Stenothemus longicornis Y. Yang & H. Liu, 2021

Yang, Yuxia, Ge, Shujuan, Yang, Xingke & Liu, Haoyu, 2021, Review of the species of Stenothemus from Southeast China (Coleoptera, Cantharidae), European Journal of Taxonomy 744, pp. 119-144 : 138-139

Stenothemus longicornis Y. Yang & H. Liu sp. nov.

urn:lsid:zoobank.org:act:642A908A-1F99-44DD-BC37-142F864A35E2

Figs 2D , 4G‒I

Differential diagnosis

The new species resembles S. hajeki Švihla, 2011 (from N Yunnan, China), but differs in the following characters: antennae without impressions on middle antennomeres (with small oval impressions on antennomeres IV‒XI in the latter), pronotum obviously longer than wide (nearly as long as wide in the latter); elytra more elongate, about 3.5 times humeral width (3.2 times in the latter); aedeagus: parameres approaching each other (far from each other in the latter).

Etymology

The specific name is derived from the Latin ‘ longus ‘, meaning ‘long’, and ‘ cornus ‘, meaning ‘horn’, and referring to its long antennae.

Material examined

Holotype CHINA • ♂; Guangdong, Nanling, Ruyuan ; 8 Apr. 2009; L. Gao leg.; MHBU HBU(E)410001 .

Description

Male ( Fig. 2D )

MEASUREMENTS. Body length: 6.8 mm; width: 1.4 mm.

COLORATION. Body black, mouthparts light brown, reddish brown at apices of mandibles, more or less darkened at maxillary and labial palpi, prothorax reddish brown, femora light brown at basal. Body densely covered with short, recumbent yellow pubescence.

HEAD. Subquadrate, surface densely and finely punctate, each side with smooth and rectangular impression behind antennal socket; eyes strongly protruding, head width across eyes about 1.4 times as wide as pronotum; terminal maxillary palpomeres long-triangular, widest at basal two-thirds; antennae quite long, obviously exceeding apices of elytra; antennomeres II slightly longer than wide at apices, III about 2.6 times as long as II, III‒XI flattened and subparallel-sided, IV widest, V to XI gradually narrowing towards apex, VIII longest, XI slightly longer than X, pointed at apex.

PRONOTUM. Subquadrate, about 1.2 times as long as wide, anterior margin rounded, anterior angles obtuse, subrounded, lateral margins nearly parallel and slightly sinuate, posterior margin straight and finely bordered, posterior angles obtusely rectangular, disc strongly convex on posterolateral parts, surface finely and densely punctate.

ELYTRA. Parallel-sided, about 3.5 times as long as humeral width, 4.8 times as long as pronotum, surface densely and finely punctate, with hardly visible longitudinal costae.

AEDEAGUS ( Fig. 4G‒I ). Moderately swollen laterally at basal part, strongly contracted in diameter apically; basal piece nearly as long as dorsal plate of each paramere, with a large, bifurcate conjoint middle nodule at base of ventral side; ventral processes of parameres approaching each other, short and slightly thickened apically, bent ventrally in lateral view; dorsal plate slightly longer than ventral process, strongly narrowed near base, approaching to each other, apex acute and directed ventrally; apical part of laterophyses separate from each other, apex wide-triangular and bent dorsally, feebly exceeding middle emargination between dorsal plates.

Female

Unknown.

Distribution

China (Guangdong).

Figures

Fig. 2. Male habitus, dorsal view. A. Stenothemus biimpressiceps (Pic, 1930) comb. nov., nontype specimen from Zhejiang (IZAS). B. S. flavus Y. Yang & X. Yang sp. nov., holotype, ♂ (IZAS, IOZ(E)1123159). C. S. limbatipennis (Pic, 1926) stat. rev. et comb. nov., non-type specimen from Zhejiang (MHBU). D. S. longicornis Y. Yang & H. Liu sp. nov., holotype, ♂ (MHBU, HBU(E)410001). Scale bars: 1.0 mm.

Fig. 4. Aedeagus (A, D, G = ventral view; B, E, H = dorsal view; C, F, I = lateral view). A‒C. Stenothemus nigriceps (Wittmer, 1955) comb. nov. (MHBU). D‒F. S. flavus Y. Yang & X. Yang sp. nov. (IZAS, IOZ(E)1123159). G‒I. S. longicornis Y. Yang & H. Liu sp. nov. (MHBU, HBU(E)410001). Scale bars: 1.0 mm.