Aethina (Aethina) similinconspicua Chen & Huang, 2024

Chen, Xiaoxiao, Zhang, Jianhui & Huang, Min, 2024, New species and records of subgenus Aethina from China (Coleoptera: Nitidulidae), Zootaxa 5471 (1), pp. 141-147 : 142-143

Aethina (Aethina) similinconspicua Chen & Huang , sp. nov.

( Figs.1–9 )

Specimens examined. Holotype, ♂, China: Sichuan Province, Ganzi Tibetan Autonomous Prefecture, Moxi Town, 25-V-2023, Xiaoxiao Chen . Paratypes, 3♂♂ 2♀♀, same data as holotype, GSAU .

Diagnosis. This species can be distinguished from other species of the subgenus Aethina by: base of pronotum wider than base of elytra; scutellum transverse hemispherical; basal half of elytra red; median lobe with a small protrusion apically and a pair of crescent-shaped sclerite apically. This species is similar to A. (A.) inconspicua , but differs in the following: red base of elytra; golden-yellow pubescent; length of antennae significantly longer than head width; more prominent posterior angle of pronotum; anterior angles of median lobe is almost vertical; more slender gonocoxites and oblique gonostyli of female.

Description (male). Length 3.1–3.5 mm, width 2.2–2.6 mm. Body wide oval, strongly convex dorsally and ventrally. Dorsal and ventral surface black, basal half of elytra, pygidium, antennae, legs, and abdominal ventrite brownish red. Body surface with coarse punctures and densely golden pubescent ( Figs.1–2 ).

Head and pronotal surface with densely, rough elliptic or round punctures, punctures larger than eye facet, separated by at least 1.0× diameters, interspaces smooth. Elytral surface with rough, and small circular punctures arranged in insignificant rows, separated by at least 1.2–2.3× diameters, interspaces microreticular. Prosternum with rough, rounded punctures gradually spare toward margin. Mesoventrite smoothed. Metaventrite with nearly adjacent rough punctures. Abdominal ventrites 1–4 with moderately larger punctures than hypopygidium, punctures on abdominal ventrites 1–4 separated by 0.7–1.1 diameters, interspaces smooth, punctures on hypopygidium with 1.2–3.2 diameters apart, interspaces smooth.

Vertex flat. Clypeus deeply notched medially.Antennae shorter than head width (including eyes); scape swollen into triangle, pedicel slightly expanded, antennomere 3 obviously shorter than 4–5 combined; antennomere 4– 5 equal in length; antennomere 6–8 gradually thickened, antennomere 8 obviously disc-shaped; antennae club compacted, 0.4× total antennae length, terminal segment symmetrical apically, shorter than previous two segments combined. Pronotum truncated, length 2.4× width, widest basally and wider than base of elytra; anterior margin emarginate, posterior margin nearly straight, lateral margin gradually arched and sloped to ventral surface, anterior angles broadly obtuse and posterior angles projected. Scutellum laterally semicircular, length 0.4× basal width. Elytra nearly square, 2.4× longer than pronotum, lateral margins slightly constricted apically, shoulder angle not obvious and apical angles broadly rounded. Pygidium truncated apically and fully exposed.

Last segment of maxillary palpomere slender, cylindrical with constricted apex. Last segment of labial palpomere subulate with oblique truncate apex. Mentum pentagonal with a pointed tip. Antennal grooves deep, posterior margins distinctly convergent. Prosternum slightly carinate, prosternal process straight, slightly elongated beyond the base of procoxa, slightly widened near the top, and blunt apically. Mesoventrite strongly carinate, and posterior margin with a smooth depression. Metaventrite slightly depressed medially, and with a prominent mid-suture. First abdominal ventrite longest, followed in length by hypopygidium, and the 2 nd to 4 th segments of equal length. Distance between metacoxae 2× width of procoxae and mesocoxae.

All legs flat and stout. Protibia triangular and inner margin distinctly arched basally, outer apical angle broadly rounded. Mesotibia triangular with outer margins slightly arched basally, and outer apical angle with a distinct tooth. Metatibia elongated triangular, with inner and outer margins straight. All tarsi simple, strongly expanded, claws simple.

Male genitalia strong sclerotized. Tegmen rectangular with length 2.3× width, lateral margins parallel at basal half and gradually narrowing at apex. lateral pubescence extends from middle to the top ( Figs.3–4 ). Median lobe rectangular with length 1.9× width, with a small protrusion and a pair of crescent-shaped sclerite apically and a pair of long sclerite basally ( Fig.5 ). Ejaculatory rods short, and not fused to basal piece but fused each other at the base. Basal piece of internal sac sclerite nearly rectangular, slightly narrow apically ( Fig.7 ). The eighth abdominal sternite with lateral margins depressed, and bottom angle projecting upward ( Fig.6 ). Anal sclerite apex with elongated moderately dense fimbria ( Fig.8 ).

Female. Ovipositor moderate sclerotized. Paraprocts large with sclerotization along median line to basal lateral angles. Gonocoxites with sclerotized basal central and basal half, 2.5× length of gonocoxal extension. Gonocoxal apices round with well-developed oblique slender gonostyli apically ( Fig.9 ).

Biology and distribution. All specimens were collected in Southwestern China (Sichaun,) in May, host ranged from fresh to rotten flowers, including Hydrangea , Pittosporum and Rosaceae .

Etymology. The specific epithet is referring to the species similar to “ inconspicua ”.

Figures

FIGURES 1–16. A. (A.) similinconspicua sp. nov. (1) male habitus, dorsal, (2) male habitus, ventral; (3) tegmen, dorsal surface, (4) tegmen, lateral surface, (5) median lobe, dorsal, (6) male eighth abdominal sternite, dorsal, (7) internal sac sclerites of aedeagus, dorsal, (8) anal sclerite, dorsal, (9) ovipositor, dorsal; A. (A.) shizhuica sp. nov. (10) male habitus, dorsal, (11) male habitus, ventral, (12) median lobe, dorsal, (13) tegmen, lateral surface, (14) tegmen, dorsal surface, (15) anal sclerite, dorsal, (16) male eighth abdominal sternite, dorsal. Scale bars: 1mm (Scale bars: 0.2mm (1–2, 11–12), 0.2mm (3–9, 12–16).