Stenothemus biimpressiceps Yang & Yang & Liu 2021, comb. nov.
Creators: name: Yang, Yuxia
name: Ge, Shujuan
name: Yang, Xingke
name: Liu, Haoyu
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Cantharidae
Stenothemus
Stenothemus biimpressiceps

description: Stenothemus biimpressiceps (Pic, 1930) comb. nov.
Figs 1A, 2A, 3A‒C, 6A, 8A
Cantharis biimpressiceps Pic, 1930: 78.
Material examined
Holotype CHINA • ♀; [h] “Chine”, [p] “81”, [h-p] “Déterminé par // Heyden”, [h] “sp.ignota”, [h] “ biimpressiceps // n. sp.”, [p] “HOLOTYPUS”, [h-p] “ Stenothemus // biimpressiceps (Pic) // det. Y. X. Yang, 2009”; MNHN.
Other material
CHINA – Anhui • 1 ♂; Yaoluoping National Natural Reserve; Jul. 2015; J. Fang leg.; MHBU. – Hubei • 1 ♂; Baokang; 8 Apr. 2011; H.F. Huang leg.; IZAS • 1 ♂; Yichang, Dalaoling; 1 May 2014; J.Y. Su leg.; MHBU. – Jiangxi • 1 ♀; date and collector unknown; IZAS. – Zhejiang • 1 ♂, 2 ♀♀; Anji, Longwangshan; 450 m a.s.l.; 11 May 1996; H. Wu leg.; IZAS • 1 ♂; same locality and collector as for preceding; 12 May 1996; IZAS.
Redescription
MEASUREMENTS. Body length (both sexes): 10.0‒14.0 mm; width: 2.5‒3.5 mm.
Male (Fig. 2A)
COLORATION. Body yellowish brown, sometimes with brown markings on disc of pronotum, mouthparts light brown, reddish brown at apices of mandibles, antennae, tarsi, tibiae and apices of femora dark brown. Body densely covered with yellow pubescence, sparsely on pronotum.
HEAD. Subquadrate, surface densely and finely punctate, each side with smooth and rectangular impression behind antennal socket; eyes strongly protruding, head width across eyes 1.2 times as wide as pronotum; terminal maxillary palpomeres long-triangular, widest in middle; antennae filiform, extending to twothirds length of elytra; antennomeres II about 1.5 times as long as wide at apices, III about 1.5 times as long as II, VII longest, XI slightly longer than X, pointed at apex.
PRONOTUM. Subrounded, nearly as wide as long, anterior margin arcuate, anterior angles rounded, lateral margins sinuate, posterior margin nearly straight and narrowly bordered, posterior angles sharp and protruding, disc distinctly convex on posterolateral parts, surface finely and densely punctate.
ELYTRA. Nearly parallel-sided, about 3.5 times as long as humeral width, 5.2 times as long as pronotum, surface finely and densely punctate, with weakly indicated longitudinal costae.
AEDEAGUS (Fig. 3A‒C). Strongly swollen laterally at basal part, shrunk apically in diameter; basal piece nearly as long as dorsal plate of each paramere, with a large, bifurcate conjoint middle nodule at base of ventral side; ventral process of each paramere nearly parallel to each other, short and distinctly thickened apically, bent dorsally in lateral view; dorsal plate slightly longer than ventral process, abruptly narrowed in middle and wide-triangularly protuberant at apical part, near to each other at basal part, apex acute and folded ventrally; apical parts of laterophyses depressed and separate from each other, apex acute and bent dorsally, not reaching middle emargination between dorsal plates.
Female (Fig. 1A)
Similar to male, but eyes less protruding, antennae shorter and roughly extending to elytral mid-length; pronotum slightly wider than long, elytra about 3.0 times as long as humeral width.
ABDOMINAL STERNITE VIII (Fig. 8A). Obliquely narrowed posteriorly, latero-apical angles obtusely rectangular, posterior margin deeply and roundly emarginate in middle and feebly sinuate on both sides, behind notch with membrane which presents small longitudinal sclerite at center.
INTERNAL ORGAN OF REPRODUCTIVE SYSTEM (Fig. 6A). Vagina stout, with median oviduct situated at ventroapical part, diverticulum and spermathecal duct arising from apex; diverticulum moderately long, about 0.12 times body length, evenly thinned apically, slender tube-shaped and spiral; spermathecal duct much shorter than diverticulum; spermatheca slender tube-shaped and spiral, obviously thinner than spermathecal duct and slightly longer than diverticulum, with basal part extended into short tube, where accessory gland opening. Accessory gland thin and obviously shorter than spermatheca.
Remarks
This species was originally described based on a single female type (Pic 1930). During our study, the type was located at MNHN, as well as some additional specimens, making it possible for us to study this species in detail. The morphological characters, especially the structure of the aedeagus, show that it belongs to Stenothemus and not to Cantharis.
Distribution
China (Anhui, Hubei, Zhejiang, Jiangxi).
description: Published as part of Yang, Yuxia, Ge, Shujuan, Yang, Xingke & Liu, Haoyu, 2021, Review of the species of Stenothemus from Southeast China (Coleoptera, Cantharidae), pp. 119-144 in European Journal of Taxonomy 744 on pages 121-124, DOI: 10.5852/ejt.2021.744.1307, http://zenodo.org/record/4690236