Enanea baba, Wang, 2021

Wang, Cheng-Bin, 2021, First record of the genus Enanea Lewis from the Chinese Mainland, with description of a new species (Coleoptera: Tenebrionidae: Diaperinae), Zootaxa 5032 (1), pp. 80-86 : 81-85

Enanea baba sp. n.

Figs. 1A–F ; 2A–D ; 3A–D

Holotype: ♂, China, Yunnan: Nujiang Prefecture, Gongshan County, Dulongjiang Township [DAE江乡], 1800– 2000 m, 19.III.2021, Bai-Jun Li leg. ( MYNU).

Description. Body 4.8 mm in length, 2.1 times as long as wide, widest around basal 1/3 of elytra. Lengths of body parts (mm): head (0.5), eye (0.2), antenna (1.3), pronotum (1.2), elytra (3.1); width: head (1.3), eye (0.1), pronotum (2.2), elytra (2.3).

Habitus ( Figs. 1A–F ). Body oblong, robust, moderately convex above and shiny. Color mostly reddish brown; eyes yellowish; mouthparts (except apices and outer sides of mandibles blackish), antennae, lateral margins of pronotum, and legs yellowish brown. Dorsal surface almost glabrous, ventral surface sporadically and finely setose. Antennae and legs covered with yellow setae, which are somewhat denser on apical six antennomeres, apico-mesial areas of tibiae and ventral sides of tarsi.

Head ( Figs. 1A–F ) subhexagonal, 2.6 times as wide as long, widest at eyes, nearly parallel-sided posteriorly. Clypeus ( Figs. 1A, E, F ) transversely subhexagonal, 3.9 times as wide as long, margined anteriorly, widely and weakly emarginate at anterior margin and weakly upturned at rounded apico-lateral corners; surface slightly concave, sparsely scattered with fine punctures. Fronto-clypeal suture fine, feebly impressed. Genae bearing a pair of long, strong, thick, erect horns, which are slightly oblique outward and forward; penniform, wide and straight, not curved backward in lateral view ( Fig. 1C ). Frons moderately concave between horns, distinctly and sparsely punctate. Eyes small, weakly produced, devoid of inner ocular sulci; elliptical in lateral view ( Fig. 1C ), 1.5 times as long as wide. Gula ( Fig. 1D ) triangular; gular suture clear but not sulcate.

Mouthparts. Labrum (Figs. E, F) semicircular, microreticulate, with short yellow setae dorsally. Mandibles ( Fig. 1D ) with subacute apical tooth, and a small tooth at subapex of lower edge of mesial side. Maxillary palpi ( Fig. 1D ) with terminal palpomere securiform. Labial palpi ( Fig. 1D ) with terminal palpomere elongated conical. Mentum ( Fig. 1D ) subtrapezoidal, weakly convex in central and with a distinct central tubercle. Submental peduncle ( Fig. 1D ) almost smooth, bearing several setigerous punctures. Anterior part of gulamentum strongly and transversely depressed behind submental peduncle.

Antennae ( Figs. 1A, D, E, F ) short, robust, strongly flattened, 1/4 length of body and as long as head width; each antennomere without stalk. Proportion of antennomeres from base to apex in μm (length × width): scape (208 × 141), pedicel (97 × 109), III (113 × 109), IV (111 × 120), V (104 × 137), VI (107 × 186), VII (116 × 258), VIII (125 × 286), IX (141 × 282), X (191 × 257). Scape ovate, robust, 1.5 times as long as wide; subcylindrical from pedicel to antennomere V, gradually dilating; III as long as IV and as wide as pedicel; V 1.3 times as wide as long; VI moderately dilated; VII–IX cyathiform, strongly dilated; X transversely ovate; apical four antennomeres forming an oblong club, 0.8 times shorter than basal six.

Pronotum ( Figs. 1A–C, E, F ) subtrapezoidal, 1.8 times as wide as long, widest at middle. Apical margin widely and shallowly emarginate, slightly produced in medial half, finely grooved and rimmed; basal margin almost straight, wholly and finely grooved and rimmed; lateral margins evenly arcuate, expansively grooved and finely rimmed, the rim irregularly and sparsely serrate by setigerous fine punctures. Front angles obtusely rounded, slightly upturned and weakly produced; hind angles subrectangular, not rounded. Dorsum moderately convex, densely covered with distinct, small, round punctures, which are somewhat smaller than those on frons.

Scutellum ( Figs. 1A, B ) transversely linguiform, narrowly rounded at apex. Surface densely and minutely punctate in central area.

