A new genus of Pseudospirobolellidae (Diplopoda, Spirobolida) from limestone karst areas in Thailand, with descriptions of three new species Author Pimvichai, Piyatida https://orcid.org/0000-0001-9765-821X Department of Biology, Faculty of Science, Mahasarakham University, Maha Sarakham 44150, Thailand piyatida_pimvichai@yahoo.com Author Enghoff, Henrik https://orcid.org/0000-0002-2764-8750 Natural History Museum of Denmark, University of Copenhagen, Universitetsparken 15, DK- 2100 Copenhagen O, Denmark Author Panha, Somsak Animal Systematics Research Unit, Department of Biology, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand Author Backeljau, Thierry https://orcid.org/0000-0002-9057-9727 Royal Belgian Institute of Natural Sciences, Vautierstraat 29, B- 1000 Brussels, Belgium & Evolutionary Ecology Group, University of Antwerp, Universiteitsplein 1, B- 2610 Antwerp, Belgium text Zoosystematics and Evolution 2022 2022-08-19 98 2 313 326 http://dx.doi.org/10.3897/zse.98.90032 journal article http://dx.doi.org/10.3897/zse.98.90032 1860-0743-2-313 A757241549264A16810AF6D1F55F12BE D1F1582D2AD25C51B3736DA7086235FA Siliquobolellus prasankokae gen. et sp. nov. Figs 2 , 5 , 6 , 7 Material studied. Holotype . 1 male (CUMZ-D00148-1), Thailand , Lampang Province , Ngao District , Pha Thai ; 18°36'01.05"N , 99°54'01.00"E ; 350 m a.s.l. ; 28 July 2020 ; P. Pimvichai , P. Prasankok and S. Saratan leg. Paratypes . 6 females (CUMZ-D00148-2); same data as holotype . Etymology. The species honors Associate Professor Dr. Pongpun Prasankok, biologist and devoted millipede collector. Diagnosis. Differing from other species in the genus by having the posterior gonopod apically with a short, sharp protrusion; externally differing by having a row of rectangular dark brown spots middorsally on the body rings. Description. Adult male with 41 podous rings, 1 apodous ring. Length ~3 cm, diameter ~3 mm. Adult females with 40 or 41 podous rings, 1 apodous ring. Length ~3 cm, diameter 3.2-3.6 mm. Color of living animal: collum and telson beige; antenna and leg light brown; dorsal part of body rings yellowish brown, with a row of rectangular dark brown spots middorsally on the body rings; head and lateral part of body rings dark brown (Fig. 2I , 6C, D ). Anterior gonopods (Fig. 5A, B, D, E ) with high coxae, apically narrow, curving mesad, mesal margin sigmoid, posterior surface folding to cover more than half of telopodite, with strong ridge laterally. Telopodite with thick process, with strong ridge distomesally (Fig. 5B , arrow). Posterior gonopods (Fig. 5C, F-J ) simple, rounded, with short, smooth coxal part (pcx); telopodital part (pt) twice the length of the pcx, lateral margin folding mesad, forming a deep concavity, the inner lateral margin expanded into a rounded lamella, apically forming a canopy (Fig. 5I , arrow), apically with a short, sharp protrusion (Fig. 5C, G , arrows). Female vulvae (Fig. 5K ): simple, valves prominent, the right valve slightly larger than the left valve. DNA barcode. The GenBank accession number of the COI barcode of the paratype is OP174623 (voucher code CUMZ-D00148). Habitat. Found under leaf litter and inside a rotten log. Distribution. Known only from the type locality in Lampang Province, Thailand (Fig. 7 ).