Scutellathous habenularis Liu & Jiang

Liu, Zhen & Jiang, Shi-hong, 2019, The genus Scutellathous Kishii, 1955 (Coleoptera, Elateridae, Dendrometrinae) in China, with description of three new species, ZooKeys 857, pp. 85-104 : 85

Scutellathous habenularis Liu & Jiang sp. nov. Figs 1, 2, 3, 4, 5, 12

Type locality.

Yunnan, China.

Material examined.

Holotype: ♂ ( MHBU), labels: 1) Yunnan Prov., Gaoligong Mts (2000 m, 25°59'8.81"N 98°49'1.40"E) (高黎贡山), 2012.VII.23, leg. Ji-shan Xu et Ling-xiao Chang, Shenzhen Polytechnic; 2 ) Holotype, Scutellathous habenularis sp. nov., Liu et al. 2019; 3) No. 20180353. Paratype: 1♀ ( MHBU), labels: 1) Yunnan Prov., Gaoligong Mts (2000 m, 25°59'8.81"N 98°49'1.40"E) (高黎贡山), 2012.VII.23, leg. Ji-shan Xu et Ling-xiao Chang, Shenzhen Polytechnic ; 2) Paratype, Scutellathous habenularis sp.nov., Liu et al. 2019; 3) No. 20180354.

Diagnosis.

Body bright red-brown, shiny; anterior edge of head truncate in dorsal view; antennae reaching apices of pronotal hind angles, nearly cylindrical from antennomere 6 onward, attached apico-dorsally, antennomere 3 1.8 times as long as 2 and nearly as long as 4; pronotum with hind angles divergent posterad, disc flat medially with only trace of a glabrous non-furrowed longitudinal line, shiny with umbillicate punctures; scutellar shield 1.1 times longer than wide; aedeagus with penis reaching to apex of parameres, penis gradually narrowed to pointed apex.

Scutellathous habenularis is similar to S. yamashitai Arimoto 1992, but is distinguished by the glabrous non-furrowed longitudinal line throughout the length of the pronotum (with shallow median impression only on basal half of the pronotum in S. yamashitai ), the obtuse anterior angles of the pronotum (acute in S. yamashitai ), and the penis reaching beyond parameres (penis shorter than parameres in S. yamashitai ).

Description.

Male (holotype). Body (Fig. 1 a–c) length 14.8 mm, width 3.5 mm; bright red-brown on head, pronotum (except hind angles), and elytra near scutellar shield; ventral surfaces and legs brown-black, and antennae brown (except antennomere 1-2 brown-black); dorsal pubescence yellow, suberect, shorter, denser, and pointed anterad on pronotum and head, longer, sparser, semi-recumbant, pointed posterad on elytra, ventral pubescence more recumbent and thinner.

Head. Anterior edge truncate in dorsal view (Fig. 2e), spaces between punctures shiny and 1-2 puncture diameters wide, punctures larger, denser, coarser in deep triangular depression (Fig. 2c); eye semi-spherical, ocular index 71; last segment of maxillary palpus 1.6 times longer than wide; antennae (Fig. 3e), reaching apices of pronotal hind angles, antennomeres 3 to 10 weakly serrate, nearly cylindrical from antennomere 6 onward, attached apico-dorsally, antennomere 1 robust, longest and subclavate, antennomere 2 shortest, obconic, 1.4 times longer than wide, antennomere 3 elongated triangular, 1.8 times as long as 2 and nearly as long as 4, antennomere 11 oblong, 5.0 times longer than wide, 1.1 times longer than antennomere 3, proportions of antennomeres as follows: 100; 52; 93; 95; 95; 94; 82; 96; 87; 82; 98.

