Bothynus ascanius
Creators: name: Duarte, Paulo R. M.
name: Dupuis, Fabien
name: Grossi, Paschoal C.
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Scarabaeidae
Bothynus
Bothynus ascanius

description: Identification key to the species of the Bothynus ascanius species group
Note: the key only permits the identification of physically complete and unworn specimens. Unfortunately, incomplete or abraded specimens may be impossible to identify when the requisite characters are missing.
1. Surface of elytra glabrous (Fig. 10 (a, b)) ....................................................................................... 2
- Surface of elytra bearing conspicuous yellowish setae (Fig. 10 (c)). Argentina, Bolivia and Brazil ............................................................................................................ Bothynus trix Hardy
2. Elytral epipleura with distinct and complete margin (Fig. 10 (e)) ....................................... 3
- Elytral epipleura either lacking margin, or with incomplete margin when present (Fig. 10 (d))................................................ ................................................ Bothynus arriagadae sp. n.
3. Surface of elytra bearing deep, well-impressed punctures, ranging in size from small to large (Fig. 10 (b)) .................................................................................................................................. 4
- Surface of elytra nearly smooth, with only minute or shallow, poorly-impressed punctures (Fig. 10 (a)). Argentina, Bolivia, Brazil and Paraguay ................................................ .............................................................................................................. Bothynus laevipennis Arrow
4. Outer mandibular teeth distinctly separated from each other by deep interval in dorsal view (Fig. 5 (b, d, e))................................................................................................................................ 5
- Outer mandibular teeth nearly fused with each other, separated only by a shallow interval in dorsal view (Fig. 5 (c)). Argentina and Paraguay ...................................... ................................................................................................................... Bothynus minor Steinheil
5. Apical tooth of mandible acuminate or narrowly rounded at apex, in dorsal view (Fig. 5 (b, d))........................................................................................................................................................ 6
- Apical tooth of mandible diagonally truncated apex (Figs. 5 (d))..................................... 10
6. Medial tooth of mandible posteriorly produced or forming a right angle with the plane of mandibular orientation in lateral view (Fig. 5 (f)).................................................................. 7
- Medial tooth of mandible anteriorly produced at an oblique angle to the plane of mandibular orientation in lateral view (Fig. 5 (g)) ...................................................................... 8
7. Protarsomere 5 of male abruptly expanding toward apex (Fig. 11 (b)); tergite 8 of female covered by strong rugopunctures on disc (Fig. 20 (a)). Argentina, Brazil, and Paraguay .................................................................................... Bothynus cyclops (Burmeister)
- Protarsomere 5 of male gradually expanding toward apex (Fig. 11 (i)); tergite 8 of female with fine punctures on disc (Fig. 20 (b)). Argentina, Brazil and Paraguay ..... ...................................................................................................................... Bothynus gisae sp. n.
8. Outer apex of metatarsomere 1 lacking angular projection (Fig. 18 (e)); sides of tergite 8 with distinct cavity in female (Fig. 20 (d)).................................................................................. 9
- Outer apex of metatarsomere 1 with long angular projection (Fig. 18 (d)); sides of tergite 8 flattened in female, lacking distinct cavity (Fig. 19 (c)). Argentina, Brazil and Paraguay. .............................................................................. Bothynus deiphobus (Burmeister)
9. Clypeus glabrous or bearing a few small setae in both sexes (Fig. 5 (e)); sternite 8 of female with glabrous disc (Fig. 21 (d)). Argentina, Bolivia, Brazil, Paraguay and Uruguay ............................................................................................................... Bothynus fabius (Fairmaire)
- Clypeus bearing moderately dense yellowish setae (Fig. 5 (a)); sternite 8 of female with setose disc (Fig. 21 (a)). Male unknown. Argentina ............ ............ Bothynus bentoi sp. n.
10. Teeth of anterior clypeal margin each bearing a longitudinal carina (Fig. 6 (d, f)). 11
- Teeth of anterior clypeal margin lacking longitudinal carinae (Fig. 6 (b)).................. 12
11. Inner protarsal claw lacking incision; Pronotum with a broad and distinctly deep cavity (Fig. 17 (e)). Male unknown. Brazil .................. .................. Bothynus moroni sp. n.
