Didrepanephorus Wood-Mason, 1878

Genus Didrepanephorus Wood-Mason, 1878 View in CoL

Denis Keith ( France) - https://zoobank.org/ 841FF99A-A032-4703-86AD-2E38DC0CC92E - https://orcid.org/0000-0002-2554-4325

Didrepanephorus dangvani n. sp.

( Fig. 1 -8)

ZooBank: https://zoobank.org/ 70D47A4D-7040-45B0-9452-70500B3C9354

Holotype, ♂, // VIETNAM, Hà Giang Prov. / Minh Tân , 1300 m / V.2024, local collectors // ( MHNG).

Paratypes

- same dataasfor the holotype, 1 ♀ ( NHMG) , 1 ♂ ( IEBR) , 2 ♂ & 2 ♀ ( GSC) , 1 ♂ ( DKC) ;

- // VIETNAM, Lào Cai Prov. / Bát Xát Distr. , Y Tý Com., Bát Xát Nature Res. / 30. V .2022, N. T. Pham leg. //, 1 ♀ ( IEBR) .

Etymology. – We dedicate the species to Mr Đặng Ngọc Văn (Bảo Lộc city, Vietnam). Interested in insects since child, he is the major collector of insects for Vietnam allowing the discovery of many new species and a better understanding of its fauna.

Description of the holotype

General morphology and coloration ( Fig. 1). –Body oval and convex; length 18 mm ( 24 mm including mandibles), 9 mm maximum width; head, pronotum, scutellum, abdomen and legs dark brown; elytra light brown with lateral margins, suture and a stripe connecting humeral to apical umbones black; body covered by uniform dense and short setae yellowish.

Head. – Clypeus flat, trapezoidal, anterior margin straight; anterior angles rounded, sides strongly convergent anteriorly and expanded in basal half, concave near middle, then almost subparallel in apical half; with dense fine punctures, not punctured near anterior margin, frontal-clypeal suture almost absent, represented by a short carina at each side; frons and vertex with dense large punctures and dense, erect long setae; eye-canthus wide and truncate at outer margin not extends beyond outermost point of eye, anterior angle nearly right; antennal scapus brown, base of antennal club dark brown, gradually changed fulvous to apex, length of antennal club distinctly longer than antennomeres 2 - 7 combined; labrum exposed, anterior margin deflected, dorsal surface sparsely microsculptured, with sparse, short and long setae; mandible dark brown, broadest at base, lower margin deeply constricted before basal tooth, apex sharply bent upwards ( Fig. 4); maxillary palps and labial palps dark brown; mentum with dense punctures and long erect setae, anterior margin slightly concave in middle; gula dark brown, glabrous and matt.

Pronotum. –Strongly convex, 1.55timesas wide aslong,widestnearmiddle; anterior margindistinctly bisinuate;anterior marginal membrane distinct, obsolete before reaching anterior angle; lateral margins feebly concave and convergent posteriorly in basal half, roundly and broadly curved at middle, convergent anteriad in apical half; posterior margin broadly protruding in middle; basal marginal line interrupted before scutellum, all other marginal lines completed; anterior angle moderately protruding, posterior angle slightly protruding, both blunt at apex; surface with dense small punctures, rugopunctate along lateral margin, and disc with indistinct longitudinal medial line; most areas of disc with rather dense semierect short setae,setae on lateral portions being longer.

Scutellum. – Triangular, lateral margin slightly curved, apex rounded, surface with dense large punctures, glabrous.

Elytra. – Convex, almost as wide as long, and widest at middle; striae and interval unrecognizable the surface coarsely, with sparse, shallow, round fine punctures and dense, short, semierect setae; humeral umbone and apical umbone convex; epipleura glabrous.

Ventral thoracic surface. – Base of ventral prothoracic and anterior half of ventral metathoracic surfaces with dense long hairs; anterior half of ventral prothoracic and posterior half of ventral mesothoracic surfaces with erect short setae; prosternal process small, horizontally broad, and shield-liked with a medial carina.

Propygidium. – Surface uniformly granulose, with dense, semierect short setae.

Pygidium . – Convex, disc finely microsculptured, setosus as in propygidium.

Abdomen. – Distinctly curved in lateral view, abdominal ventrites 1-4 abbreviated; with dense round punctures and semierect long setae; posterior margin of abdominal ventrite 6 broadly and distinctly concave medially, with a row of dense, semierect long setae.

Legs. – With moderately dense, erect long setae; femora with dense punctures; tibiae with dense, coarse and irregular punctures. Inner protarsal claw simple and thickened, outer protarsal claw smaller and sharp at apex; outer meso- and metatarsal claws widely and deeply split into two branches respectively, the upper branches thinner and sharper; in outer mesotarsal claw the two branches equal in length, in outer metatarsal claw the upper branch slightly longer than the lower branch; inner meso- and metatarsal claws more curved than the outer ones; protibia with three distinct and acute teeth; protibial spur situated at the level of middle protibial tooth, vertically oriented forwards; meso- and metatibiae bidentate at apical edges, the upper tooth in mesotibia distinctly protruding; protarsus strongly thickened; protarsomeres 2 - 4 abbreviated; protarsomere 4 ventrally with a short blunt protrusion; meso- and metatarsomeres 4 each with an acute ventroapical protrusion, each protrusion with a pair of spines at base; tarsomeres 5 of all legs with a small and blunt ventral protrusion in basal third.

Aedeagus. – As in Fig. 3, 7, 8 composed by long phallobase narrowing toward distally, evenly curved in lateral view and paramera lobose, fused basally, with undulated lateral margins and distal margin of right paramere medially with two parallel short processes.

Variability of male paratypes. – Large specimens have longer mandibles reaching 27 mm as total length of the body.

Description of female paratypes. – Body colour as described for the holotype male ( Fig. 2); mandible small, short, nearly triangular; outer edge bidentate, apical tooth acute and bends upwards, second tooth broadly rounded; clypeus longer than in males; anterior margin straight and strongly reflected; labrum not visible in dorsal view; antennal club as in the males; punctures on dorsal surface of head, pronotum and scutellum, much deeper and coarser than in males; setae and hairs on the whole body surface rather sparser than in males, on pronotum present only on the anterior-lateral sides; abdominal ventrites convex; abdominal ventrite 1 abbreviated medially, abdominal ventrites 2– 4 almost equal in length; posterior margin of abdominal ventrite 6 straight medially; protarsus smaller than in males; s tyli genitalis dorsal and ventral, respectively as in Fig. 5 and 6.

Relationships. – In general appearance, Didrepanephorus dangvani n. sp. is close to D. heterocolor Qiu, Zhao & Xu, 2021 , D. nishiyamai and D. subvittatus , a cluster of species characterized by the combination of the following characters: lower margin of male mandible with a distinctconcavity before basal tooth; pronotum evenly covered with untufted dense setae in male, with sparse short setae in female;abdominal ventrites with sparse setae; phallobase evenly curved in profile; parameres fused basally. The closest species appears to be D. heterocolor , described from China, Guizhou, of which the new species represent a southern vicariant. The two sister species are easily distinguishable by the different shape of paramera: see Fig. 7 - 8 and Fig. 35-36 in Qiu, Zhao & Xu (2021).

Distribution. Vietnam: Ha Giang and Lao Cai provinces. This new species is found only in the high mountain (> 1000 m) in the North of Vietnam with strongly seasonal climate while so than in the rest of the country prevail subtropical and tropicalclimate. Northern Vietnam present extensive karst formations, areas of irregular limestone eroded into towers, hills, caves and passages.