Thorax. Pronotum (Fig. 2e) nearly 1.2 times longer than wide, parallel-sided in dorsal view, except abruptly concave at anterior end and strongly concave before hind angles, widest at hind angles; disc flat medially with only trace of a glabrous non-furrowed longitudinal line, shiny with umbillicate punctures, spaces between punctures 1 to 2 puncture diameters wide medially (Fig. 3a), strongly umbillicate with interspaces 0.3 puncture diameter wide laterally and posteriorly; hypomera (Fig. 2d) with spaces between punctures narrower than half puncture diameter wide; hind angles (Fig. 2e) divergent, apex upheaved and obtuse, with carina extending only to basal 1/5 of pronotum along sides; sublateral incisions small. Prosternum shiny and sparsely, irregularly punctate, interspaces 1 to 4 times puncture diameters wide; anterior lobe (Fig. 2a) 2.3 times wider than long, with sparse, fine punctures. Prosternal process gradually narrowed to pointed apex. Meso- and meta-ventrites with stronger and denser punctures than those on prosternum, smooth. Metaventrite furrowed medially on anterior 3/4.

Scutellar shield. 1.1 times longer than wide (Fig. 2f), widest posterad, narrowing anterad gradually at sides, hind margin arched, weakly emarginate anteriorly; disc convex with umbillicate punctures medially, spaces between punctures 2-3 puncture diameters wide, strongly rugose-punctate near edges, with short yellow, outwardly-oriented pubescence laterally.

Elytra. Slender (Fig. 1a), 2.7 times longer than wide, 2.8 times longer and 1.1 times wider than prothorax respectively, widest at anterior one-fifth, parallel-sided, gradually narrowing to apex from midlength (Fig. 3b) with punctate striae, interpuncture spaces about 2-3 puncture diameters wide, interstriae slightly elevated, mostly smooth with smaller, shallower and sparser punctures than punctures within striae, interpuncture spaces about 3 puncture diameters wide, weakly and transversely rugulose anteriorly.

Legs. Slender (Fig. 3f); tarsomere 3 with a larger lobe beneath than tarsomeres 2, tarsomere 4 shortest; metacoxal plate (Fig. 3c) with mesal parts subparallel-sided, then abruptly strongly narrowed into at lateral one-fourth.

Abdomen. Surfaces of sternites III–VII like metaventrite, with punctures and pubescence more regular and evenly distributed laterally; sternite VII (Fig. 3d) broadly rounded, elongate, 1.7 times wider than long, punctures becoming bigger posteriorly.

Genitalia. Aedeagus (Fig. 4 a–c) slender, weakly sclerotized; penis reaching to apex of parameres, gradually narrowed to pointed apex; parameres thin, strongly sinuate laterally at midlength, tapered to rounded apex.

Female. Like male (Fig. 5a), except larger (length: 15.9 mm, width: 3.9 mm), antennae shorter (short of pronotal hind angle apices by half length of last antennomere) and pronotum strongly arched laterally and narrowed anteriorly in dorsal view. Bursa copulatrix (Fig. 5b) weakly sclerotized (it dissolved after being macerated in 10% NaOH for 10 hours) with a circular thorny line and without thorny plates. Ovipositor (Fig. 5c) 2.3 times longer than wide, with short styli.

Larva. Unknown.

Etymology.

The name of the new species is derived from the Latin " habenularis " (Latin for “strip”) referring to its hind coxae abruptly and strongly narrowed into a strip at lateral one-fourth part.

Distribution.

China: Yunnan (Fig. 12).

Biology.

Collected around the elevation of 2000 m in subtropical evergreen forest.

Remarks.

Its bursa copulatrix resembles Ohirathous in sharing a circular thorny line, but differs in lacking thorny plates. Other characters (carina on hind angles extending only basal 1/5 of pronotal length; antennomere 3 2.1 times as long as 2; shape of male genitalia; shape of female pronotum; only tarsomeres 2 and 3 lobed beneath) are consistent with the diagnosis of genus Scutellathous . Structures of the bursa copulatrix are diverse within Scutellathous species - from five thorny plates ( S. comes , S. porrecticollis , S. sasajii , S. shikokuanus ) or four ( S. seinoi ) thorny plates and without thorny line to no thorny plates but with thorny line in S. habenularis . The bursa copulatrix structure of Ohirathous (a circular thorny line and two thorny plates) falls within the range of variation observed in Scutellathous and does not support distinction of Ohirathous from Scutellathous . Unfortunately, male genitalia of Ohirathous is unknown. Further phylogenetic study is needed to understand the monophyly of Ohirathous and the relationship between these two genera.