A revision of the Thyropygus allevatus group. Part 1: the T. opinatus subgroup (Diplopoda: Spirostreptida: Harpagophoridae) Author Pimvichai, Piyatida Author Enghoff, Henrik Author Panha, Somsak text Zootaxa 2009 2016 17 50 journal article 10.5281/zenodo.185971 1db39382-b4f0-46fa-ae08-dd5e57e0e26b 1175-5326 185971 Genus Thyropygus Pocock, 1894 Thyropygus Pocock, 1894 : 380 Thyropisthus Attems, 1942 : 86 , synonymized by Hoffman (1975) Cornugonus Demange, 1961 : 177 , new synonym See Hoffman (1975) and Jeekel (2006) for extensive synonymies. Diagnosis No proper, up-to-date diagnosis of Thyropygus is available. The genus was placed in the subfamily Harpagophorinae by Demange (1961) and in the tribe Thyropygini by Hoffman (1975) . The circumscription of Thyropygini was later modified by Jeekel (2006) . The following diagnosis of Thyropygus has been extracted from these authors: ozopores starting on body ring 6 body rings not strongly wrinkled dorsally stigmatic grooves very long, reaching at least the middle of the leg prefemora postfemur and tibia of male walking legs with ventral soft pads gonopod sternum present, triangular gonopod telopodite with a femoral and mostly also a tibial spine, but without numerous spines along all its length prostatic groove terminating apically on a solenomere or prostatic lobe (apical palette of telopodite) in a narrowly expanded area set with a series of long, slender, stiffened, usually pigmented spines (“blepharochaetae” of Hoffman, 1975 ) apical palette voluminous, more or less expanded, forming a somewhat gutter-like structure Further revisionary work on harpagophorids is likely to lead to modification of this diagnosis. Hoffman (1975) grouped the species of Thyropygus into four species groups: the allevatus , aterrimus, luxuriosus, and erythropleurus groups. The last group contains the type species of Thyropygus , T. erythropleurus Pocock, 1894 (Sumatra) and might alternatively be termed “ Thyropygus s.s. ” The present paper is the first in a planned series focused on the T. allevatus group.