Recent developments on the morphology of the brachyuran foregut ossicles and gastric teeth

Abstract

The complexity of the brachyuran foregut, in particular the foregut ossicles and gastric teeth, were investigated and documented in 66 brachyuran taxa employing a new staining method. The brachyuran groundpattern is proposed to consist of 41 ossicles. Most of the ossicles show a very conservative pattern with only a few variations. A previous classification scheme proposed by Nauck (1880) with the grouping of the recent brachyuran crabs in Heterodontea and Cyclodontea is not supported by this study. The study also shows that the Heterodontea and Cyclodontea are not monophyletic.