Onoreidium, Vaz-De-Mello, 2008

Vaz-De-Mello, Fernando Z., 2008, Synopsis of the new subtribe Scatimina (Coleoptera: Scarabaeidae: Scarabaeinae: Ateuchini), with descriptions of twelve new genera and review of Genieridium, new genus, Zootaxa 1955, pp. 1-75 : 37-39

10. Onoreidium , new genus

Diagnosis: Body oval ( Figs. 27–28). Head with clypeal teeth upturned and widely separated, emargination shallow and very widely U-shaped; clypeal margin with sides rounded (separately from gena) or straight, giving clypeus a trapezoidal shape. Head disc strongly convex with clypeofrontal suture at least weakly elevated and indicated laterally, frequently strongly carinated. Clypeal teeth separated by distance at least as wide as half interocular width, generally much more (Figs. 79, 82–83). Mesotibiae, in ventral view, with strong single tooth near middle of lateral border, with very strong short seta inserted apically; tibial ventral apical transverse margin interrupted by similar structures and without longer setae (Fig. 81). Pseudoepipleura gradually narrowed posteriorly ( Fig. 6), elytral discal interstriae with two rows of setose punctures.

Description: Length 3.5–5.5 mm. Body oval ( Figs. 27–28). Color grey to black, sometimes with strong metallic sheen. Clypeus with two very widely separated triangular, upturned teeth, emargination shallow. Clypeus rounded laterally (separately from gena) or straight, general clypeal form trapezoidal. Head disc strongly convex, clypeofrontal suture well indicated, carinate at least laterally. Clypeogenal suture indicated at least in front of each eye. Eyes, in dorsal view, elongated to oval, width half to fifth of eye length, interocular width seven to 14 times eye width (Figs. 79, 82–83). Pronotum covered by elongated setose punctures; lacking anterior and posterior beads; separated from hypomeron by very strong longitudinal carina. Hypomeron with strong lateral longitudinal carina, mesoepimera with strong anterior transverse carina; metasternal disc with setose punctures around middle. Elytra with flat interstriae, discal interstriae with biseriate punctures; striae deeper and wider apically. Pseudoepipleura with uniseriate setose punctures and additional scattered setose punctures on basal half. Protibiae with three teeth distributed along apical half or slightly less, without ventral scale-like setae. Protarsi with apical tarsomere modified to receive claws. All claws evenly curved, but with very sharp basal tooth. Mesotibiae (and metatibiae to lesser degree), in ventral view, with strong single tooth approximately at midlength of lateral border, with very strong short seta inserted apically, this tooth being similar to others interrupting ventral transverse apical carina of same tibia (Fig. 81). Mesotibiae and metatibiae very strongly expanded laterally very near apex, about 3.5 to four times as long as wide at apex. Parameres flattened apically (Fig. 80), shorter than half of phallobase length. Internal sac with very thick helicoidal pseudoflagellum. Coxites symmetrical, laminar, strongly toothed mesally. Spermatheca thin, C-shaped, gradually narrowed apically, rounded basally, with very long partially sclerotized duct.

Sexual dimorphism: Males possess an apically directed small apicomesal tooth in protibiae; concave metasternal disc (flat in females), flat shorter abdominal last sternite (longer and convex in females), and longer pygidium.

Type species: Trichillum cristatum Arrow, 1931 (present designation) = Onoreidium cristatum ( Arrow, 1931) , new combination.

Etymology: After Giovanni Onore, who kindly sent me specimens for study and is a great activist on the study of Latin American scarabaeoids. Gender neutral.

Distribution: Ecuador, northern Peru, and Panama, comprising the Arid Ecuador and Tumbes-Piura in the Northwerstern South American dominion, and Eastern Central America, in the Mesoamerican dominion, both in the Caribbean subregion. Cited from coastal Venezuela by Ferreira & Galileo (1993).

Remarks: Onoreidium has several apomorphies, such as, the unusual clypeal form, uniquely developed lateral mesotibial and metatibial tooth, thick pseudoflagellum, and convex head. It appears to be the sister genus of Pereiraidium , sharing with that genus the modified anterior tarsi in both males and females, strong tooth in claws, and same general head shape. This clade appears to be related to the Trichillidium-Bradypodidium clade (absence of ventral protibial scale-like setae, widely emarginated clypeus, strong lateral pronotal carina, and relative apical position of protibial tooth); however, it is not clear if that is a sister-group relationship, or if they form different grades of a paraphyletic group in relation to the remaining genera of Scatimina with fused abdominal sternites.

Composition: Besides the type species, the new genus contains O. ohausi ( Arrow, 1931) , new combination (described as Trichillum ), Onoreidium howdeni ( Ferreira & Galileo, 1993) , new combination, Onoreidium bottimeri ( Howden & Young, 1981) , new combination (described as Pedaridium ); and at least two new species are under study.

Material examined: