Monday, 13. July 2009, 22:35
Text: Monika Rademacher
Photos: Oliver Mengedoht
Translation: Ulli Bauer
Scientific name: Geosesarma sp.
Trivial name: Blue Vampire Crab
Systematics: Domain: Eucaryota, kingdom: Animalia, subkingdom: Metazoa (multiple-celled animals), Eumetazoa (true tissue), grade: Bilateria, branch: Protostomia, infrakingdom: Ecdysozoa (molting animals), phylum: Arthropoda (jointed-leg invertebrates), subphylum: Crustacea, class: Malacostraca (higher crustaceans), superorder: Eucarida, order: Decapoda (ten-legged crayfish), suborder: Pleocyemata, infraorder: Reptantia, section: Brachyura (true crabs), superfamily: Grapsoidea, family: Sesarmidae (mangrove crabs), genus: Geosesarma, species: Geosesarma sp. (not yet identified)
Origin/Distribution: unknown (South-East Asia)
[attachment=8220]
more pix: http://www.panzerwelten.de/v/Geosesarma/Geosesarma_blue
Description: dark, brown carapace, back/lower half of the back carapace blue, claws wine red to intensive purple (towards the body) to brown (towards the end), eyes whiteish to greenish.
[attachment=8221]
This is why we gave them the name of "Blue Vampire Crabs" or Geosesarma sp. "blue"…
[attachment=8222]
The blue lower half of the carapace, whereas the rest looks very similar to "Vampire Crabs".
Sex differences: Typical for crabs, the males have a narrow apron, the females have a wider apron nearly covering the entire abdomen. Moreover, females of this species seem to be of a more subdued color.
[attachment=8223]
Male: claws display an intensive wine red to purple color (depending on the light).
[attachment=8224]
More subdued, with brownish instead of purple hues: the females.
Size: carapace is up to at least 2 cm wide.
Life span: unknown (assumed to be two to four years)
Water temperature: tropical (around 20 to 28 °C, more active from 24 °C upwards)
Tank size/stock: from 25 cm length on for one pair, however, keeping them in a small group and in a tank from 60 cm upwards seems preferrable, if possible more females than males. However, a stock with an equal number of both sexes also seems to be apt given that the tank is well-structured.
Tank set-up: Aquaterrarium with a larger land part; well-structured with various levels to climb, hideouts and substrate allowing to burrow; plants (also weeping forms), moss.
[attachment=8225]
[attachment=8226]
Examples of suitable aquaterrariums
Food: as far as we know they're primarily carnivorous
• Frozen foods: blackworms, bloodworms, glassworms, cyclops, brine shrimp, clam meat
• Live foods: earthworms (however, best cut in parts in order to prevent them from digging into the ground - under water, too! -, drowning and thus rotting in the ground undiscovered), gammarus, shrimp, snails
• Fish: deep-frozen smelts and the like, tuna fish, sardines, herring etc., either fresh or from a can {in their own juice, not in oil}
• Other: they also accept fruit and small granulated as well as flake food
[attachment=8227]
The young crabs have an extremely good camouflage and are hard to spot.
Behavior: Relatively peaceful, their requirements when kept in a tank vary strongly: There are some of these crabs that remain exclusively on the land parts, others, however, stay mainly in the water or on seats with direct water contact. It is striking that they seem location-bound, the crabs look for a convenient spot in the aquaterrarium and only move within a very limited range around this place from then on.
They only seldomly look for food actively, these crabs mostly accept food directly in their reach or food they literally stumble upon on their limited-range strolls.
[attachment=8228]
Unfortunately, this crab hasn't survived; many of its limbs were missing, and it had a hole in its carapace, above the gills.
Reproduction: Specialized reproduction in fresh water with fully developed young crabs instead of larvae. The females carry relatively large eggs (> 1mm). Young crabs obviously need a real water part for successful development! When berried, the females mainly stay in their burrows and caves.
Socialization: Shrimp, snails (smaller specimens might be eaten).
[attachment=8229]
A young crab, aged only a few hours or days.
Additional information:
• Three of the four males of this species at first delivered to us did not survive (two had obviously suffered during transport, the third one was severely hurt {hole in the gill area of the carapace}). Almost all the crabs of the three pairs we got after that have survived for over a year, only then one of the males didn't get through a molt. This leads us to believe that they are relatively stable.
• In the meantime, we have seven of these crabs sitting in a 45-cm aquaterrarium (4.3). They live together relatively peacefully, are sedate and hardly ever change their place. They prefer animal food. The females almost always sit in their burrows in the land parts, the males are often in the water or on seats allowing them water contact at least with their feet.
The first crab offspring we had from them disappeared entirely within only a few days. We still don't know whether they were eaten by the adults or if the surroundings back then didn't suit them. Then we kept these crabs in a terrarium with a very small water area. After putting them into a tank with a significantly larger water part, a new litter of young crabs seem to develop well.
• They are absolutely incompatible with Geosesarma sp. "vampire" (Vampire Crabs). The "Vampires" will soon eat the "Blues" - partially and entirely!
