Arachnothelphusa cf. merarapensis from central Sarawak / Borneo – around 1600m ASL

We already knew from the crab genus Arachnothelphusa that they must have a direct development. This in-situ photo now clearly shows for the first time that this is the case. Usually crabs have a larval stage, the females release countless larvae into the sea and thus the larvae become zooplankton and pass through the larval stages in the ocean. Some crab species, such as Geosesarma and Arachnothelphusa, have developed a different reproduction strategy and the larval stage of the young animals is passed through within the egg. The fully developed juveniles hatch from the eggs and are carried around by the mother for a few more days.