected, some individuals may suffer severe symptoms due to an allergic reaction rather than to the venom.

New-world tarantulas (those found in North and South America) are equipped with urticating hairs on their abdomen, and will almost always throw these barbed hairs as a first line of defense. These hairs will irritate sensitive areas of the body and especially seem to target curious animals who may sniff these hairs into the mucous membranes of the nose. Some species have more effective urticating hairs than others. The Goliath Birdeater is one species known for its particularly irritating urticating hairs. Urticating hairs can penetrate the cornea so eye protection should be worn when handling such tarantulas.

Old-world tarantulas (from Europe and Asia) have no urticating hairs and are more likely to attack when disturbed. Old-world tarantulas often have more potent, medically significant venom. Before biting, tarantulas may signal their intention to attack by rearing up into a "threat posture", which may involve raising their prosoma and lifting their front legs into the air, spreading and extending their fangs, and (in certain species) making a loud hissing noise by stridulating. Their next step, short of biting, may be to slap down on the intruder with their raised front legs. If that response fails to deter the attacker they may next turn away and flick urticating hairs toward the pursuing predator. Their next response may be to leave the scene entirely, but, especially if there is no line of retreat, their final response may also be to whirl suddenly and bite.

There are dangerous spider species which are related to tarantulas and frequently confused with them. A popular urban legend maintains that deadly varieties of tarantula exist somewhere in South America. This claim is often made without identifying a particular spider although the "banana tarantula" is sometimes named. A likely candidate for the true identity of this spider is the dangerous Brazilian wandering spider Phoneutria nigriventer, of the family Ctenidae, as it is sometimes found hiding in clusters of bananas and is one of several spiders called the "banana spider." It is not a tarantula but it is fairly large (4–5 inches long), somewhat hairy, and highly venomous to humans. Another dangerous type of spider that has been confused with tarantulas is the Australasian funnel-web spider. The best known of these is the Sydney funnel-web spider Atrax robustus, a spider that is aggressive, highly venomous, and (prior to the development of antivenin in the 1980s) was responsible for numerous deaths in Australia. These spiders are members of the same suborder as tarantulas. Some Australians use the slang term 'triantelope' for large, hairy and harmless members of the Huntsman spider family which are often found on interior household walls.

Medical implications

While no fatalities have been attributed to tarantula bites, sometimes spider bites are regarded as the probable source of infections. Medical advice regarding prophylaxis may be helpful in that regard. In addition, there is considerable anecdotal evidence indicating that the venoms of some old-world species can produce symptoms so severe that medical treatment would be appropriate. Medical intervention is also regarded as appropriate when symptoms such as breathing difficulty or chest pain develop, since these conditions may indicate an anaphylactic reaction. As with bee stings, allergic reactions to protein fractions may be many times more dangerous than the direct toxic effects of the venom.

Sexual dimorphism

Some tarantula species exhibit pronounced sexual dimorphism. Males tend to be smaller (especially their abdomens, which can appear quite narrow) and may be quite dull when compared to their female counterparts, as in the species Haplopelma lividum. Mature male tarantulas also may have tibial hooks on their front legs, which are used to restrain the female's fangs during copulation.

A juvenile male's sex can be determined by looking at a cast exuvium for exiandrous fusillae or spermathecae. Ventral sexing is less reliable, but, if done correctly, it can be relatively reliable. Males have much shorter lifespans than females because they die relatively soon after maturing. Few live long enough for a post-ultimate moult. It is unlikely that it happens much in natural habitats because they are vulnerable to predation, but it has happened in captivity if rarely. Most males do not live through this moult as they tend to get their emboli, mature male sexual organs on pedipalps, stuck in the moult. Most tarantula fanciers regard females as more desirable as pets due to their much longer lifespan. Wild caught tarantulas are often mature males because they wander out in the open and are more likely to be caught, while females remain hidden in their burrows.

Life cycle

Like other spiders, tarantulas have to shed their exoskeleton periodically in order to grow, a process called moulting. A young tarantula may do this several times a year as a part of the maturation process, while full grown specimens will only moult once a year or less, or sooner in order to replace lost limbs or lost urticating hairs.

The Moulting Process

A tarantula is obviously going to moult (or "shed", as some call it) when the exoskeleton takes on a darker shade. If a tarantula previously used its urticating hairs, the bald patch will turn from a peach color to deep blue.

Tarantulas may live for years—most species taking 2 to 5 years to reach adulthood, but some species may take up to 10 years to reach full maturity. Upon reaching adulthood, males typically have but a 1 to 1.5 year period left to live and will immediately go in search of a female with which to mate. Male tarantulas rarely moult again once they reach adulthood. The oldest spider, according to Guinness World Records, lived to be 49 years old.

Females will continue to moult after reaching maturity. Female specimens have been known to reach 30 to 40 years of age, and have survived on water alone for up to 2 years. Grammostola rosea spiders are renowned for going for long periods without eating.

Reproduction

As with other spiders, the mechanics of intercourse are quite different from those of mammals. Once a male spider reaches maturity and becomes motivated to mate, it will weave a web mat on a flat surface. The spider will then rub its abdomen on the surface of this mat and in so doing release a quantity of semen. It may then insert its pedipalps (short leg-like appendages between the chelicerae and front legs) into the pool of semen. The pedipalps absorb the semen and keep it viable until a mate can be found. When a male spider detects the presence of a female, the two exchange signals to establish that they are of the same species. These signals may also lull the female into a receptive state. If the female is receptive then the male approaches her and inserts his pedipalps into an opening in the lower surface of her abdomen, called the Opithosoma. After the semen has been transferred to the receptive female's body, the male will swiftly leave the scene before the female recovers her appetite. Although females may show some aggression after mating, the male rarely becomes a meal.

Females deposit 50 to 2000 eggs, depending on the species, in a silken egg sac and guard it for 6 to 7 weeks. During this time, the female will stay very close to the egg sac and become more aggressive. Within most species, the female turns the egg sac often, which is called brooding. This keeps the eggs from deforming due to sitting too long. The young spiderlings remain in the nest for some time after hatching where they live off the remains of their yolk sac before dispersing.

Scorpion

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Scorpions are predatory arthropod animals of the order Scorpiones within the class Arachnida. There are about 2,000 species of scorpions, found widely distributed south of about 49° N, except New Zealand and Antarctica. The northernmost part of the world where scorpions live in the wild is Sheerness on the Isle of Sheppey in the UK, where a small colony of Euscorpius flavicaudis has been resident since the 1860s.

Reproduction

Most scorpions reproduce sexually, and most species have male and female individuals. However, some species, such as Hottentotta hottentotta, Hottentotta caboverdensis, Liocheles australasiae, Tityus columbianus, Tityus metuendus, Tityus serrulatus, Tityus stigmurus, Tityus trivittatus, and Tityus urugayensis, reproduce through parthenogenesis, a process in which unfertilized eggs develop into living embryos. Parthenogenic reproduction starts following the scorpion's final moult to maturity and continues thereafter.

Sexual reproduction is accomplished by the transfer of a spermatophore from the male to the female; scorpions possess a complex courtship and mating ritual to effect this transfer. Mating starts with the male and female locating and identifying each other using a mixture of pheromones and vibrational communication.. Once they have satisfied each other that they are of opposite sex and of the correct species, mating can commence.

The courtship starts with the male grasping the female’s pedipalps with his own; the pair then perform a "dance" called the "promenade à deux". In reality this is the male leading the female around searching for a suitable place to deposit his spermatophore. The courtship ritual can involve several other behaviours such as juddering and a cheliceral kiss, in which the male's chelicerae—clawlike mouthparts—grasp the female's in a smaller more intimate version of the male's grasping the female's pedipalps and in some cases injecting a small amount of his venom into her pedipalp or on the edge of her cephalothorax, probably as a means of pacifying the female.

When the male has identified a suitable location, he deposits the spermatophore and then guides the female over it. This allows the spermatophore to enter her genital opercula, which triggers release of the sperm, thus fertilizing the female. The mating process can take from 1 to 25+ hours and depends on the ability of the male to find a suitable place to deposit his spermatophore. If mating goes on for too long, the female may eventually lose interest, breaking off the process.

Once the mating is complete, the male and female will separate. The male will generally retreat quickly, most likely to avoid being cannibalized by the female, although sexual cannibalism is infrequent with scorpions.

Birth and development

Unlike the majority of arachnid species, scorpions are viviparous. The young are born one by one, and the brood is carried about on its mother's back until the young have undergone at least one molt. Before the first molt, scorplings cannot survive naturally without the mother, since they depend on her for protection and to regulate their moisture levels. Especially in species which display more advanced sociability (e.g. Pandinus spp.), the young/mother association can continue for an extended period of time. The size of the litter depends on the species and environmental factors, and can range from two to over a hundred scorplings. The average litter however, consists of around 8 scorplings.

The young generally resemble their parents. Growth is accomplished by periodic shedding of the exoskeleton (ecdysis). A scorpion's developmental progress is measured in instars (how many moults it has undergone). Scorpions typically require between five and seven moults to reach maturity. Moulting is effected by means of a split in the old exoskeleton which takes place just below the edge of the carapace (at the front of the prosoma). The scorpion then emerges from this split; the pedipalps and legs are first removed from the old exoskeleton, followed eventually by the metasoma. When it emerges, the scorpion’s new exoskeleton is soft, making the scorpion highly vulnerable to attack. The scorpion must constantly stretch while the new exoskeleton hardens to ensure that it can move when the hardening is complete. The process of hardening is called sclerotization. The new exoskeleton does not fluoresce; as sclerotization occurs, the fluorescence gradually returns.

Life and habits

Scorpions have quite variable lifespans and the actual lifespan of most species is not known. The age range appears to be approximately 4–25 years (25 years being the maximum reported life span in the species Hadrurus arizonensis). Lifespan of Hadogenes species in the wild is estimated at 25–30 years.

Scorpions prefer to live in areas where the temperatures range from 20 °C to 37 °C (68 °F to 99 °F), but may survive from freezing temperatures to the desert heat. Scorpions of the genus Scorpiops living in high Asian mountains, bothriurid scorpions from Patagonia and small Euscorpius scorpions from middle Europe can all survive winter temperatures of about −25 °C. In Repetek (Turkmenistan) there live seven species of scorpions (of which Pectinibuthus birulai is endemic) in temperatures which vary from 49,9 °C to -31 °C.

They are nocturnal and fossorial, finding shelter during the day in the relative cool of underground holes or undersides of rocks and coming out at night to hunt and feed. Scorpions exhibit photophobic behavior, primarily to evade detection by their predators such as birds, centipedes, lizards, mice, possums, and rats.

Scorpions are opportunistic predators of small arthropods and insects. They use their chelae (pincers) to catch the prey initially. Depending on the toxicity of their venom and size of their claws, they will then either crush the prey or inject it with neurotoxic venom. This will kill or paralyze the prey so the scorpion can eat it. Scorpions have a relatively unique style of eating using chelicerae, small claw-like structures that protrude from the mouth that are unique to the Chelicerata among arthropods. The chelicerae, which are very sharp, are used to pull small amounts of food off the prey item for digestion. Scorpions can only digest food in a liquid form; any solid matter (fur, exoskeleton, etc) is disposed of by the scorpion.

Venom

All known scorpion species possess venom and use it primarily to kill or paralyze their prey so that it can be eaten; in general it is fast-acting, allowing for effective prey capture. It is also used as a defense against predators. The venom is a mixture of compounds (neurotoxins, enzyme inhibitors, etc.) each not only causing a different effect, but possibly also targeting a specific animal. Each compound is made and stored in a pair of glandular sacs, and is released in a quantity regulated by the scorpion itself. Of the over thousand known species of scorpion, only a few have venom that is dangerous to humans.

Ultraviolet light

Scorpions are also known to glow when exposed to certain wavelengths of ultraviolet light such as that produced by a blacklight, due to the presence of fluorescent chemicals in the cuticle. The principal fluorescent component is now known to be beta-Carboline. A hand-held UV lamp has long been a standard tool for nocturnal field surveys of these animals. However, a glow will only be produced in adult specimens as the substances in the skin required to produce the glow are not found in adolescents.

Pinktoe tarantula

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The pinktoe tarantula, Avicularia avicularia, is a species of tarantula native to South America, Costa Rica to Brazil, and the southern Caribbean. This species is sometimes called the Guyana pinktoe, Common pinktoe or South American pinktoe since they are frequently harvested from those areas, and has pink feet pads.

The mature pinktoe tarantula has a dark-colored body and pinkish feet, in keeping with its name. Juvenile specimens, however, have pinkish bodies and dark-colored feet. Pinktoe tarantulas undergo a reversal in their coloration as they approach adulthood at 4-5 years.

These types of tarantulas are very docile, albeit nervous and jumpy, and are frequently kept as pets. Although all tarantulas are prone to cannibalism, pinktoes are more tolerant of one another and can be stored in the same vivarium, if it is large enough. Being arboreal species, they require a relatively tall habitat with plenty of climbing space. They require a lot of moisture, along with ample ventilation to prevent molds from developing.

Ornithoctoninae

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Ornithoctoninae, also known as earth tigers, are a sub-family of old-world tarantulas, which were first erected in 1895 by Reginald Innes Pocock on basis of the genotype Ornithoctonus andersoni described in 1892 from former Burma, now Myanmar.

The Ornithoctoninae is a theraphosid sub-family, which are widely distributed in Asia from Myanmar to South China in the north and as far as to Halmahera in the Indonesian archipelago in the south, and in all the ranges in between. Most species in the sub-family live fossorially in burrows, though there are several species which are living arboreally in trees. They are known as defensive spiders; when disturbed they will quickly retreat into their burrows or dig themselves into the soil. When neither is a possility, they will assume a defensive posture. When provoked, they will strike the aggressor repeatedly with the anterior legs; if the aggressor does not retreat these spiders has been known to bite. Though not deadly, the effects of the venom can be very unpleasant including pain, swelling and arthritis like stiffness in the joints of the extremity affected.

