Pocadius tenebrosus Chen & Huang, 2020

Chen, Xiaoxiao & Huang, Min, 2020, Two new species in the mycophagous genus Pocadius Erichson, 1843 from China (Coleoptera: Nitidulidae: Nitidulinae), Zootaxa 4802 (2), pp. 294-300 : 295-297

Pocadius tenebrosus Chen & Huang , sp. nov.

( Figs. 1–9 )

Specimens examined. Holotype, ♂: China: Yunnan Province, Dali City, Cangshan Mountain , 2580 m a.s.l., 25°40'24"N, 100°9'5"E, 15-VIII-2018, Xiaoxiao Chen ( NWAFU) . Paratypes, 13♂ 9♀: same collection data as holotype; Yunnan Province, Qujing City, Shizong County, Xiaofakuai Village , Junzi Mountain , habitat: Lycoperdon Pers : 1♂ 1♀: 19-VI-2016, Meike Liu ( NWAFU) , 2♂ 2♀: 14-VII-2017, 2♂ 1♀: 16-VII-2017, Xiaoxiao Chen and Ziyan Hui ( NWAFU) , 1♂ 3♀: 2059 m a.s.l., 24°39'42"N, 104°10'54"E, 15-VII-2017, Xiaoxiao Chen ( NWAFU) ; 1♀: Yun- nan Province, Qujing City , Xinping County, Yaonan Village , Ailao Mountain , 26-VI-2016, Meike Liu ( NWAFU) .

Diagnosis. Pocadius tenebrosus can be distinguished from other species of the genus Pocadius by a blackish dorsal surface; median lobe with V-shaped apex, prominent at lateral subapical angles; ejaculatory rods with swellings medially, sharply narrow and abutting apically, basal piece of internal sac sclerites with two robust paired sections and a central elongate piece, each with a pointed projection apically and basally. This species is similar to P. nobilis and P. yunnanensis , but differs from these two species by the following: elytra with decumbent and semi-erect setae; antennal club compact with terminal antennomere slightly longer than previous two antennomeres combined; tegmen with elongate, rectangular, shallow concavity in apical 0.4. The new species can be further distinguished from P. nobilis by the following: pronotum blackish with lateral margin light; elytra with smaller punctures; scutellar shield surface with dual punctation; tegmen with long setae apically; and from P. yunnanensis by: elytra with sparse punctures and puncture rows; mentum subtriangular; and tegmen with double rows of inner setae not attaining apex.

Description (male). Length 3.8 mm, width 2.2 mm. Body moderately convex, shiny. Dorsal surface blackish, ventral surface, lateral margins of pronotum, antennae and legs reddish-brown in holotype and most paratypes, except one paratype is reddish-brown dorsally with antennal club, disc of pronotum and lateral and anterior 1/2 of elytra and epipleura blackish. Pronotal and elytral margins with dense and elongate grayish fimbriae. Dorsal and ventral pubescence grey ( Figs. 1–2 ).

Head surface with deep punctures, vertex with dual punctation, larger punctures 2.5× diameter of smaller punctures, punctures becoming smaller at frontoclypeal region, large punctures 2.5× diameter of eye-facet, small punctures 1× diameter; interspaces smooth. Pronotal surface with dual punctation similar to that on head, interspaces smooth, 0.5–3.2 diameters apart. Scutellar shield surface with sparse large and small punctures, interspaces smooth. Elytral surface with longitudinal rows of large and small punctures in alternate arrangement, large punctures equal to large punctures on pronotum, separated by 1.1× diameter, giving rise to recumbent setae; small punctures 0.6× diameter of large punctures, separated by 2.5× diameter, giving rise to semi-erect setae; interspaces smooth to microreticulate; large and small puncture rows separated by 2.0× small puncture diameters. Pygidium with punctures same as punctures on vertex, interspaces granular. Mentum and submentum with large, sparse punctures, interspaces smooth to microreticulate. Prosternum with punctures similar to mentum, interspaces alutaceous. Mesoventrite with large, dense punctures at anterior margin, interspaces granular. Metaventrite in middle with punctures sparse and small, at sides with punctures sparse and large. Abdominal ventrite 1 with small, sparse punctures, interspaces smooth. Hypopygidium with large, dense punctures, interspaces alutaceous.

Head 2.5× as wide as long. Pronotum widest at base, width 2.3× length, anterior margin emarginate, posterior margin slightly undulate, lateral margins arcuate anteriorly. Scutellar shield subtriangular with round apex. Mentum subtriangular with broadly rounded apex. Prosternum carinate, prosternal process widening and bending toward mesoventrite posterior to procoxae, narrowing subapically. Mesoventrite carinate and extending to anterior 0.4 of mesocoxae. Metaventrite with width 2.5× length. Metanepisternum broad, axillary space 0.2× length of metanepisternum.Abdominal ventrite 1, 2.1× longer than ventrite 2; ventrites 2–4 subequal; hypopygidium equal to ventrite 1.

Antennal scape asymmetrical, slightly hemispherical, longer than pedicel; pedicel almost cylindrical; antennomeres 4 and 5 cylindrical; antennomeres 6–8 disc-like; antennal club compact, symmetrical, with terminal antennomere slightly longer than antennomeres 9–10 combined, club shorter than antennomeres 2–8 combined. Protibia with prominent apical process, longer than tarsomere 1; outer apical notch with ~150° angle; notch depth moderate, equal to length of tarsomere 1 and part of 2 combined; inner apical spine shorter than tarsomeres 1–2 combined. Meso- and metatibia with dense long setae and rows of slender spines on lateral edge. Mesotibia with apical process equal to protibial process, inner apical spine longer than tarsomeres 1–2 combined. Metatibia with apical process smaller than protibial process, inner apical spine shorter than tarsomere 1.

Male genitalia well-sclerotized. Anal sclerite with long fimbriae apically ( Fig. 7 ). Eighth abdominal ventrite with long apical fimbriae ( Fig. 9 ). Tegmen broadly rounded apically, length 1.8× width, lateral row of setae visible on posterior 3/5 to apex, inner row of setae not attaining apex, elongate, rectangular concavity in apical 0.4 ( Figs. 3–4 ). Median lobe with V-shaped apex and prominent angular lateral subapical angles, length 1.6× width, 0.8× length of tegmen ( Fig. 5 ). Internal sac sclerites as figured ( Fig. 6 ).

Female genitalia strongly sclerotized. Paraprocts large with sclerotization along median line to basolateral angles. Gonocoxites with sclerotized basal border, with a deep prominence and elongate baculi extending down median region, 0.4× length of gonocoxal extension. Gonocoxal apices with a recurved tooth possessing three long subapical setae ( Fig. 8 ).

Seasonality/Habitat. Specimens were collected from a species of the genus Lycoperdon in the subtropical plateau forest where Rhododendron grows during the summer in Yunnan Province, China.

Etymology. The specific epithet is derived from the Latin adjective “ tenebrosus ” indicating the dark color of the dorsal surface.

Figures

FIGURES 1–9. Pocadius tenebrosus sp. nov. (1) Male habitus, dorsal, (2) male habitus, ventral, (3) tegmen, dorsal, (4) tegmen, lateral, (5) median lobe, dorsal, (6) internal sac sclerites of aedeagus, (7) anal sclerite, (8) ovipositor, dorsal, (9) male eighth abdominal sternite, dorsal. Scale bars: A = 1 mm (1–2); B = 0.2 mm (3–5, 7–8), C = 0.2 mm (6, 9).