A new species of Tanymastigites Brtek, 1972 (Anostraca: Tanymastigidae) from Libya, with a revised key to the genus and new crustacean records (Branchiopoda, Copepoda, Ostracoda) from Algeria

Abstract The fairy shrimp Tanymastigites ajjeri n. sp. is described from a temporary water body, or guelta, in the Sahara Desert near the Tadrart mountains, east of Tassili n’Ajjer National Park, Libya. Males are readily separated from congeners by the morphology of the frontal appendages, which have an undivided lateral ramus and ≥ 0.4× the length of the medial ramus, and by the second antennae, in which the medial lamellar process bears a spatulate distal lobe. The new species is most similar to congeners T. perrieri (Daday, 1910) and T. mzabica (Gauthier, 1928), and it represents the sixth described species in this genus. We provide an updated key to the genus and comments on its diagnosis and definition, particularly concerning the descriptive terminology of the second antennae. In addition, we provide a list of new records of species of Branchiopoda, Copepoda, and Ostracoda from Tassili n’Ajjer National Park.