- Inner protarsal claw of male incised (such in the Fig. 11 (a)); pronotal cavity shallow in female (Fig. 17 (k))............................. ............................. Bothynus scutellopunctatus sp. n.
12. Pronotal cavity rounded in shaped in both sexes, usually small, shallow and confined to the anterior region (Fig. 8 (b)), if broad and deep, then not transversely produced (Fig. 8 (a)); usually small to medium sized species, rarely attaining 30.0 mm in length.............................................................................................................. 13
- Pronotal cavity oval in shape in both sexes, deep, broad and transverse (Fig. 8 (c, d)); larger species, from 31.5 to 34.5 mm in length................................................................... 19
13. Dorsal surface distinctly shining, not opaque; ventral surface of the metafemur with glabrous disc in both sexes (Fig. 18 (a, c)).............................................................................. 14. Dorsal surface with opaque aspect, not distinctly shining in both sexes; ventral surface of the metafemur entirely covered by setae in both sexes (Fig. 18 (b)). Brazil .................................................................................................... Bothynus cribrarius (Fairmaire)
14. Dorsal surface of body with reddish brown or dark reddish color; interocular width about 3.8–4.5X transverse diameter of eye; maxilla bearing three teeth (subequal or not) arranged on the apex of galea (Fig. 7 (b, d))................................................................ 15
- Dorsal surface of body with dark color (Figs. 3 (l), 16(b)); interocular width about 5.3– 5.4X transverse eye diameter; maxilla bearing five asymmetric teeth arranged on the apex of galea (Fig. 7 (c)). Argentina and Paraguay ....... ....... Bothynus ovalatus sp. n.
15. Punctures on the posterior sides of male pronotum small to large in size, either contiguous or separated by three puncture diameters (Fig. 9 (c, d, g, k, l)); tergite 8 of female glabrous (Fig. 20 (i, l)) or if setose, pronotum with conical tubercle and deep concavity (Fig. 17 (i))........................................................................................................................ 16
- Punctures on the posterior sides of male pronotum minute (Fig. 9 (a, b)); pronotal concavity of female shallow (Fig. 17 (a)); tergite 8 densely setose (Fig. 19 (e))................ ............................................................................................................... Bothynus ascanius (Kirby)
16. Male pronotum with a small and gibbose anterior tubercle (Fig. 9 (c, g)); female with sternites 4–8 glabrous or weakly setose on discal region (Fig. 21 (b)) ....................... 17
- Tubercle of male pronotum conical and acuminate at apex (Fig. 9 (k)); female with sternites 4–8 having dense setae on discal region (Fig. 21 (c)). Argentina ....................... ................................................................................................................ Bothynus rufipennis sp. n.
17. Pronotal cavity with posterior margin complete or with an indistinct interruption in both sexes (Fig. 9 (g))...................................................................................................................... 18. Pronotal cavity with posterior margin distinctly interrupted at middle in both sexes (Fig. 9 (c)). Argentina, Brazil and Paraguay ............ ............ Bothynus cylindricus Arrow
18. Inner protarsal claw of male with outer branch clearly shorter than inner one (Fig. 11 (e, f)); tergite 8 of female with discal area covered by shallow and transverse punctures (Fig. 20 (c)). Argentina and Brazil ........ ........ Bothynus laticifex Burmeister Inner protarsal claw of male with outer branch subequal in length to inner one (Fig. 11 (k)); tergite 8 of female with densely rugopunctate discal region (Fig. 20 (e)). Paraguay .......................................................................................................................... Bothynus sapukai sp. n.
19. Protasomere 5 of male with a ventroapical process (Fig. 11 (j)). Female unknown....... .................................................................................................................. Bothynus robustus sp. n.
- Protarsomere 5 of male without ventroapical process (such as in the Fig. 11 (h)); female with a transverse tubercle on posterior margin of pronotal cavity (Fig. 17 (g)). Bolivia ....................................................................................................................... Bothynus nyx Ratcliffe
description: Published as part of Duarte, Paulo R. M., Dupuis, Fabien & Grossi, Paschoal C., 2025, Taxonomic revision of the Bothynus ascanius (Kirby, 1819) (Coleoptera: Melolonthidae: Dynastinae) species group, pp. 663-737 in Journal of Natural History 59 (9 - 12) on pages 732-735, DOI: 10.1080/00222933.2025.2456579, http://zenodo.org/record/14971553