Eophileurus prelli Yang & Pathomwattananurak, 2022

Yang, Qiao-Zhi & Pathomwattananurak, Wuttipon, 2022, Four new species of the genus Eophileurus Arrow, 1908 (Coleoptera: Scarabaeidae Dynastinae) from Thailand and Vietnam, with notes on some Indochinese species, Zootaxa 5165 (4), pp. 451-485 : 470-472

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.”

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.

Figures

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.

FIGURES109–116.HabitusofEophileurusArrow,1908species(obliqueview).109–110,E.minorYang&Pathomwattananurak, new species, 109, holotype, 110, female paratype; 111–112, E. prelli Yang & Pathomwattananurak, new species, 111, male paratype; 112, female paratype; 113–114, E. quadratifovealis Yang & Pathomwattananurak, new species, 113, holotype, 114, paratype (Mu Si), 115–116, E. sidereus Yang & Pathomwattananurak, new species, 115, holotype, 116, female paratype.

FIGURES 165–184. Parameres of Eophileurus Arrow, 1908 species. 165–166, E. confinis Prell, 1913 (Bao Loc); 167–168, E. heyrovskyi Kral & Strnad, 1992 (Longli); 169–172, E. minor Yang & Pathomwattananurak, new species, 169–170, holotype, 171–172, paratype (Dong Tien, images ©Ming-Zhi Zhao); 173–174, E. prelli Yang & Pathomwattananurak, new species, holotype; 174–180, E. quadratifovealis Yang & Pathomwattananurak, new species, 175–176, holotype, 177–178, paratype (Mu Si), 179–180, paratype (Chatabon, images by Keita Matsumoto ©Natural History Museum, London); 181–184, E. sidereus Yang & Pathomwattananurak, new species, 181–182, holotype, 183–184, paratype; odd number ones, front view; even number ones, lateral view; scale bar = 2 mm.

FIGURES 65–70. Habitus of Eophileurus heyrovskyi Král & Strnad, 1992. 65–66, male (Mt. Laoshan); 67, male (Longli); 68–69, female (Luoyingou); 70, male (Luoyingou); 65, 67, 68, 70, dorsal view; 66, 69, ventral view.