Analysis of the Ilyocryptus spinifer-species group (Anomopoda, Branchiopoda), with description of a new species

We studied the morphology and variability of Ilyocryptus spinifer Herrick, 1882 from different parts of the world using optical microscopy and SEM, re -examining type material wherever possible. Morphometric analysis failed to reveal significant regional differences between populations. The following species names for members of Ilyocryptus spinifer group, I. halyi Brady, 1 886; I. longiremis Sars, 1888; I. immundus F. Mueller in Ihering, 1895; I. verrucosus Daday, 1905 and I. tetraspintus Berganim, 1939, are junior synon yms of I. spinifer. A new species from this group is described from Queensl and, Australia. Ilyocryptus timmsi n. sp. shows unique morphological charac ters in the armature of the lateral swimming setae of the antennal endopod, its apical segment and the postabdominal claws.