Stenothemus singularicollis (Pic, 1933) Yang & Yang & Liu, 2021

Yang, Yuxia, Ge, Shujuan, Yang, Xingke & Liu, Haoyu, 2021, Taxonomic revision of the species of Stenothemus from Southwest China (Coleoptera, Cantharidae), with the descriptions of five new species, European Journal of Taxonomy 757 (1), pp. 1-36 : 20-21

Stenothemus singularicollis (Pic, 1933) comb. nov.

Figs 5D‒E , 7C , 12A

Podabrinus singularicollis Pic, 1933a: 5 .

Stenothemus melleus Švihla, 2005: 103 , fig. 71. syn. nov.

Pseudoabsidia singularicollis – Wittmer 1969: 128.

Athemellus singularicollis – Wittmer 1972: 124.

Lycocerus singularicollis – Kazantsev & Brancucci 2007: 253.

Material examined

Holotype of Podabrinus singularicollis

CHINA • ♀; [p] “Kina // S. Kansu”, “Sven Hedins // Exp. Ctr. Asien // Dr Hummel”, [h] “ Podabrinus // singularicollis // n. sp.”, [p] “HOLOTYUS”, [h-p] “ Stenothemus // singularicollis (Pic) // det. Y. X. Yang, 2009”; NHMH.

Holotype of Stenothemus melleus

CHINA • ♂; [p] “China: Sichuan Prov. // Quingchenghou mts. 1500 m // 70 km W Chengdu, 15.‒22.x. // S. Murzin lgt. 2004”, [p] “HOLOTYUS // Stenothemus // melleus sp. nov. // V. Švihla det. 2005”; NMPC.

Additional material

CHINA ‒ Gansu • 1 ♂; Tianshui, Naiji, Guanyin ; 12 Sep. 2020; J. Li leg.; MHBU . ‒ Shaanxi • 1 ♂; “ China, Shaan Xi, Qin Ling Mountain , Hou Zhen Zi , 33.8463° N, 107.8333° E, 1350 m, 26 Aug. 2013, Ruan leg.”; IZAS • 2 ♂♂, 1 ♀; Hanzhong, Mianxian, Miaoping ; 7 Oct. 2020; J. Li leg.; MHBU • 8 ♂♂, 1 ♀; Hanzhong, Lueyang, Wulongdong ; 11 Oct. 2020; J. Li leg.; MHBU • 1 ♀; Hanzhong, Liuba, Huoshaodian ; 4 Oct. 2020; J. Li leg.; MHBU .

Descriptive notes

Body length (both sexes): 8.5‒12.0 mm; width: 1.8‒2.5 mm.

Female ABDOMINAL STERNITE VIII ( Fig. 7C ). Moderately narrowed posteriorly, lateroapical angles obtusely rounded, posterior margin widely and roundly emarginate in middle and feebly sinuate on both sides,

behind the notch with a membrane which is sclerotized and triangularly bilobed at apex.

INTERNAL ORGAN OF REPRODUCTIVE SYSTEM ( Fig. 12A ). Vagina stout, with median oviduct situated at ventroapical part, vagina abruptly narrowed in apical part and extended into a short duct which diverticulum and spermathecal duct are arising from; diverticulum extremely long, about 0.58 times adult body length, evenly thinned apically, slender tube-shaped and spiral; spermathecal duct long but much shorter than diverticulum; spermatheca slender tube-shaped and spiral, thinner than spermathecal duct and nearly as long as diverticulum, with basal part extended into a short tube, where accessory gland opens. Accessory gland thin in basal part, and the remainder moderately thin, much shorter than spermatheca.

Distribution

China (Gansu, Sichuan, Shaanxi). New record for Shaanxi Province.

Remarks

Having examined the holotypes of Podabrinus singularicollis ( Fig. 5D ) and Stenothemus melleus ( Fig. 5E ), as well as a large series of additional specimens available, we are unable to find differences justifying their separation, which has led us to consider all the examined specimens to be conspecific. Therefore, we suggest the latter species should be synonymized with the former, which should be called S. singularicollis according to the structure of the aedeagus and simple claws. Additionally, the female reproductive system and abdominal sternite VIII of this species are described for the first time.

Figures

Fig. 5. Habitus, dorsalview.A. Stenothemus jindraiŠvihla, 2004, holotype, ♂ (NMPC).B. S. minutissimus (Pic, 1933) comb. nov., holotype, ♂ (MNHN). C. S. tryznai Švihla, 2004, holotype, ♂ (NMPC). D. S. singularicollis (Pic, 1933) comb. nov., holotype, ♀ (NHMH). E. S. melleus Švihla, 2005 syn. nov., holotype, ♂ (= S. singularicollis) (NMPC). Scale bars = 1.0 mm.

Fig. 7. Abdominal sternite VIII of female, ventral view. A. Stenothemus minutissimus (Pic, 1933) comb. nov. (IZAS, Sichuan). B. S. tryznai Švihla, 2004 (IZAS, Sichuan). C. S. singularicollis (Pic, 1933) comb. nov. (MHBU, Shaanxi). D. S. gracilis Y. Yang & X. Yang sp. nov., paratype (IZAS IOZ(E) 225787). E. S. flavicollis Y. Yang & S. Ge sp. nov., paratype (MHBU HBU(E) 410039). F. S. laticornis Y. Yang & H. Liu sp. nov., paratype (MHBU HBU(E) 410047). Scale bars = 1.0 mm.

Fig. 12. Female reproductive system, ventral view. A. Stenothemus singularicollis (Pic, 1933) comb. nov. (MHBU, Shaanxi). B. S. gracilis Y. Yang & X. Yang sp. nov., paratype (IZAS IOZ(E) 225787). C. S. flavicollis Y. Yang & S. Ge sp. nov., paratype (MHBU HBU(E) 410039). D. S. laticornis Y. Yang & H. Liu sp. nov., paratype (MHBU HBU(E) 410047). Abbreviations: see Material and methods. Scale bars = 0.5 mm.