A taxonomic revision of the Liphistius birmanicus-group (Araneae: Liphistiidae) with the description of five new species

Most of the species of the Liphistius birmanicus-group are revised on the basis of genital morphology and an identification key to all species is given. Twelve species are recognized: seven previously known, five new. Liphistius metopiae Schwendinger, sp. nov. from northern Thailand, and L. tung Schwendinger, sp. nov., L. ferox Schwendinger & Huber, sp. nov., L. cupreus Schwendinger & Huber, sp. nov. and L. platnicki Schwendinger & Huber, sp. nov. from eastern Myanmar are described from both sexes. New males and females of L. birmanicus Thorell, 1897, L. pinlaung Aung et al., 2019 and L. pyinoolwin Xu et al., 2021 from the type localities are illustrated. A new locality each for L. birmanicus and for L. pinlaung is reported; additional taxonomic characters of the type specimens of L. lahu Schwendinger, 1998 are shown. Illustrations of intraspecific variation among the new specimens and information on their biology are given. The presumed relationships within the birmanicus-group and between this group and other species groups in Liphistius are discussed. Lateral pockets in the uterus externus, a previously overlooked structure of unknown function in the female genitalia of Liphistius species, are illustrated.