Hermit crab (Latin scientific name: Paguridae), also known as "white house", "dry house", mainly uses the shell as a host, and the maximum diameter of the largest snail in the hermit can reach more than 15 cm. Its shape is between shrimp and crab, mostly inhabited by snail shells. The body is long, divided into head, thorax and abdomen. The cephalothorax has cephalothorax, but does not cover the last thoracic segment. The anterior part of the cephalothorax is narrower, more calcified, the posterior part is wider, or completely membranous, with a pronounced cervical groove. The abdomen is long, curly or straight, a few species wide and short, and mostly asymmetrical.
Hermit crabs are mostly found on the coast of the Yellow Sea and the southern seas, and are easy to find in the rock crevices of the beach and the sea, and sometimes this omnivore known as the "scavenger" can also be seen in other places such as bamboo knots, coconut shells, corals, sponges, etc. Hermit crabs are not listed in the list of wild animals under national key protection and belong to general protected animals.
Hermit crab is a general term for the general family of hermit crabs and the general family of land-based crabs. Its shape is between shrimp and crab, mostly inhabited by snail shells. The body is long, divided into head, thorax and abdomen. The cephalothorax has cephalothorax, but does not cover the last thoracic segment. The anterior part of the cephalothorax is narrower, more calcified, the posterior part is wider, or completely membranous, with a pronounced cervical groove. The abdomen is long, curly or straight, a few species wide and short, and mostly asymmetrical.
The general family of hermit crabs includes hermit crabs, quasi-hermit crabs, stone crabs, etc., common such as large hermit crabs (square wrist hermit crabs), with a large body shape, a large claw length of more than 10 cm, many thorny protrusions on the surface and edges of the two claws, and spines on the foot. The general family of terrestrial hermit crabs includes the living hermit crab family, the terrestrial hermit crab family, the chelated hermit crab family, etc., and the common ones such as the Ai's live hermit crab and the lower toothed fine claw hermit crab. Nearly 1,000 species are known worldwide and about 100 in China. Most of them are warm water species, and there are a few cold water species in the Yellow Sea.
Except for a few species, the hermit crab generally has an asymmetrical body left and right, a soft abdomen, and can be curled in a snail shell. The caudal segment is also often asymmetrical. There are ocular scales at the base of the stalk. The 1st antennae stalk is often folded, and the base of the 2nd antennae stalk has a spine. The basal segments of the 3rd pair of jaws are either adjacent or adjacent, or separated from the left and right. A pair of claws, with strong claws, for food against enemies. The 1st and 2nd pairs of step feet are long, and the 3rd and 4th pairs of step feet for crawling are generally very small, with mattresses, which can support the inner wall of the snail shell and stabilize the body. The male reproductive foramen opens on the basal segment of the 4th pair of stepper feet. The female reproductive foramen is on the basal segment of the 2nd pair of step feet. The abdominal limbs are degenerate, and the sides are often asymmetrical, often present only on one side. Females are more developed and are used for egg holding. The left side of the cauldal limbs and caudal segments are often more developed than the right side, with rough bedding. This specialized tail fan is used to hook the inside of the shell so that it is not pulled out. When the body gradually grows, it can be replaced at any time with a larger empty shell. Species living in the intertidal zone are often active, while species in the deep sea are more sluggish. Feed on small or dead animals. Terrestrial species are omnivorous. Males are often larger than females. In order to compete for females, the two males often fight each other. Usually crawling on the seashore or in shallow water, if in case of danger, it is retracted into the shell of the snail and plugged with the snail mouth with a chelated foot. A small number of burrowing or parasitic species within the straight tubes of horned shells and worms, the abdomen is not curved. Hermit crabs often coexist with other animals, such as the large anemones on the large claws of the Live-forehead Hermit Crab, and some hermit crabs, which inhabit sponges or coelenterates, because these two types of animals can continue to grow, so the hermit crabs do not have to change to a new home often. The lower-toothed hermit crab has a row of teeth on the inner margin under the long segment of the claw foot, and the posterior end of the tooth is extraordinarily large and can rub and make sounds.
The hermit crab lives in the armor of its predators, but because of this armor, it must run around on its back, even making its right claw larger than its left claw, or its left claw larger than its right claw.
Hermit crabs often inhabit the shells of dead mollusks to protect their soft abdomen, hence the name.
There are more than 500 species of hermit crabs in the world, most of which live in water and a few on land. Some hermit crabs no longer live in the carapace, but have developed a hard shell similar to crabs, also called hard shell hermit crabs, the famous coconut crab is this category. Kamchatka stone crab (Alaskan king crab) is a close relative of the hermit crab and was once classified by biologists into the hermit crab family (now in the stone crab family).
Common hermit crabs can be divided into three main categories: live-fronted hermit crabs, hermit crabs, and land-based hermit crabs.
Because the hermit crab is very heterogeneous, is an omnivorous animal, they are known as the scavengers of the sea, from algae, food scraps to parasites, for family fish lovers, putting one or two hermit crabs in the aquarium will play the role of cleaners.
The lifespan of hermit crabs is generally 2 to 5 years, but in a good breeding environment, it can often live to 20 to 30 years, and the longest recorded life is 70 years.
The house of the hermit crab has conch shells, shells, snail shells, and even uses bottle caps as a home due to the harsh ecological environment. When the hermit crab was born, the body was relatively soft and easy to be eaten, and when it grew up, it had to find a house suitable for itself, so it attacked the conch and killed and shredded the conch. Then drill in, hook the top of the shell with the tail, support the inner wall of the shell with several short legs, and crawl outside the shell with the long legs, and guard the shell mouth with a large claw. In this way, it moved into a new home that is environmentally friendly and sturdy.
Wrinkle parasitism
Wrinkled Hermit Crab (Tawny Hermit Crab)
Scientific name: Coenobita rugosus
Origin: East Coast of Africa to South Pacific countries
Habitat: Coastal area Body length: 6 to 11 cm in total length
Temperature: 23 to 28 degrees Celsius
Wrinkled hermit crab is also one of Taiwan's three native hermit crabs, and their body color changes are more than those of concave-footed hermit crabs. There are almost all colors between white and black, and the most important feature is that their claws and legs appear to be relatively slender. There is little difference in size between the two claws. The wrinkled hermit crab can be regarded as the most interactive with the owner among the pet hermit crabs, so it is also the most popular with the owner. They are not only lively and bold, but also like to climb, very receptive to the owner's pick-up, but also like to change the shell, overall, seems to show a relatively high IQ. Therefore, the fun in breeding will be relatively high.
The artificial environment and food of the wrinkled hermit crab are the same as those of the concave-footed hermit crab, and the saplings or culture soil can also be used as a substrate, and fresh water and seawater must be supplied at any time. In particular, when they first buy it home, they should immediately provide seawater for them to drink. They are also suitable for group or polyculture, and since they like to climb, they can be arranged with some rocks or sunken wood to make them climb high.
Wrinkled hermit crabs are also typical nocturnal crabs, usually eating at night, so the feeding time is more suitable for the evening. They are probably also the most adaptable of Taiwan's three land-based crab species. Those interested in raising hermit crabs may wish to be more handy with wrinkled hermit crabs.
Strawberry parasitism
Strawberry Hermit Crab
Scientific name: Coenobita perlatus
Origin: Indian Ocean to South Pacific countries Habitat: Coastal zone
Body length: 5 to 10 cm in total length
Suitable temperature: 21 to 27 degrees Celsius
The distribution area of strawberry hermit crab is very extensive, from Madagascar in the Indian Ocean through Indonesia to Samoa in the southeast pacific ocean of Australia. This vast area also happens to cover the tropical seas between the Tropic of Cancer. Taiwan is also in this region, so it is also distributed. They are the most beautiful and easily distinguished species among the hermit crabs, because they are bright red throughout and scattered with white spots, which are almost the embodiment of strawberries, so they are called strawberry hermit crabs abroad. Taiwan's hermit crab doctor Shi Xide called it a pearl hermit crab.
Although terrestrial hermit crabs can live on land, their umbilical cord with the sea is not severed, because part of their life cycle must still be completed in the sea, that is, from spawning to hatching to larval stage. So for the rest of their lives, strawberry hermit crabs will not and cannot live far from the coast. When they are reared, they must also be provided with fresh water and seawater for drinking.
The artificial environment is most suitable for obtaining convenient coral fine sand or broken coral, using dry bark to build a dwelling, and then putting a shallow plate of fresh water and a shallow plate of sea water to complete the basic layout. Seawater can be prepared by itself with artificial seawater that are sold in seawater fish shops. send
The lungs of the crab need to have the appropriate humidity to complete the respiration, so the water is absolutely indispensable, especially the sea water is the key to raising the hermit crab. Do not keep the land hermit crab in the water, they will drown. The short-palmed hermit crab does not like too high humidity, so the substrate will be more suitable for their habits to keep dry. In addition to this, the daily care of strawberry hermit crabs is very easy.
They are scavengers, which means that they can accept almost anything they can eat. Any feed, fruits and vegetables, rice, dead fish and shrimp they do not refuse. However, strawberry hermit crabs differ from ordinary hermit crabs in that they need to be supplemented with carotene frequently to maintain a bright body color. Otherwise, the red color will gradually fade. The best source of carotene is shrimp or red tropical fish for brightening feed. In addition, they also have a social habit, so individuals who are raised alone will not be as adaptable as multiple breeders.
Strawberry hermit crabs need to be peeled like regular crabs, but also need to change their shells. When the hermit crab peels, it usually digs the bottom sand to bury itself, at which time the bottom sand needs to be kept moist, and the hermit takes about ten days to harden after peeling. Injured and severed limbs are usually regenerated after peeling. As for shell change, this is a unique pleasure of raising hermit crabs, which must constantly change their shells as they grow. Therefore, several shells of different sizes should be prepared for their replacement. Hermit crab shops also sell a variety of rare shells. These shells are usually polished and very dazzling. Many owners also use their imagination to paint shells and give their hermit crabs a unique and personalized shell. Due to the unique breeding pattern of hermit crabs, it is unlikely that hermit crabs will reproduce in artificial environments. The largest female and male hermit crabs are the male reproductive foramen opening in the waist segment of the 5th pair of pectoral feet, while the female reproductive foramen is located in the 4th pair of pectoral feet. During mating, the male will store the seminal vesicles in the female, and the female will fertilize the egg by the way when laying the egg. About 10,000 to 50,000 eggs are laid at a time. Females use their swimming limbs to hold the fertilized eggs in their abdomen for a period of time. When the eggs have developed to a certain extent, the female will bring the eggs to the shore to discharge, let the eggs enter the sea with the waves to hatch into plankton, and after many peeling in the sea, they will evolve into juvenile crabs before coming ashore, and after finding shells to live, they will settle on land.
In general, strawberry hermit crabs can survive for 25 to 30 years, but they can usually only survive for 2 to 4 years in artificial environments, which should have a lot to do with being out of the ocean. If they could arrange a half-land, half-sea intertidal environment, they should be able to live better and longer. The proportion of people who have raised hermit crabs in Taiwan should be very high, but there should not be many people who really know how to raise or really raise them as pets, perhaps in today's professional breeding of hermit crabs, we may once again explore the fun of raising hermit crabs.
Concave paradals
Concave Hermit Crab
Scientific name: Coenobita cavipes
Origin: East Coast of Africa to the Ryukyu Islands
Habitat: Coastal area
The most eye-catching feature of the concave-footed hermit crab is its pair of bright red tentacles. Their body color varies from dark red to taupe or multicolored, but their tentacles are usually red. Their eye stalks have a slight curvature, which is not found in other hermit crabs. The personality of the concave-footed hermit crab is more shy or more inclined to the typical nocturnal type, so it often hides in the substrate and comes out at night to forage for food activities.