Photos: Oliver Mengedoht
Translation: Ulli Bauer
Scientific name: Geosesarma sp.
Trivial name: Blue Vampire Crab
Systematics: Domain: Eucaryota, kingdom: Animalia, subkingdom: Metazoa (multiple-celled animals), Eumetazoa (true tissue), grade: Bilateria, branch: Protostomia, infrakingdom: Ecdysozoa (molting animals), phylum: Arthropoda (jointed-leg invertebrates), subphylum: Crustacea, class: Malacostraca (higher crustaceans), superorder: Eucarida, order: Decapoda (ten-legged crayfish), suborder: Pleocyemata, infraorder: Reptantia, section: Brachyura (true crabs), superfamily: Grapsoidea, family: Sesarmidae (mangrove crabs), genus: Geosesarma, species: Geosesarma sp. (not yet identified)
Origin/Distribution: unknown (South-East Asia)
[attachment=8220]
more pix: http://www.panzerwelten.de/v/Geosesarma/Geosesarma_blue
Description: dark, brown carapace, back/lower half of the back carapace blue, claws wine red to intensive purple (towards the body) to brown (towards the end), eyes whiteish to greenish.
[attachment=8221]
This is why we gave them the name of "Blue Vampire Crabs" or Geosesarma sp. "blue"…
[attachment=8222]
The blue lower half of the carapace, whereas the rest looks very similar to "Vampire Crabs".
Sex differences: Typical for crabs, the males have a narrow apron, the females have a wider apron nearly covering the entire abdomen. Moreover, females of this species seem to be of a more subdued color.
[attachment=8223]
Male: claws display an intensive wine red to purple color (depending on the light).
[attachment=8224]
More subdued, with brownish instead of purple hues: the females.
Size: carapace is up to at least 2 cm wide.
Life span: unknown (assumed to be two to four years)
Water temperature: tropical (around 20 to 28 °C, more active from 24 °C upwards)
Tank size/stock: from 25 cm length on for one pair, however, keeping them in a small group and in a tank from 60 cm upwards seems preferrable, if possible more females than males. However, a stock with an equal number of both sexes also seems to be apt given that the tank is well-structured.
Tank set-up: Aquaterrarium with a larger land part; well-structured with various levels to climb, hideouts and substrate allowing to burrow; plants (also weeping forms), moss.
[attachment=8225]
[attachment=8226]
Examples of suitable aquaterrariums
Food: as far as we know they're primarily carnivorous
• Frozen foods: blackworms, bloodworms, glassworms, cyclops, brine shrimp, clam meat
• Live foods: earthworms (however, best cut in parts in order to prevent them from digging into the ground - under water, too! -, drowning and thus rotting in the ground undiscovered), gammarus, shrimp, snails
• Fish: deep-frozen smelts and the like, tuna fish, sardines, herring etc., either fresh or from a can {in their own juice, not in oil}
• Other: they also accept fruit and small granulated as well as flake food
[attachment=8227]
The young crabs have an extremely good camouflage and are hard to spot.
Behavior: Relatively peaceful, their requirements when kept in a tank vary strongly: There are some of these crabs that remain exclusively on the land parts, others, however, stay mainly in the water or on seats with direct water contact. It is striking that they seem location-bound, the crabs look for a convenient spot in the aquaterrarium and only move within a very limited range around this place from then on.
They only seldomly look for food actively, these crabs mostly accept food directly in their reach or food they literally stumble upon on their limited-range strolls.
[attachment=8228]
Unfortunately, this crab hasn't survived; many of its limbs were missing, and it had a hole in its carapace, above the gills.
Reproduction: Specialized reproduction in fresh water with fully developed young crabs instead of larvae. The females carry relatively large eggs (> 1mm). Young crabs obviously need a real water part for successful development! When berried, the females mainly stay in their burrows and caves.
Socialization: Shrimp, snails (smaller specimens might be eaten).
[attachment=8229]
A young crab, aged only a few hours or days.
Additional information:
• Three of the four males of this species at first delivered to us did not survive (two had obviously suffered during transport, the third one was severely hurt {hole in the gill area of the carapace}). Almost all the crabs of the three pairs we got after that have survived for over a year, only then one of the males didn't get through a molt. This leads us to believe that they are relatively stable.
• In the meantime, we have seven of these crabs sitting in a 45-cm aquaterrarium (4.3). They live together relatively peacefully, are sedate and hardly ever change their place. They prefer animal food. The females almost always sit in their burrows in the land parts, the males are often in the water or on seats allowing them water contact at least with their feet.
The first crab offspring we had from them disappeared entirely within only a few days. We still don't know whether they were eaten by the adults or if the surroundings back then didn't suit them. Then we kept these crabs in a terrarium with a very small water area. After putting them into a tank with a significantly larger water part, a new litter of young crabs seem to develop well.
• They are absolutely incompatible with Geosesarma sp. "vampire" (Vampire Crabs). The "Vampires" will soon eat the "Blues" - partially and entirely!