Revisiting the tarantula genus Neischnocolus Petrunkevitch, 1925 (Araneae, Theraphosidae): new insights on male palpal bulb morphology and description of three new species

Abstract. We reassess the palpal bulb morphology and taxonomy of Neischnocolus Petrunkevitch, 1925 based on the examination of several types of previously described species and the description of three new species (N. moraspungo Cisneros-Heredia, Peñaherrera-R., Guerrero-Campoverde, León-E., Gabriel & Sherwood sp. nov., N. samonellaacademy Peñaherrera-R., León-E., Guerrero-Campoverde, Gabriel, Sherwood & Cisneros-Heredia sp. nov., and N. tiputini Guerrero-Campoverde, Peñaherrera-R., León-E., Gabriel, Sherwood & Cisneros-Heredia sp. nov.) from Ecuador. A new keel structure is named and herein considered as a valid diagnostic feature for the genus, previously identified as a prolateral inferior keel. The rest of the keel identification of Neischnocolus is also relabelled in concordance with Bertani’s (2000) keel homology hypothesis. Amended diagnoses of almost all the species are provided, leaving only Neischnocolus obscurus (Ausserer, 1875) since the type material has not been located.