The artificial environment and food of the concave-footed hermit crab are the same as those of the short-palmed hermit crab, which can be immersed in seawater for several hours. They are also suitable for group or polyculture, but a small number of individuals can also be aggressive, but usually do not cause serious consequences.
Concave-footed hermit crabs are also native to Taiwan and are also common in the southern coast, usually scattered in groups along the coast. When picking up shells, you may wish to take a closer look, maybe there is a concave-footed hermit crab living inside.
Purple land parasite
Scientific name: Coenobita purpureus
Origin: A variety unique to Japan. Ogasawara Island, south of Kagoshima.
Body color: purple blue, purple, blue
Features and Description:
The eyes are quadrangular in shape. In addition to the body color, it is very similar to the gray and white land hermit crab. The joints of the crayon and thorax are distinctly yellowish brown. The left claw is dorsal with diagonal rows of particles that make a "squeaking" sound. The purple hermit crab is milky white when it is young, but as it grows, the purple part gradually increases, and finally the body becomes completely purple.
Short palm parasitism
Short-palmed hermit crab Indonesian Hermit Crab
Scientific name: Coenobita brevimanus
Origin: Indian Ocean to South Pacific countries
The distribution area of the short-palmed hermit crab is similar to that of the general hermit crab, which is distributed in a large area from the Indian Ocean to the South Pacific. Taiwan also has a large ethnic group. Their biggest feature is that they are more drought tolerant than other hermit crabs after coconut crabs. They also have an extra-large purple left claw, round eyes and dark tentacles that make them easily distinguishable from other Taiwanese hermit crabs.
The artificial environment of raising short-palmed hermit crabs is similar to that of strawberry hermit crabs, which is most suitable for obtaining convenient coral sand or broken corals, using dry bark to build a dwelling, and then putting a shallow plate of fresh water and a shallow plate of seawater to complete the most basic arrangement. Other features can be added to your personal preference. Of course, it is more ideal to prepare a few empty shells of different sizes for them to replace at any time.
They are also scavengers and are acceptable to almost anything they can eat. Any feed, fruits and vegetables, rice, dead fish and shrimp they do not refuse. In addition, they have a mild personality, so there is usually no fight with other species. Their peeling habits, like those of other hermit crabs, burrow into the substrate and peel, reappear after peeling.
Short-palmed hermit crabs are also common in Taiwan's seashore, but most of them are juveniles, sub-adults or adults are rare, mainly imported from Southeast Asia. However, because the difficulty of raising hermit crabs is not high, as long as you know the correct method, it is not difficult to raise the larvae. At least it's easier than raising reptiles.
Worldwide distribution. It lives on sandy bottoms, muddy bottoms, and occasionally on land or in trees. The abdominal appendages of the female crab are used to carry the eggs until they hatch. Immediately after hatching, the larvae enter the water to look for empty shells. When the body grows up, it leaves the original snail shell to find and move into a larger new home.
Some hermit crabs live in plant stem tubes. Semi-terrestrial tropical species of the land-dwelling crab genus live in addition to snail shells, but also live in bamboo knots, cracked coconut shells, and other items. The hermit crab of the door claw inhabits the deep waters of the Indian Ocean and lives in bamboo knots. Xylopargus is found in water 180 to 360 m (600 to 1,200 ft) deep in the Western Indian Ocean, inhabiting cylindrical hollow wood. Other species inhabit corals or sponges, and some live in symbiosis with other animals. Pagurus bernhardus (i.e. Eupagurus bernhardus) is common off the coasts of Europe and North America, with a bright red color, often carrying one or more sea anemones on its shell. Native to the islands of the South Pacific, robber crab is terrestrial and has abandoned its habit of inhabiting snail shells. The large hermit crab (Pagurus pollicaris) is found in the waters of the Atlantic coast of North America, light reddish-brown, and about 10 to 12 cm (4 to 5 inches) long. P. longicarpus is small, found in the waters off the Atlantic coast of the United States, cylindrical.
