Bothynus villiersi, Endrodi, 1968

Duarte, Paulo R. M., Grossi, Paschoal C. & Dupuis, Fabien, 2022, A taxonomic revision of the Bothynus villiersi Endrödi, 1968 species group (Coleoptera: Scarabaeidae: Dynastinae), Zootaxa 5093 (1), pp. 49-66 : 51-52

Bothynus villiersi species group

( Figs. 1A–D ; 2A–D ; 3A–E ; 4A–D ; 5A–D ; 6A–J ; 7A–D ; 8A–F ; 9 )

Composition. The Bothynus villiersi species group includes five species: Bothynus villiersi Endrödi, 1968 ; Bothynus horridus Endrödi, 1968 ; Bothynus alvarengai Martínez, 1983 ; Bothynus spinophallicus (Ratcliffe & Cave, 2021) ; and Bothynus belemensis Duarte, Grossi, & Dupuis , new species.

Diagnosis. The Bothynus villiersi species group has an exclusive set of characters within the genus: clypeus obliquely inclined downward in lateral view ( Fig. 1A ); frontoclypeal suture complete bearing a transverse ridge reaching the lateral margins of head ( Fig. 1B ); maxillary palpomere 1 short (three times shorter than palpomere 2) ( Fig. 1C ); labium with a conical process on disc in lateral view ( Fig. 1D ); parameres asymmetrical, provided of 1–2 process on inner lateral margins ( Fig. 6B, D, F, H, J ).

Description. The B. villiersi species group is characterized by oval-shaped species in dorsal view, convex dorsally in lateral view, ranging from reddish brown to dark reddish coloration. Head: Clypeus triangular, obliquely inclined downward in lateral view ( Fig. 1A ), with 2 raised tapered teeth on anterior margin; surface mostly transversely rugose, glabrous. Frontoclypeal suture with a raised, transverse, complete ridge that reaches the lateral margins of head ( Fig. 1B ). Frons glabrous, transversely rugose or rugopunctate except by a posterior smooth area. Ocular canthus subtriangular, transverse, with scarce setae scattered along of anterior margin. Mouthparts: Mandibles with 3 marginal teeth exposed laterally to clypeus; apical and medial teeth mostly triangular, basal tooth lobed. Maxillary galea shorter than lacinia, usually devoid of teeth, rarely provided with a small tooth on apex. Maxillary palpomere 1 short, about 2 times shorter than subsequent palpomere, hidden under lateral stipe ( Fig. 1C ); palpomere 4 clavate. Labium subtriangular, with a conical process on disc visible in lateral view ( Fig. 1D ), surrounded by scarce setae. Antennae: Comprised of 10 antennomeres; club oval, subequal in length to antennomeres 2–7 combined; lamellae 8–10 decreasing in size. Pronotum: Bearing a tubercle raised at middle of anterior margin; anterior middle area concave; posterior area strongly convex in lateral view. Elytra: Striae usually well marked; punctures ocellated, moderate to dense, irregularly scattered on interstriae; striae bearing punctures separated about 1–2 puncture diameters. Scutellar plate: Triangular, smooth. Legs: Protarsal claws strongly curved; protarsomere 5 elongate, subequal in length to tarsomeres 3–4 combined; protarsomeres 1–4 subequal in length. Protibia with 3 teeth on outer margin; margin slightly sinuous just behind the basal tooth. Meso- and metatarsomeres 1–4 decreasing gradually in size. Mesotibia usually with 2 weakly crenulate carinae on outer surface; basal carina short, transversely projected; medial carina long, obliquely projected; apex truncate; carinae and apex covered with stout spinule-like setae. Mesofemur subrectangular. Metatibia triangular, wide apically. Metafemur oval-shaped, wider compared to mesofemur. Venter: Prosternal process columnar, subcylindrical, raised between procoxae. Mesoventrite nearly completely rugopunctate, densely setose. Metaventrite coarsely rugopunctate, densely setose on sides, finely punctate and glabrous on disc. Abdomen: Tergite 7 with two paired rows of striae confined on discal area; striae well marked anteriorly, becoming finely marked posteriorly. Tergite 8 strongly convex lateral view; surface glabrous, rugose on sides and on a transverse area near to anterior margin, disc finely punctate. Aedeagus: Parameres asymmetrical, with 1–2 process on inner margins ( Figs. 6B, D, F, H, J ).

Sexual dimorphism. Females are similar to males, except by the pronotum weakly convex in lateral view, devoid of tubercle and concavity absent or shallow; tergite 8 flattened or weakly convex in lateral view, with an internalized plate on posterior margin ( Fig. 8C–F ); ventrite 6 triangular, complete on posterior margin and surface completely rugopunctate.

Figures

FIGURE 1. Morphological characters of the Bothynus villiersi species group: A, head in lateral view (mouthparts removed); B, head in frontal view; C, right maxilla in ventral view; D, head, prothoracic legs and pronotum in lateral view. Arrows indicate oblique downward clypeus in A, complete frontoclypeal ridge in B, palpomere 1 short in C, and conical process of mentum in D.

FIGURE 2. Holotype dorsal habitus with their respective labels on the right side: A, Bothynus villiersi Endrödi, 1968; B, Bothynus horridus Endrödi, 1968; C, Bothynus alvarengai Martínez, 1983; D, Bothynus spinophallicus (Ratcliffe & Cave, 2021).

FIGURE 3. Male dorsal habitus: A, Bothynus villiersi Endrödi, 1968; B, Bothynus horridus Endrödi, 1968; C, Bothynus alvarengai Martínez, 1983; D, Bothynus spinophallicus (Ratcliffe & Cave, 2021); E, Bothynus belemensis new species (holotype).

FIGURE 4. Pronotal tubercle: A, Bothynus alvarengai Martínez, 1983; B, Bothynus horridus Endrödi, 1968. Prosternal process: C, Bothynus villiersi Endrödi, 1968; D, Bothynus belemensis new species. Arrows indicate tubercle bilobed in A, tubercle conical in B, prosternal process apex conical in C, and prosternal process apex rounded in D.

FIGURE 5. Spiculum gastrale: A, Bothynus villiersi Endrödi, 1968; B, Bothynus horridus Endrödi, 1968; C, Bothynus alvarengai Martínez, 1983; D, Bothynus belemensis new species. hs = hemisternite.

FIGURE 6. Aedeagus in lateral view and parameres in dorsal view, respectively: A–B, Bothynus villiersi Endrödi, 1968; C–D, Bothynus horridus Endrödi, 1968; E–F, Bothynus alvarengai Martínez, 1983; G–H, Bothynus belemensis new species. lmp = left medial process, rbp = right basal process, rmp = right medial process. Arrow indicating elongated parameres apex in B.

FIGURE 7. Female dorsal habitus: A, Bothynus villiersi Endrödi, 1968; B, Bothynus horridus Endrödi, 1968; C, Bothynus alvarengai Martínez, 1983; D, Bothynus belemensis new species.

FIGURE 8. Female, detail of the anterior pronotal margin: A, Bothynus villiersi Endrödi, 1968; B, Bothynus belemensis new species. Female, internal view of the tergite 8: C, Bothynus villiersi Endrödi, 1968; D, Bothynus horridus Endrödi, 1968; E, Bothynus alvarengai Martínez, 1983; F, Bothynus belemensis. Arrows indicate arched margin in A, margin sinuous in B, and furrow in C. ip = internal plate.

FIGURE 9. Geographic distribution of the Bothynus villiersi species group. The star inscribed by a red circle indicates a possible mislabeled record.