Developmental and other body abnormalities in the genus Lepidurus Leach, 1819 (Crustacea: Notostraca) from Serbia

The occurrence of morphological abnormalities and the emergence of body defects are well-known phenomena in crustaceans and other groups of arthropods. They usually originate from genetic factors and are attributable to aberrations during the moulting process, but they can also be of exogenous origin. The aims of this study were to present the external body changes that occurred in large branchiopod crustaceans of the genus Lepidurus Leach, 1819 (Notostraca) sampled in Serbia and discuss their possible etiology. The majority of variations were identified on the carapace and limbs, followed by ones on the abdominal part of the body, telson with caudal lamina, and cercopods. As for potential causes, the observed variations can be attributed both to genetic factors and to non-genetic ones such as predatory stress and possible environmental disturbance. Certain deviations from the mean phenotype point to irregular development (or an unpatterned moulting process) and to a possible disease. Some of the body transformations observed here influenced symmetry and functional morphology of the individuals, and may have ecological and ethological implications.