The spider genus Bistriopelma Kaderka, 2015 is endemic to Peru and includes three species known to date: Bistriopelma lamasi Kaderka, 2015, B. matuskai Kaderka, 2015 and B. titicaca Kaderka, 2017. The present contribution diagnoses, describes and illustrates two new species of Bistriopelma from Peru: B. peyoi sp. nov. and B. kiwicha sp. nov., both based on male and female. The male of B. peyoi sp. nov. is provided with a remarkable thoracic horn, and the species is the first horned tarantula for this genus. An updated distribution map for all known species is presented.

A new species of Linothele Karsch, 1879 from southern Peru is described and illustrated, L. mubii sp. nov. The new species can be distinguished from other species of the genus by scopulation in combination with the morphology of copulatory organs.

The tarantula genus Tmesiphantes Simon, 1892 includes 20 valid species distributed in Argentina and Brazil. These spiders are distinguished from other Theraphosinae genera by the presence of an incrassate femur III, more evident in males, urticating hair types III and IV on the abdominal dorsum, few cuspules on the labium (0 to 30), maxillae with a maximum of 200 cuspules and sternum rounded. From recent examination of material from Peru, we discovered specimens that share all the morphological characters of Tmesiphantes, but did not fi t with any known species. In the present study T. intiyaykuy sp. nov. is diagnosed, described, and illustrated. This new species resembles T. caymmii in the circular patch with stiff setae on midventral abdomen but can be distinguished by the shape of the palpal bulb and spermathecae. Also, we performed a phylogenetic analysis using morphological characters to infer the taxonomic placement of the new species. The analysis included 26 terminal species and 36 characters. Representatives of Tmesiphantes formed a monophyletic group and T. intiyaykuy sp. nov. is close related with T. caymmii. A dichotomous identifi cation key and a geographic distribution map were constructed for recognized species of Tmesiphantes.

Reportamos un nuevo registro en la distribución geográfica de Chaco tucumana en la provincia de Salta, norte de Argentina. Es la localidad más al norte conocida para la especie. Además, presentamos datos sobre la historia natural de la especie y mapas de distribución incluyendo comentarios de las provincias biogeográficas y ecorregiones involucradas.