The areas with the highest density of hermit crabs are often in the upper intertidal zone of coral reefs, turning over the stones in the waterlogged places, and often finding a lot of bare-palmed hard-shell hermit crabs and fine claws, which move quickly and will quickly escape and hide. In addition, because the ecological conditions in the tide pond are relatively mild, they will not be affected by waves, and they can retain water at low tide, and most hermit crabs will gather on the edge of the tide pool or under the stones in the pool. The tidal pools of the climactic line of Orchid Island Coral Reef are highly temperatured and have large salinity changes due to sun exposure, but there are Syss hard-shell hermit crabs and light-palmed hard-shell hermit crabs that inhabit them.
In terms of vertical distribution, the land hermit crab only inhabits the coastal wetland, the fine chelated hermit crab only inhabits the climatic zone, the hard-shell hermit crab is distributed in the entire intertidal zone and the shallow subtidal zone, and the true hermit crab is widely distributed in the intertidal zone, the shallow sub-tidal zone and the shallow sea. Take the hard-shelled hermit crab that has been carefully studied in Taiwan as an example, this genus of hermit crab is widely distributed in the intertidal and subtidal zones of the tropics and subtropics, especially coral reefs and reef platforms, which are the dominant species on most hard coasts and are also easy to find on the coast of Taiwan. The range of habitat of different hard-shell hermit crabs is not the same, some species appear only in the intertidal zone, such as bare-palmed hard-shelled hermit crabs and Systoche hermit crabs; some often appear in the shallow subtidal zone, such as The Gay's hard-shell hermit crab, guam hard-shell hermit crab, and the tiny hard-shell hermit crab; however, some species are found in both the intertidal zone and the subtidal zone, such as the recessive hard-shelled hermit crab; and the other rare species are found in the seafloor below the shallow sub-tidal zone, such as the linear-footed hard-shell hermit crab and the graceful hard-shell hermit crab. Most of the hard-shell hermit crabs are not active, often hanging upside down under the rocks or staying on steep slopes, in the shallow sub-tidal zone, they mostly gather at the top of coral bushes, when the hard-shell hermit crabs feel interference, they will immediately shrink into the shell, making themselves fall into the bushes, making it difficult for the enemy to catch it, which is a very effective behavior of avoiding the enemy.
Hermit crabs are mainly found in the Yellow Sea and the coastal edges of the southern and East China Seas, generally living in rock crevices on the beach and on the seashore. The hermit crab uses the snail shell as a host, usually crawls in the negative shell, and when frightened, it will immediately shrink its body into the snail shell. As the crab body grows, the hermit crab will look for new shells to change its shell.
There are dozens of known hermit crab species, and the more common species along the coast of China are the square-wristed hermit crab and the ctenophoric hermit crab. The square-wrist hermit crab is slightly larger than the ctenophore hermit crab, and the maximum diameter of the hermit snail can reach more than 15 cm.
The shell carried by the hermit crab is a good hard substrate of benthic organisms, and there are many organisms living in symbiosis with it. Among them, stingrays (especially anemones and hydra) are larger and have been studied more thoroughly.
The symbiotic relationship between most hermit crabs and spiny animals is not absolute, nor is the relationship between them one-to-one, and most of the relationships are mutually beneficial and symbiotic. The spiny cells of the anemone provide some degree of protection for the hermit crab, while the anemone obtains a hard substrate that inhabits the shell and debris when the hermit crab forages. The hydra also provides some degree of protection for the hermit crab and prevents other large and harmful epitaphs from forming colonies on the shell; in addition to obtaining debris, the hydra can also avoid submergation by the substrate, and even promote the sexual reproduction of the hydra when the hermit crabs gather.
When establishing a symbiotic relationship between hermit crabs and anemones, both parties may take the initiative, depending on the species. Both have a fixed behavioral process to complete this relationship, or they can artificially trigger this behavioral process. Hermit crabs place anemones in place on their shells to gain a balance of center of gravity or effective defense against enemies. In the absence of predators, hermit crabs gradually lose their ability to acquire sea anemones, but this behavior resumes immediately when there are predators. The dominant individual can take away the resource of the anemone from the disadvantaged.