Epironastes Carne, 1957

Hutchinson, Paul M. & Allsopp, Peter G., 2020, Revision of Epironastes Carne, 1957 (Coleoptera: Scarabaeidae: Dynastinae Pentodontini: Pseudoryctina) with description of the female, behaviours, and habitats, Zootaxa 4852 (4), pp. 428-448 : 429-430

Epironastes Carne, 1957

Epironastes Carne, 1957: 124 , Figs. 322–333; Endrődi 1985: 382, Figs. 1395–1397; Cassis & Weir 1992: 400; Dechambre 2005: 67; Krajcik 2005: 42; Krajcik 2012: 103; Weir et.al. 2019: 524, Plate 54O.

Apironastes: Endrődi 1974: 38, Figs. 48–50 (misspelling).

Type species. Epironastes nigrisetosus Carne, 1957 , by original designation.

Redescription. Body dorsally dark brown-black, ventral surface brown or black, 9.7–21.7 mm long (apex of clypeus to tip of pygidium), 6.0– 12.6 mm wide (widest at midlength of elytra). Mentum broad at base, slightly narrowed to ligula; ligula slightly or strongly reflexed, rounded or weakly bilobed; maxillae reduced to small subtriangular pieces with irregular inner margins; palps short, palpomere 4 cylindrical; mandibles exposed, evenly rounded; labrum concealed. Antenna with 10 antennomeres, club longer than shaft, scape and pedicel setose. Clypeus strongly narrowed, upturned at apex, weakly emarginate, deflexed across ridge joining antennal angles anterior to clypeofrontal suture; clypeofrontal suture usually obliterated, transverse, in middle weakly posteriorly arcuate. Frons rugulose; ocular canthi broad, coarsely punctate, surpassing outline of eye. Pronotum with anterior margin membranous, disc conspicuously punctate, basal ridge continuous, widest in apical half, basolateral angles well defined. Each elytron with sutural stria punctate or linear-punctate, punctures of disc simple or annulate, surface often microreticulate, epipleurae poorly developed, lateral setae extending posteriorly as far as first abdominal sternite. Postcoxal prosternal process apically tapering posteriorly or truncate, densely setose. Pygidium weakly or strongly convex, mostly setose across base, apical ridge mostly glabrous. Abdominal sternites setose, sternite 5 glabrous across middle; coxae with abundant yellow, orange or black vestiture. Protibiae tridentate, tarsomeres 1 and 5 subequal in length; metafemora moderately stout bearing a single sulcus; metatibiae dilated at apex, bicarinate, distal cilia short, stout and closely set, spurs usually broad, subparallel or subspatulate, not or only weakly curved; metatarsomeres slender, tarsomere 1 not dilated, equal to or longer than tarsomere 5.

Male. Pronotum with anteromedian tubercle in front of an impression that is either confined to anterior half or continued over basal convexity by shallow impression. Antennal club subequal to or slightly longer than shaft, straight, elongate oval, setose on inner surface. Genitalia with phallobase short, broad, parameres narrow basally, usually laterally abruptly dilated in apical half, either with arcuate margin to apex or with pre-apical lateral process.

Female. Pronotum with anteromedian tubercle obsolete, impression as small, flattened region. Antennal club shorter than shaft. Abdominal sternites setose across middle. Metatarsomeres stout, shorter than tibial length, tarsomere 1 slightly broadened.

Differential diagnosis. Epironastes shares with Teinogenys Sharp, 1873 a broad, strongly compressed, and reflexed mentum; large exposed mandibles; and small maxillary palps. The two genera are at once distinguished by the upturned clypeus in Epironastes , and the presence in this genus of an anteromedian pronotal tubercle. The shape of the clypeus ( Figs. 7 , 15 , 25 , 36 , 47 ) separates Epironastes from all other Pseudoryctina . It is deflexed ventrad, either evenly curved or abruptly declivous, not from the clypeofrontal suture, but from a ridge joining the antennal angles, and is narrowed distally, the sides sinuate to a very narrow anterior face that is distinctly upturned. In this, and in some other characters, Epironastes looks similar to species of Semanopterus Hope, 1847 , but Epironastes species have sexually dimorphic antennae and an upturned clypeus. The keys of Carne (1957) and Weir et al. (2019) will separate the genera of Australian Pseudoryctina .

Figures

FIGURES 43–50. Epironastes nigrisetosus Carne, 1957, male, Dempster Inlet specimen. 43, dorsum; 44, venter; 45, lateral; 46, head, lateral; 47, head, dorsal; 48, pygidium; 49, parameres; 50, aedeagus, lateral.

FIGURES 3–10. Epironastes abruptus Carne, 1957, male specimen #0465. 3, dorsum; 4, venter; 5, lateral; 6, head, lateral; 7, head, dorsal; 8, pygidium; 9, parameres; 10, aedeagus, lateral.

FIGURES 11–16. Epironastes abruptus Carne, 1957, female specimen #0464. 11, dorsum; 12, venter; 13, lateral; 14, head, lateral; 15, head, dorsal; 16, head and pronotum, frontal.

FIGURES 21–28. Epironastes demarzi (Endrődi 1971), male specimen #1713. 21, dorsum; 22, venter; 23, lateral; 24, head, lateral; 25, head, dorsal; 26, pygidium; 27, parameres; 28, aedeagus, lateral.

FIGURES 32–39. Epironastes limbatus Carne, 1957, male specimen #1703; 32, dorsum; 33, venter; 34, lateral; 35, head, lateral; 36, head, dorsal; 37, pygidium; 38, parameres; 39, aedeagus, lateral.