Limb morphology of the carnivorous anomopods Anchistropus emarginatus Sars, 1862 and Pseudochydorus globosus (Baird, 1843) (Crustacea: Branchiopoda: Anomopoda)

Abstract

We studied the morphology of two ‘flesh-eating’ Chydoridae Anchistropus emarginatus Sars, 1862 and Pseudochydorus globosus (Baird, 1830), using populations from Belgium, with particular attention to the structure of the trunk limbs. Both genera belong in subfamily Chydorinae, and both have morphological adaptations with implications for the interpretation of limb morphology in the subfamily. Anchistropus has a large number of specific characters, many of which directly relate to the animal’s habit of feeding on Hydra. In Pseudochydorus globosus, specializations are less numerous. A redescription of both species is offered, with an aim at allowing future comparisons with populations outside the Palaearctic, where cryptic species are expected to occur.