Amid the fallen leaves: Intense collecting in the Northern Atlantic Forest reveals new minute harvestmen species (Opiliones: Stygnidae) within the Area of Endemism of Pernambuco

Abstract

Stygnids represent one of the most diverse harvestman families, with many endemic species in the Area of Endemism of Pernambuco, a pattern increasingly evident by intensified sampling in the region over the years. The area is also recognised for hosting a group of understudied minute leaf-litter dwellers stygnids, represented by the following monotypic genera: Gaibulus Roewer, 1943; Iguarassua Roewer, 1943; and Kaapora Pinto-da-Rocha, 1997. In this study, we describe a male specimen of Iguarassua schubarti Roewer, 1943; describe two new Iguarassua species, Iguarassua brejoensis sp. nov. and Iguarassua villarreali sp. nov.; examine the type series of Kaapora minutissimus (Roewer, 1943); and discuss the overall relationships of the leaf-litter Stygnidae in the Northern Atlantic Forest. We propose K. minutissimus syn. nov. to be a junior synonym of I. schubarti, thereby synonymising Kaapora syn. nov. under Iguarassua, and identify key diagnostic characters related to pedipalp setae curvature and penis morphology, indicating that all current Atlantic Forest leaf-litter stygnids, including Gaibulus, are possibly monophyletic, likely placed in Stygninae and are most closely related to Pickeliana Mello-Leitão, 1932.