Four new species of the genus Eophileurus Arrow, 1908 (Coleoptera: Scarabaeidae Dynastinae) from Thailand and Vietnam, with notes on some Indochinese species Author Yang, Qiao-Zhi 3 B, Pingguoshequ, Baiziwan Road, Chaoyang Dist., Beijing, 100022, P. R. China. Author Pathomwattananurak, Wuttipon 1051 / 38 Wiang, Mueang Dist., Chiang Rai Province, 57000, Thailand. text Zootaxa 2022 2022-07-18 5165 4 451 485 journal article 99517 10.11646/zootaxa.5165.4.1 cd84b880-d77f-401a-bf4c-a98021a5e166 1175-5326 6853942 DBE812FF-7B25-4522-97FE-45A86ECAEFD7 Eophileurus prelli Yang & Pathomwattananurak , new species ( Figs. 93–98 , 111–112 , 173–174 ) Type material. ( 2♂♂ , 3♀♀ ). Holotype : ( ♂ , MYNU ), “ 15°57'52.4"N , 107°26'20.6"E , Mt. Axan , Tay Giang Dist. , Quang Nam Prov. , Vietnam , alt. 1300 m , VIII.2017 , local collector leg.” Paratypes : 1♀ ( MYNU ) “ 15°57'52.4"N , 107°26'20.6"E , Mt. Axan , Tay Giang Dist. , Quang Nam Prov. , Vietnam , alt. 1300 m , XI.2017 , local collector leg.” ; 1♂ , 1♀ ( CYQZ ), “ 15°57'52.4"N , 107°26'20.6"E , Mt. Axan , Tay Giang Dist. , Quang Nam Prov. , Vietnam , alt. 1300 m , VII.2019 , local collector leg.” ; 1♀ ( CYQZ ) “ 15°57'52.4"N , 107°26'20.6"E , Mt. Axan , Tay Giang Dist. , Quang Nam Prov. , Vietnam , alt. 1300 m , VI .2020 , local collector leg.” FIGURES 93–98. Habitus of Eophileurus prelli Yang & Pathomwattananurak , new species . 93–94, holotype; 95, male paratype; 96–98, female paratypes; 93, 95, 96, 98 dorsal view; 94, 97, ventral view. Holotype (male). General ( Figs. 93–94 ): Body black, rather oblong, flattened, surface slightly shiny; ventral surface clads with dense, long reddish setae. Head: Clypeus sparsely punctate, punctures large, with a short, slightly backward horn at middle and a distinct ridge from horn to apex; clypeal apex slightly acute. Frons moderately depressed, disk with sparse micropunctures. Mandible sinuate at outer margin. Pronotum: Surface with dense, fine punctures, becoming much denser and larger near all margins. Anterior region with a large, rather deep, round fovea; punctures in fovea very dense and large, round or in sub-U-shape, sometimes coalescent mostly at anterior region; with two very weak protuberances at each side. All margins beaded except before fovea, more strongly beaded at sides. Anterior angle acute, posterior angle rounded. Scutellum: Surface impunctate. Elytra: Surface with sparse micropunctures, and dense and large, round punctures. Interstice 1 with punctures in two irregular rows combined at middle to one irregular row, interstice 2 with punctures in one irregular row. Primary costa A distinct, primary costa B indistinct. Subapical umbones moderately prominent. Margin of elytron slightly curved outward, dilated horizontally from base to about posterior three-seventh. Pygidium: convex, almost impunctate, except regions near all sides sparsely punctate. Metasternum: Surface mainly black, with slight reddish color at medial portion; with a lance-shaped depression at center; region near all sides with dense and small punctures; central portion with sparse and small punctures; setae reddish, long, mainly at anterior region. Abdominal ventrites: Surfaces with sparse micropunctures throughout and larger punctures at each side; ventrite 6 with a shallow, horizontally oval depression at center. Legs: Protibia tridentate, protarsi strongly thickened, inner protibial claw strongly enlarged and moderately elongated. Inner metatibial spur long, moderately curved outward at middle; outer metatibial spur shorter, strongly curved outwards. Parameres ( Figs. 173–174 ): Slender and symmetric; in frontal view ( Fig. 173 ), outer sides prominent at anterior one-third; inner margins sinuate, slightly curved outward between middle and apex; with a pair of processes emerging from inner margins near apex, apices curved forward, and a pair of processes at middle of outer margins, curved inward at apices; apex enlarged, outer margins extending outward; a pair of triangular processes from lower base of parameres visible; in lateral view ( Fig. 174 ), upper margin slightly depressed near base; outer processes bent backward; apex strongly bent backward. Paratype (male). Slightly underdeveloped than the holotype ; characters stable, with clypeal horn slightly shorter; fovea slightly smaller and shallower, in longitudinal oval shape, widest at anterior one-third; scutellum sparsely punctate, with only a few punctures near base ( Fig. 95 , 111 ). Paratypes (female). Similar to male, except clypeus and frons much more densely rugopunctate throughout; clypeal horn much shorter; fovea absent, with a very shallow and densely punctate furrow on anterior region of pronotum; scutellum sparsely punctate near base; pygidium flattened at middle; depression on metasternum shallower and slightly narrower; ventrite 6 without depression, with dense rugopunctures near anterior margin; protarsi not thickened, inner claw not enlarged and elongated ( Fig. 96–98 , 112 ). Measurements. Body length: male 22.9–23.5 mm ( holotype 22.9 mm ), female 23.5–25.4 mm ; body width: male 11.2–11.5 mm ( holotype 11.2 mm ), female 10.3–12.6 mm . Diagnosis. This species resembles E. heyrovskyi Král & Strnad, 1992 ( Figs. 65–70 ) due to the similar external characters and the backward processes at the outer sides of the parameres. It can be distinguished from the latter by the following points: elytral punctures relatively smaller; elytral margin more weakly dilated ( Figs. 93, 95–96, 98 ); metasternum with a lance-shaped depression at center ( Figs. 94, 97 ), whereas absent in E. heyrovskyi ( Figs. 66, 69 ); protarsi more strongly thickened ( Figs. 93–95 ); shapes of parameres different ( Figs. 167–168 for E. heyrovskyi , 173–174 for E. prelli , new species ). Etymology. This species is named in honor of the German zoologist Prof. Heinrich Prell (1888–1962) for his significant contribution to the study of the subfamily Dynastinae . Distribution. Vietnam . Remarks. Amongst other Eophileurus from Vietnam , E. prelli , new species is related to both E. heyrovskyi Král & Strnad, 1992 and E. baolocensis Muramoto, 2004 by the rounded posterior angle of pronotum. Although its type locality is closer to the distributing area of E. baolocensis , it is more closely related to E. heyrovskyi due to them both having backward processes on the outer sides of the parameres.Additionally, since its type locality is extremely close to Laos , occurrence of this species in Laos would not be surprising.