Rhagonycha longicornis Y. Yang, Xiao & Liu 2024, sp. nov.
Creators: name: Xiao, Yun-Feng
name: Liu, Hao-Yu
name: Yang, Xing-Ke
name: Yang, Yu-Xia
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Cantharidae
Rhagonycha
Rhagonycha longicornis

description: Rhagonycha (s.str.) longicornis Y. Yang, Xiao & Liu, sp. nov.
(Figs 23C, 24C, 25A‒B, 26A‒C, 38)
Type material. HOLOTYPE: ♂ (MHBU), CHINA, Xizang: Mêdog, Hanmi, 28.VII.2013, leg. X.L. Bai & J.S. Shan. PARATYPES: CHINA, Xizang: 1♂, 1♀ (MHBU), same data as the holotype; 4♂♂, 20♀♀ (MHBU), same locality as the holotype, 2380 m, 9.VIII.2016, leg. G.D. Ren; 2♂♂, 2♀♀ (IZAS), Mêdog, Hanmi, No 1 Bridge, 1300‒ 2380 m, 10.VIII.2003, leg. H.J. Xue & X.P. Wang; 1♀ (IZAS), Nyingchi, Pêlung, 2100 m, 1.IX.2005, leg. X.L. Chen; 1♀ (IZAS), Zayü, Gujing, 1.VI.1973, leg. F.S. Huang; 4♀♀ (IZAS), Bomi, Yi’ong, 2300 m, 14.VIII.1983, leg. Y.H. Han; 1♂ (IZAS), same data as the preceding, 15.VIII.1983; 2♂♂, 1♀ (CAU), Yi’ong, 2300 m, 29.VII.1978, leg. F.S. Li; 1♂ (CAU), same data as the preceding, 30.VII.1978; 1♀ (CAU), same data as the preceding, 31.VII.1978.
Differential diagnosis. It looks similar to Rh. spinosa in the shape of aedeagus, but can be distinguished from the latter by the following characters: legs and scutellum yellow, while black in Rh. spinosa (Fig. 6A); aedeagus: ventral process of each paramere feebly thinned near apex in ventral view, while obviously widened in Rh. spinosa (Fig. 5D); conjoint dorsal plate of parameres feebly longer than ventral processes in lateral view, while obviously longer in Rh. spinosa (Fig. 5F).
Description. Body length: 7.5‒8.4 mm (7.6 mm in holotype); width: 1.5‒2.1 mm (1.7 mm in holotype).
Male (Fig. 25A). Coloration. Body yellowish orange except for the following parts: antennae black, except antennomeres Ⅰ–II yellowish orange, elytra pale yellow, almost transparent. Surface sparsely and finely yellow pubescent, anterior margin of clypeus fringed with pale bristles.
Head rounded, surface densely and finely punctate; eyes moderately protruding, head width across eyes 1.1 times wider than anterior margin of pronotum; terminal maxillary palpomeres subtriangular, widest at apical third; antennae extending to basal 3/4 length of elytra when reclined, antennomeres II shortest, about 2.7 times as long as wide at apices, III about 1.8 times longer than II, VI longest, XI feebly longer than X and pointed at apices.
Pronotum transverse, about 1.1 times as long as wide, anterior margin rounded, anterior angles subrounded, lateral margins feebly diverging posteriorly, posterior margin nearly straight, posterior angles sub-rectangular, disc strongly convex on posterolateral parts, surface finely and sparsely punctate.
Elytra with lateral margins feebly diverging posteriorly, about 3.5 times as long as humeral width, 4.0 times longer than pronotum, surface finely rugulose-lacunose, almost lustrous at basal parts.
Aedeagus moderately swollen laterally near middle (Fig. 26A, B); ventral processes of parameres abruptly thinned apically near bases, slender and thinned at apices, bent to each other in ventral view (Fig. 26A), and almost straight in lateral view, with apices widened and rounded (Fig. 26C); conjoint dorsal plate feebly longer than ventral process (Fig. 26C), with apical margin feebly emarginate in middle, lateral margins feebly diverging apically from middle, latero-apical angles widely rounded in dorsal view (Fig. 26B), nearly straight in lateral view (Fig. 26C); emargination between ventral process and conjoint dorsal plate about 2/5 length of aedeagus (Fig. 26C).
Female (Fig. 25B). Similar to male, but with larger and stouter body, eyes less protruding, head width across eyes about 0.8 times as wide as anterior margin of pronotum, antennae thinner and shorter, extending to apical third length of elytra when reclined, pronotum wider and about 1.3 times as wide as long, anterior margin less arcuate, disc feebly convex on posterolateral parts, elytra about 3.3 times as long as humeral width, with lateral margins moderately diverging posteriorly.
Internal organ of reproductive system (Fig. 23C): vagina stout and abruptly thinned at ventroapical portion into a short and feebly stout tube, where diverticulum and spermathecal duct arising separately; diverticulum short and spiral, progressively thinned apically; spermathecal duct nearly as short as the apical tube of vagina; spermatheca provided with a spiral tube, progressively thinned apically and twice longer than diverticulum; accessory gland moderately long, about 1.5 times as long as spermatheca.
Abdominal sternite VIII (Fig. 24C) strongly narrowed posteriorly, widely triangular at latero-apical angles, and shallowly emarginate on both sides of posterior margin, with the portion between lateral emarginations truncate at apex and nearly horizonital with apices of latero-apical angles.
Etymology. The specific name is derived from the Latin longus (long), and cornus (horn), and referring to its long antennae.
Distribution (Fig. 38). China (Xizang).
description: Published as part of Xiao, Yun-Feng, Liu, Hao-Yu, Yang, Xing-Ke & Yang, Yu-Xia, 2024, Taxonomic review of the Rhagonycha flava species group (Coleoptera, Cantharidae), with descriptions of fourteen new species from China, pp. 1-69 in Zootaxa 5534 (1) on pages 42-43, DOI: 10.11646/zootaxa.5534.1.1, http://zenodo.org/record/14023514