The theraphosid subfamily Ornithoctoninae is defined by the following combination of characters. Presence of retrolateral scopula of filiform setae on the cheliceral base. a small row of larger filiform paddle setae retrolaterally ventro-basally in connection to the retrolateral cheliceral scopula. Arrangement of stridulatory spines prolaterally on maxilla. The character of retrolateral scopula of filiform setae on the cheliceral base is shared by the African subfamily Harpactirinae, but the Ornithoctoninae can be distinguished from the Harpactirinae by the geographic distribution range and the presence of the other characters mentioned, which are lacking in the Harpactirinae.

Care of Ornithoctoninae kept as pets

Specimens from the genera Haplopelma, Cyriopagopus, and Ornithoctonus are frequently kept as pets. The most commonly kept species are: Haplopelma albostriatum, H. hainanum, H. lividum, H. longipes, H. minax, H. schmidti, Ornithoctonus aureotibialis and Cyriopagopus schioedtei. More species are kept and new species enters the hobby every now and then, but most of this material need to be proberly identified or described.

Haplopelma and Ornithoctonus are burrow-dwellers. A high soil level (at least 15 cm, or 6") is necessary for them to be able to successfully dig burrows. This behavior is described by von Wirth and Huber in the "Haplopelma-tanks" (2002, 2004), which also recommends frequently watering the cage. Alternatively, one can create a "fauna box" by filling up a cage (as high as possible, up to a few centimeters below the top) with potting soil, one can place (as high as possible) a "fauna box", which one fills up with potting soil, coconut compost, or a peat moss mixture. However this method is less advantageous than the method recommended in the Haplopelma Spezialbecken. Temperatures of 23°-25°C are sufficient.

One should accommodate Cyriopagopus in a terrarium for tree-dwellers, but one should also include a high soil level, since the animals do like to dig into the soil, especially as juveniles.

Lasiodora parahybana

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The Brazilian salmon pink is a popular species of tarantula kept as pets in the tarantula keeping hobby today. Originating from Brazil (hence the common name), this spider typically grows to a leg span of 20 cm (8 in), although occasionally exceptional specimens can reach leg spans of 25 cm (10 in). Large females can weigh upwards of 100 grams. They are not recommended for beginners, as they are fast, large, and will possibly kick off urticating hairs if annoyed. Not quick to bite, however, this species is considered somewhat 'handleable' in the hobby, but its fangs (in adults and sub-adults) are capable of medically significant mechanical damage. This tarantula is one of the largest in the world, often cited as the second or third largest (after the T. blondi). In the wild the Brazilian salmon pink tarantula has even been known to prey on the deadly fer-de-lance pit viper snake.

Care

These arachnids can be kept quite easily in a terrarium that measures at least four times its leg span in length but not too high as a fall can kill this tarantula due to its size. The tarantula loves a humid environment, thriving at relative humidities of between 65–80%. However the keeper should be aware that mold can form at very high humudities, so good ventilation (especially cross ventilation) is crucial. The terrarium should be furnished with a deep substrate (peat moss or vermiculite are the most popular in the hobby today) and a water dish. Isopods kept live in the substrate help with mold as they've been known to eat it, as well as feeder remains. They should be kept at temperatures of around 25 °C (75 to 85° F). Schultz (1998) states "The largest giant tarantulas (e.g. Lasiodors parahybana, L klugi and Theraphosa blondi) require an unexpected amount of food compared to other more conventional tarantulas. One enthusiast feeds his collection three subadult mice a week; these tarantulas are definitely not for the rank amateur, the faint of heart, or a person of limited income." The staple diet in captivity is the (Acheta domestica, Orthopotera Gryllidae) or domestic house crickets; an adult Lasiodora parahybana can consume several in one sitting, this can be supplemented with pinkie mice once or twice a month. Most collectors, however, do not recommend supplementing with mice. Many collectors prefer to feed roaches to their tarantulas, especially those as large as the L. parahybana. They are easily more filling than a cricket.

These tarantulas are ideal show specimens, as they web little, hide rarely, and will often sit out in the open for you to see. Younger L. parahybana's may regularly utilize a burrow, but will become more bold with size.

Avicularia

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Avicularia is a genus of the family Theraphosidae containing various species of tarantulas. The genus is native to tropical South America. Each specie in the genus has very distinguishable pink feet pads.

One of the most notable features of the Avicularia species is its odd method of defense. When threatened, their first choice is to jump or run away as quickly as possible - occasionally, though, they will launch a jet of excrement at the perceived threat. Adults are capable of good accuracy and a range of 0.5-1 m (2 or 3 feet).

There is also a belief that they may be the reason behind rumors of "flying spiders" in the rainforests they are native to, as they are quite adept at jumping. Their legs, however, prevent them from gaining much height in making a jump.

Avicularia avicularia are among the tarantulas most commonly kept as pets.