Fissocantharis sexcostata Y. Yang & X. Yang

Yang, Yuxia, Li, Limei, Guan, Kaile & Yang, Xingke, 2015, Taxonomy of Fissocantharis Pic (Coleoptera, Cantharidae) from Guangxi, China, with descriptions of six new species, ZooKeys 489, pp. 95-123 : 100-101

Taxon classification Animalia Coleoptera Cantharidae

Fissocantharis sexcostata Y. Yang & X. Yang sp. n. Figs 1D, 4D‒F, 8C, 9C

Type material.

Holotype ♂ (IZAS): CHINA: Guangxi, Jinxiu, Huawangshanzhuang, 600m, 20.V.1999, leg. M.Y. Gao. Paratypes: 1♂, 2♀♀ (IZAS): same data as the holotype; 2♂♂ (IZAS): same locality and date, leg. Y.Z. Zhang; 1♂ (IZAS): same locality and date, leg. H. Xiao; 1♀ (IZAS): same locality and date, leg. W. Z. Li; 1♂ (IZAS): same locality and date, leg. H.X. Han; 1♀ (IZAS): same locality and date, leg. X.K. Li; 1♀ (IZAS): same locality and date, leg. D.C. Yuan.

Description.

Male (Fig. 1D). Head black, mouthparts blackish brown, light brown at bases of mandibles and labium, antennae black, orange at antennomeres I‒II and ventral sides of III, prothorax orange, pronotum with a large inverse-triangular and a slightly small triangular black markings in middle of anterior and posterior parts of disc respectively, two markings almost conjoint, scultellum black, elytra dark purple, with weak metallic shine, legs black, yellow at pro-coxae, trochanters and femora and meso-trochanters and bases of femora, meso- and metasterna and abdomen black. Body densely covered with short decumbent light brown pubescence, also mixed with slightly long semierect pubescence along anterior margin of labrum and on disc of elytra.

Head subquadrate, temples evenly narrowed posteriorly, surface semilustrous, finely and densely punctate; eyes moderately protruding, head breadth across eyes dis tinctly wider than anterior margin of pronotum; maxillary palpomeres IV longer than wide, widest at apical one-third, arcuate and sharp at apical parts of inner margins; antennae almost extending to apical one-third length of elytra, antennomeres II nearly as long as wide at apices, III‒X slightly widened apically, nearly long-triangular, the whole length of III‒VII and basal two-thirds length of VIII each with a longitudinal ridge along outer margin, IV slightly longer than III, XI parallel-sided, slightly longer than X and pointed at apices.

Pronotum about 1.10 times longer than wide, widest near base, anterior margin rounded, anterior angle rounded, lateral margins slightly sinuate and diverging posteriad, posterior angle nearly rectangular, posterior margin arcuate and slightly bordered, disc distinctly convex on posterolateral parts, surface semilustrous, punctate like that on head.

Elytra about 3.4 times longer than pronotum, 3.0 times longer than humeral width, lateral margins nearly parallel, disc surface semilustrous, rugulose-lacunose and finely punctate.

All tarsal claws bifid, upper claws nearly as long as lower claws.

Aedeagus (Fig. 4D‒F): conjoint dorsal plate of parameres moderately reduced, distinctly shorter than ventral process, with apical margin tapered apically; ventral process of each paramere evenly narrowed apically, largely hooked at apex.

Female. Similar to male, but eyes not so protruding; antennae uniformly black, antennomeres III‒X nearly parallel-sided, III‒VIII without ridges; pronotum slightly wider, about 1.12 times longer than wide, lateral margins sinuate, moderately diverging posteriad, moderately convex at posterolateral parts of disc, legs orange at pro-coxae and trochanters. Abdominal sternite VIII (Fig. 8C) slightly emarginated on both sides of posterior margin, middle part between lateral emarginations slightly arcuate, latero-apical angles narrowly rounded. Internal organ of reproductive system (Fig. 9C): vagina stout and abruptly narrowed and extended into a long duct above median oviduct; diverticulum and spermathecal duct arising from the end of the long duct of vagina; diverticulum slightly long, thin and spiral; spermathecal duct distinctly thicker and shorter than diverticulum; spermatheca composed of a spiral tube which is distinctly longer than diverticulum, provided with a long and thin accessory gland which is slightly longer than the spiral tube of spermatheca; median oviduct situated in middle of vagina.

Body length: 6.0‒10.0 mm; width: 1.2‒2.0 mm.

Diagnosis.

This species is similar to Fissocantharis sinensis , but can be easily differentiated by the antennomeres III‒VIII with longitudinal ridges along outer margins in male; aedeagus: conjoint dorsal plate of parameres moderately reduced.

Distribution.

China (Guangxi).

Etymology.

The specific name is derived from Latin sex- (six) and costatus (ridged), referring to its antnnomeres III‒VIII with longitudinal ridges (six ridges in total) along outer margins in male.

Remarks.

Sometimes the pronotum is uniformly orange, without any black markings, and this variation always occurs on the females.