Onthophagus turgidus Kohlmann & Solís, new species

Figs. 8, 14

Diagnosis. This species is distinguished from other species of the O. dicranius species group by the following combination of characters: body dark reddish brown (Fig. 8); clypeal horn upright, basal portion wide, forked in its apical third, apical portion nearly parallel-sided; pronotum broadly tumescent anteriorly (Fig. 8), apical portion of tumescence with well separated lateral tubercles; anterior pronotal apical bead angularly reflexed medially.

Description. Holotype. Male (Fig. 8): Length 10.3 mm. Humeral width 5.9 mm. Body oblong and dark brown. Vertex, pronotum, and elytral intervals closely punctate; vertex and pronotal punctures ocellate, surface between smooth; most elytral punctures with very minute setae.

Clypeus at anterior median edge with an upright, slightly arched, and flattened horn (Fig. 8); horn in its apical third bifurcate, Y-shaped, apical portion nearly parallel-sided (Fig. 8). Side of clypeus from rounded edge of gena to base of horn almost straight. Clypeal surface behind the horn concave. Frons surface feebly convex medially and with scattered punctures. Vertex with very small tubercle on each side near anterior inner edge of each eye; surface anterior to and between tubercles punctate, punctures between eyes ocellate.

Pronotum with anterior margin raised medially; anterior median half with large transverse tumosity (Fig. 8), delimited on each side by a distinct conical tubercle, tubercles evidently separated; anterior face of tumosity almost vertical with a small, slightly convex, tuberculated mid-line, tubercles very small. Pronotal surfaces near anterior lateral angles concave; marginal bead of posterior margin obsolete medially.

Elytron with striae distinctly impressed with ocellate punctures at regular intervals; intervals on disc with two or more irregular rows of punctures, surface between shiny. Pygidium closely ocellate-punctate, each puncture with a short stiff seta.

Metasternum with ocellate punctures, except along mid-line. Protibia elongate, with terminal tuft of setae; apical and subapical teeth distinctly closer to each other than second to third or third to fourth teeth. Ventral surface of all femora with regular, shallow punctures.

Examined material (1 specimen). Holotype, male: PANAMA. Panamá, Bocas del Toro. Fila a 1.5 km este de río Tskui, 800 m. 9.4453º N - 82.8471º W. Col: A. Solís y M. Moraga. Trampa 11. Proyecto Darwin.

Habitat. The specimen was collected with a trap baited with pig manure at an altitude of 800 m inside a primary tropical rain forest, during the month of October.

Geographical distribution (Fig. 14). This species is known so far from the Caribbean slope on the Panamanian Central Cordillera.

Chorological affinities. Onthophagus turgidus is found at similar altitudes in the Chiriquí Cordillera as O. solisi (500–1250 m; Kohlmann & Solís 2001; Fig. 9), its ecological equivalent (a small dung tunneller), in the Guanacaste and Tilarán Cordilleras.

Taxonomic relationships. More material is needed, especially females, in order to establish taxonomic relationships. Presently, and using the similar clypeal horn, the anterior pronotal marginal bead, and the pronotal tumescence, the new species would seem to be closely related to O. solisi Howden & Gill, and it might actually be its sister species.

This species will key to O. solisi in Kohlmann & Solís’ (2001) key. The male of the new species (Fig. 8) can be easily separated from the males of O. solisi (Fig. 9) by the form of the clypeal horn, which is thicker and more robust in the new species; as well as having a developed pronotal tumescence with more divergent lateral tubercles. With the description of these new species of Onthophagus in this paper, there are now 24 known from Panama.

Etymology. Turgidus, Latin adjective in the genitive case meaning swollen, in reference to the transverse pronotal tumosity.