Elytra ( Figs. 1A–C, E ) oval, 1.3 times as long as wide, widest around basal 1/3, 2.6 times as long as and almost as wide as pronotum. Lateral margins gradually widening from humeri to basal 1/3, then gradually narrowing to rounded apices; moderately grooved and finely rimmed, the rim irregularly and sparsely serrate by setigerous fine punctures, serrations more obvious and sharper than those on pronotum. Dorsum moderately convex though almost flattened in basal half; each elytron with eight irregular rows of close and coarse punctures, and a scutellary striole of fine and sparse punctures along suture; intervals faintly convex, sparsely scattered with punctures smaller than those in rows. Epipleura ( Fig. 1D ) uneven, wide at base, narrowing toward apex and terminated between abdominal sternites VI and VII, and sparsely and finely punctate. Wings fully developed.

Legs ( Figs. 1A–F ) short. Femora dilated; meso- and metafemora more or less clavate. Tibiae straight, dilated apically; protibia with ecto-apical angle obtusely angulate, not produced. Tarsi stout.

Ventral side ( Fig. 1D ) feebly convex. Prosternum sparsely scattered with small punctures; prosternal process narrow and slightly elevated between coxae, triangularly divergent posteriorly, with a small tubercle at middle of apex. Mesoventrite sunken, densely covered with coarse punctures. Metaventrite weakly convex toward middle, finely grooved medially, with punctures sparse and coarse, becoming denser laterally. Metanepisternum densely punctate.

Abdomen. Abdominal tergite VII ( Fig. 3A ) semicircular, widely rounded at posterior margin, sclerotized in V shape at disc as well as along posterior margin, and sparsely covered with short setae on dorsal surface; tergite VIII ( Fig. 3B ) semicircular, subtriangularly membranous in about basal 2/3, and sparsely covered with long setae along posterior margin. Abdominal ventrites densely and finely punctate; sternite VII ( Fig. 2A ) subtriangular, rounded at posterior margin; sternite VIII ( Fig. 3C ) subhexagonal, widely and distinctly emarginate at posterior margin, sclero- tized in apical half where the surface is densely covered with long setae. Abdominal segment IX as shown in Fig. 3D , with subgenital plate broadly rounded at anteroventral margin, without median strut; tergite IX divided into two separated laterotergites which rounded at posterior margins.

Aedeagus ( Figs. 2B–D ) slender, simple, 0.54 mm in length and 0.12 mm in width. Basale subovate, 0.26 mm in length, widest at about basal 2/5; weakly curved in lateral view ( Fig. 2D ). Apicale elongate subtriangular, nearly parallel-sided in basal 2/5, thickened at apex, 0.28 mm in length, 1.1 times as long as basale; thick, obliquely straight in lateral view ( Fig. 2D ).

Female. Unknown.

Etymology. The specific epithet is from the Chinese Pinyin “bà ba [爸爸]”, which means father. It is dedicated to Pei-Liang Wang [Ɨü良] (Chengdu, China), tHE father of the author. The name is a noun in apposition.

Biology. According to the recollection of the collector, the holotype was collected from wettish rotten wood (like the recently described species Micropeneta qilin Li & Jiang, 2019 from related genus).

Distribution. China (Yunnan).

Differential diagnosis. Enanea baba sp. n. is distinguishable from other congeneric species by the combination of the following characters: clypeus widely and weakly emarginate at anterior margin ( Figs. 1A, E, F ); genal horns long, strong, thick, erect, and penniform, wide, straight, not curved backward in lateral view ( Figs. 1A–C, E, F ); antennae with apical four antennomeres forming an oblong club ( Figs. 1A, D ); pronotum with apical margin widely and shallowly emarginate, slightly produced in medial half ( Figs. 1A–B ); front angles obtusely rounded, slightly upturned and weakly produced ( Figs. 1A–B ); hind angles subrectangular, not rounded ( Figs. 1A–B ); protibia with ecto-apical angle obtusely angulate, not produced ( Figs. 1A, D ); male genitalia with apicale elongate subtriangular, nearly parallel-sided in basal 2/5, with apex thickened, and thick, obliquely straight in lateral view ( Figs. 2B–D ).

Figures

FIGURES 1A–F Habitus of Enanea baba sp. n., holotype, ♂. (A dorsal view; B dorsolateral view; C lateral view; D ventral view; E oblique view; F frontal view)

FIGURES 2A–D Enanea baba sp. n., holotype, ♂: A abdomen; B–D aedeagus. (A, B ventral view; C dorsal view; D lateral view)

FIGURES 3A–D Enanea baba sp. n., holotype, ♂: A tergites VI+VII; B tergite VIII; C sternite VIII; D abdominal segment IX. (A, B dorsal view; C, D ventral view)