User:Cbodnar20/Episesarma versicolor

copied from Episesarma versicolor

Description
'The genus Episesarma'' is comprised of some of the largest sesarmid crabs. E. versicolor is distinguished by its white tipped violet chela (claw).''' Males grow up to a maximum length of 5 cm. The carapace is square-shaped and relatively flat, colored brown to brownish grey. The first gonopod of male E. versicolor has a narrower, shorter tip compared to other members of the genus. The dorsal portion of the dactylus possess 65-80 densely packed projections called tubercles These bony spine-like structures are more pronounced in males and, as seen in other crab species with tubercles, seem to be stridulatory organs for generating sound.

Habitat
This species is well distributed in mangrove regions, inhabiting burrows at tree bases or sometimes mounds created by Thalassina lobsters. '''Comparatively, mangroves have a high degree of biodiversity and provide a niche specific to the crab that decreases interspecific competition for food and other resources. E. versicolor favors the forest more than the Thalassina mound system in comparison to other species in the Episesarma genus.'''

Feeding
Episesarma versicolor are omnivorous, but feed primarily on calyx and leaves of water plants, mangroves, and mangrove associates. 'At Segara Anakan Lagoon, Java, Indonesia, E. versicolor'' feed on various food sources including detritus, bark, leaves, and on roots, algae and animal matter to a lesser extent. Their diet adapts to the environment, which helps them survive when food sources are scarce or changing. When food is abundant, such as during a feeding experiment, they prefer leaves with a high amount of nitrogen compounds.''' They have been observed cutting leaf litter and bringing some fragments back to their burrows. To remove leaves from trees, they tear off a section of the leaf with their claws and feed on those small sections they tear off. Leaves with previous damage from other herbivorous organisms are targeted by the crabs for feeding, utilizing previous holes to tear off sections more easily.

Migration
'E. versicolor'' burrow when the tide is low in day time, unless heavy rainfall forces them out of the burrows. When the tide is high, the larger crabs climb up trees, while smaller crabs stay burrowed. They can climb as high as 6m up.  The crabs do not feed while they stay up on the trees, which indicates that they migrate to avoid predators during high tide. Predators such as fish and hard-shelled crabs can enter the larger burrows of E. versicolor, which forces larger individuals to climb up trees. However, while on the trees, E.versicolor are vulnerable to terrestrial predators and avoid detection by staying motionless on the tree trunks. '''

Commercial fisheries
E. versicolor is an important part of commercial fisheries in Southeast Asia. '''They are harvested by hand and often pickled in vinegar and/or salt solutions to be eaten with rice or deep fried. Due to their popularity in Thailand, they are being overfished. 18,000 tons of sesarmid crabs like E. versicolor are harvested from mangrove habitats and are consumed by Thai people. 12,000 tons of crab harvested annually from the Thai mangroves cannot keep up with domestic demand. Hence, Thailand imports at least 6000 tons of sesarmid crabs from the neighboring countries of Myanmar and Cambodia.'''