Euoniticellus intermedius (Reiche)

Edmonds, W. D., 2018, The dung beetle fauna of the Big Bend region of Texas (Coleoptera: Scarabaeidae: Scarabaeinae), Insecta Mundi 642, pp. 1-30 : 16

Euoniticellus intermedius (Reiche)

Fig. 60–63

Diagnosis. Dorsum mottled yellowish brown, usually with distinct dark, angular area extending along midline of pronotum. Pronotum evenly punctate; body elongate. Male ( Fig. 62–63 ) – Head with large, blunt, slightly curved, cylindrical horn (reduced to tubercle in small individuals); pronotum (seen in profile) enlarged and expanded toward head. Female ( Fig. 60–61 ) – Head with transverse, curved carina in front of and between eyes; pronotum flattened, rounded on sides. This species was re-described by Janssens (1953).

Big Bend collection sites (altitudinal range: 1055–1550 m [2490 m in Sierra El Carmen]). Brewster Co.: [1] ~ 17 km W Alpine ( Paisano Baptist Encampment ), 30°17′37″N 103°47′35″W, 1550 m (Jul) ; [2] * Elephant Mountain Wildlife Management Area , 30°03′04″N 103°32′56″W, 1345 m (Apr) .

Jeff Davis Co.: [1] Chihuahuan Desert Research Institute ( Quarry Unit ), 30°32′06″N 103°50′37″W, 1480 m (Sep).

Presidio Co.: [1] ~ 96 km SSE Marfa ( Old Alazan Ranch , headquarters), 29°33′01″N 103°53′25″W, 1275 m (Mar) ; [2] 37 km SSW Marfa (along FM 2810 , Petan Ranch – Cherry Hills sector), 30°07′35″N 104°19′24″W, 1630 m (Jun) ; [3] ~ 6 km W Marfa (Hip-O Ranch), 30°21′54″N 104° 7′12″W, 1530 m (Aug– Sep) ; [4] 60 km SSE Marfa (along FM 169 ), Casa Piedra , 29°44′07″N 104°03′03″W, 1055 m (Sep) .

MEXICO: Coahuila, Sierra El Carmen, Maderas del Carmen , 29°00′06″ N 102°35′48″ W, 2490 m [Jul].

Collection method(s). a) baited pitfall trap (human feces); b) direct capture (cow dung; horse dung).

Surface activity. Diurnal.

Habitat. Generally distributed throughout the region in all habitats, although more common in open pasturelands in association with livestock.

Comments. This species spends its life in a dung pad and, because it is often dirtied by adhered fragments of dried dung and has the habit of feigning death (thanatosis) when disturbed, it is splendidly camouflaged. It is common in the Big Bend, but I have never observed population levels to even closely approximate those of D. gazella . The efficacy of the activities by E. intermedius in the control of nematodes is discussed by Martínez et al. (2018).

Figures

Figures 60–69. Euoniticellus and Copris. 60) E. intermedius, dorsal view, female. 61) Same, lateral view of forebody. 62) Same, dorsal view, male. 63) Same, lateral view of forebody. 64) C. arizonensis, dorsal view of forebody, large male (southwestern Arizona). 65) Same, dorsal view, small male (Big Bend). 66) Same, lateral view of forebody. 67) Same, lateral view of forebody, female. 68) Same, oblique dorsal view. 69) Same, dorsal view of head and prothoracic margin.