The first Hapalotremus Simon, 1903 (Araneae: Theraphosidae) from Argentina: description and natural history of Hapalotremus martinorum sp. nov. Author Cavallo, Patricio E. Universidad CAECE (Centro de Altos Estudios en Ciencias Exactas), Buenos Aires, Argentina; Author Ferretti, Nelson E. Centro de Estudios Parasitológicos y de Vectores CEPAVE (CCT- CONICET- La Plata) (UNLP), La Plata, Argentina text Journal of Natural History 2014 2014-06-30 49 15 873 887 journal article 21072 10.1080/00222933.2014.953226 70bc86d1-f7e8-48d1-bfb7-1ad323a24b36 1464-5262 4004661 Genus Hapalotremus Simon, 1903 Dolichothele Mello-Leitão, 1923 . Considered a junior synonym by Raven 1985: 152 . Goniodontium Mello-Leitão, 1923 . Considered a junior synonym by Raven 1985: 153 . Cyclothorax Mello-Leitão, 1923 , preoccupied. Replacement name Cyclothoracoides Strand, (1929) : 17. Considered a junior synonym by Raven 1985: 151 . Hemirrhagus Simon, 1903 (in part: H. major Chamberlin, 1916 ). Diagnosis Representatives of the genus can be distinguished from the remaining Theraphosinae by the presence of reddish or whitish setae (colour of live specimens) on dorsum abdomen, presence of Type III urticating hair, labium wider than long with reduced labial cuspules (from 5 to 7 in H. albipes and H. major ), with the exception of Hapalotremus martinorum sp. nov. with 28 labial cuspules in females. It is characterized by the tarsi fully scopulated and divided by rows of setae increasing in width from legs I to IV, with tarsus IV divided by five or six rows of setae. Males of Hapalotremus are also recognized by the following features: tibial apophysis present with two branches, the prolateral bearing a long stiff black thorn on inner side, slightly curved at tip and of similar size to the spur, the retrolateral with a long spine inserted on inner side at the middle of the spur, metatarsus of leg I noticeably curved at base, and male palpal bulb with embolus subcylindrical curved to the retrolateral side with conspicuous subapical keel. Females may be also recognized by the single spermathceal receptaculum.