Revision of the Elusive Harvestmen Genus Discocyrtulus Roewer, 1927 (Opiliones: Laniatores: Gonyleptidae): Investigating the Presumed Northeastern Brazilian Discocyrtus-Like Relatives

Abstract

A maximum parsimony analysis based on morphological characters (23 taxa; 98 characters; 1951 scorings) was conducted to test the monophyly of Discocyrtulus Roewer, 1927, and to assess its phylogenetic relationships within Gonyleptidae. The results recover the species currently assigned to Discocyrtulus as phylogenetically distant from Pachylinae sensu stricto and nested instead within Discocyrtus sensu stricto+, forming a clade together with Discocyrtus moraesianus Mello-Leitão, 1923. Accordingly, Discocyrtulus is removed from Pachylinae Sørensen, 1884, and left without subfamilial assignment. As a result, Discocyrtulus now comprises Discocyrtulus crenulatus (Roewer, 1913) comb. nov., Discocyrtulus marginalis Roewer, 1929, and Discocyrtulus moraesianus (Mello-Leitão, 1923) comb. nov. Based on the examination of type material, the following species-level synonymies are proposed: Heteropucrolia nigrosulcata Mello-Leitão, 1932 syn. nov., and Discocyrtulus bresslaui Roewer, 1927 syn. nov. (type species of Discocyrtulus) of Discocyrtus crenulatus Roewer, 1913; Discocyrtus melanacanthus Mello-Leitão, 1932 syn. nov. of Discocyrtulus marginalis Roewer, 1929; and Discocyrtus coxalis Roewer, 1929 syn. nov. of Discocyrtus moraesianus Mello-Leitão, 1923. The genus Heteropucrolia Mello-Leitão, 1932 is removed from the synonymy of Discocyrtus and transferred to Discocyrtulus. We also designate herein lectotypes of D. bresslaui and D. marginalis. Issues concerning the type localities of Discocyrtulus marginalis and Heteropucrolia nigrosulcata are also addressed, challenging previous records of Discocyrtulus from north-eastern Brazil and clarifying historical misinterpretations of species distributions.