Eophileurus vietnamensis Yang, Pathomwattananurak & Zhao, 2023

Yang, Qiao-Zhi, Geshev, Georgi, Pathomwattananurak, Wuttipon & Zhao, Ming-Zhi, 2023, Two new species of the genus Eophileurus Arrow, 1908 (Coleoptera: Scarabaeidae Dynastinae) from the Philippines and Vietnam, with first description of E quadratifovealis Yang & Pathomwattananurak, 2022 female, Zootaxa 5249 (2), pp. 290-300 : 295-298

Eophileurus vietnamensis Yang, Pathomwattananurak & Zhao , new species

( Figs. 4A–4H , 6A–6B )

Type material. (4♁♁, 5♀♀). Holotype: ♁ ( CAU), “ Pu Luong Nature Reserve , Ba Thuoc Dist., Thanh Hoa Prov., Vietnam, alt. 1200–1750 m, III.2022, local collector leg.” Paratypes: 1♀ ( CAU) “ Pu Luong Nature Reserve , Ba Thuoc Dist. , Thanh Hoa Prov., Vietnam, alt. 1200–1750 m, VI.2022, local collector leg.”; 1♁ ( CQZY), same label as the holotype; 2♁♁, 3♀♀ ( CQZY) “ Pu Luong Nature Reserve, Ba Thuoc Dist., Thanh Hoa Prov., Vietnam, alt. 1200–1750 m, VI.2022, local collector leg.”; 1♀ ( CQZY), “ Nghe An Prov., Vietnam, IV.2022, Van Dang leg.”

Holotype (male). General ( Figs. 4A–4C ): Body black, metasternum with slight reddish color, body shape oblong, flattened, surface shiny; ventral surface with sparse, short, reddish-yellow setae. Head: Clypeus sparsely punctate, with micropunctures on anterior region and larger punctures near sides; center with a long, slightly backward horn and a weak ridge from horn to apex; clypeal apex acute. Frons moderately depressed, disk with sparse micropunctures. Mandible sinuate on outer margin. Pronotum: Surface with dense punctures, punctures becoming denser and larger near all margins. Disc with a large, deep, round fovea; punctures in fovea dense and large, round or almost U-shaped; with 2 weak protuberances on each side. All margins beaded except before fovea, more strongly beaded at sides.Anterior angle protruding, apex rounded, posterior angle rounded. Scutellum: Surface with dense punctures on disc and sparse micropunctures near base. Elytra: Surface with sparse micropunctures, and dense and large, round punctures. Interstice 1 with punctures in 3 irregular rows combined to 2 irregular rows at middle then to 1 irregular row near posterior one-fourth, interstice 2 with punctures in 1 irregular row. Primary costa A distinct, primary costa B indistinct. Subapical umbone prominent. Lateral margin of elytron slightly curved outward, weakly and horizontally dilated from base to about posterior one-third. Pygidium: Surface convex, almost impunctate on disc, strongly rugopunctate near base and densely punctate on remaining area. Metasternum: Region near sides with dense and large punctures; median portion with sparse and small punctures; setae reddish-yellow, short, on anterior region excluding the middle, setae longer near base. Abdominal ventrites: Surfaces with sparse micropunctures throughout and larger punctures on each side; ventrite 5 and 6 each with a long, shallow horizontal depression at center. Legs: Protibia tridentate, protarsi moderately thickened, inner protibial claw strongly enlarged and moderately elongated. Inner metatibial spur long, slightly curved outward at middle; outer metatibial spur shorter, slightly curved outwards more strongly so than inner metatibial spur. Parameres ( Figs. 6A–6B ): Slender and symmetric; in frontal view ( Fig. 6A ), outer side prominent on basal one-third and at middle, then parallel at sides; inner margins parallel, with a small, acute and frontward process, then curved backward and outward, and then inward near apex; apex rounded, pointed inward; in lateral view ( Fig. 6B ), upper margin slightly depressed near base; inner processes invisible, outer prominent part downward, almost at right angle at its base; apex slightly bent backward.

Paratypes (male). Similarly or slightly less developed than the holotype; characters stable, the most underdeveloped male with differences as follow: clypeal horn shorter, clypeus more densely punctate, frons with rugopunctures near base; fovea smaller, almost longitudinally oval in shape, distinctly wider anteriorly, widest on anterior one-third; anterior margin of pronotum almost entirely beaded, with a small gap at middle; scutellum more sparsely punctate, with only a few punctures near base ( Fig. 4D–4E ).

Paratypes (female). Similar to male, but clypeus and frons densely rugopunctate throughout; clypeal horn shorter; fovea absent, with a shallow and densely punctate furrow on anterior region of pronotum, punctures in furrow distinctly larger and deeper than the others, round or nearly U-shape; anterior margin of pronotum entirely beaded; scutellum sparsely punctate near base; pygidium flattened from middle to base, with a clear protuberance between flattened area and apex, apex with a weak, flat and wide protuberance, punctures on pygidium denser on disc; ventrite 5 and 6 without depression, ventrite 6 with sparser punctures, rugopunctate near base; protarsi not thickened, inner claw not enlarged and elongated ( Fig. 4F–4H ).

Measurements. Length: male 22.0– 24.1 mm (holotype 24.1 mm), female 22.6–24.6 mm; width: male 10.3– 11.9 mm (holotype 11.9 mm), female 11.2–12.1 mm.

Diagnosis. The new species is closely allied to Eophileurus chinensis ( Faldermann, 1835) ( Figs. 5A–5F ) but can be distinguished by the following features: clypeus of similarly developed male usually slightly more densely punctate with slightly larger punctures; clypeus and frons of female usually with larger but shallower rugopunctures; fovea of well-developed males usually larger, more rounded; interstices 1 and 2 with denser punctures, row in interstice 2 irregular (usually regular in E. chinensis , rarely slightly irregular); elytral margin more weakly dilated; protuberance at apex of female pygidium indistinct, much smaller and wider (rather distinct and strong in E. chinensis ); outer margin of parameres parallel in apical half (diverging apicad toward the subapical curvature in E. chinensis ) with much wider gap between the inner process and the apex of paramere, inner process much smaller and sharper, not visible in lateral view (inner process large and somewhat rounded at apex, clearly visible in lateral view in E. chinensis , Figs. 6C–6D ).

Etymology. This species is named after its country of origin.

Distribution. Vietnam.

Figures

FIGURE 4. Habitus of Eophileurus vietnamensis Yang, Pathomwattananurak & Zhao, new species. A–C, holotype; D–E, male paratype; F–H, female paratype; A, D, F, dorsal view; B, G, ventral view; C, E, H, oblique view.

FIGURE 5. Habitus of Eophileurus chinensis (Faldermann, 1835). A–D, male; E–F, female; A, C–E, dorsal view; B, F, ventral view.

FIGURE 6. Male genitalia of Eophileurus species. A–B, E. vietnamensis Yang, Pathomwattananurak & Zhao, new species, holotype; C–D, E. chinensis (Faldermann, 1835); A, C, frontal view of parameres; B, D, lateral view of aedeagus.