Onichodon rufus Otto, Muona and Córdoba-Alfaro, 2023

Otto, Robert L., Muona, Jyrki & Córdoba-Alfaro, Jim, 2023, A new genus and sixteen new species of false click beetles (Coleoptera: Eucnemidae) described from the Heredia Province of Costa Rica with several additional records from the Osa Peninsula and Panama, Insecta Mundi 2023 (991), pp. 1-36 : 17-18

Onichodon rufus Otto, Muona and Córdoba-Alfaro , new species

Figures 33–34

Diagnosis. The smaller size along with the reddish coloration with its habitus will distinguish the new species from O. confluentus new species and any other misplaced members of Fornax present in Costa Rica.

Type material. Female holotype: “ COSTA RICA: Heredia; pr: La Selva Bio. Sta.; 3 km S Pto. Viejo ; 10°26′N 84°01′W ” / “ 25.IV.1990; H.A. Hespenheide ” (“25”, “IV” and “0” handwritten on label) / “ HOLOTYPE:; Onichodon ; rufus ♀; Otto, Muona & Córdoba-Alfaro; Det. R. L. Otto; 2019” (red printed label). Holotype to be deposited in INBC.

Description. Female holotype: Length, 6.0 mm. Width, 1.5 mm. Body elongate; dark reddish; antennae and legs dark reddish; head, pronotum and elytra clothed with short, recumbent yellowish setae ( Figure 33 ). Head: Surface somewhat shiny, subspherical with crowded punctures; frons convex without carina or fovea; interantennal carina present; apical margin of frontoclypeal region weakly trilobed, more than 2 times wider than base; mandibles stout, bidentate, densely punctate. Antenna: Weakly serriform from flagellomeres I–IX, attaining about 1/3the length of the body, just beyond pronotal hind angle; flagellomere I longer than wide, longer than II; flagellomeres II–VIII each slightly longer than wide, sub-equal; flagellomere IX slightly longer than VIII. Pronotum: Surface somewhat shiny, with deep, crowded punctures; quadrate, with well-developed, sharp hind angles; sides parallel-sided at basal 2/3, arcuate at apical 1/3; disc convex, without carina or fovea; base sinuous. Scutellar shield: Slightly longer than wide, sub-triangular, shallowly punctate, setose and distally rounded. Elytra: Very shallow striae present; interstices slightly elevated; surfaces shiny, transversely rugose through much of the elytra. Legs: First tarsomere as long as the combined lengths of the remaining four on meso- and metatarsi; tibiae rounded in cross section; metatarsomeres I–III simple; metatarsomere IV excavated; metatarsomere V short with basally toothed claws. Venter ( Figure 34 ): Closely punctate, with short, recumbent yellowish colored setae; hypomeron with basally opened, lateral antennal grooves; metepisterna parallel-sided; elytral epipleura punctate; metacoxal plates medially 3.0–6.0 times wider than laterally.

Distribution. This eucnemid species is known from the holotype taken from La Selva within the province of Heredia.

Biology. No biological information is known for the new species. Larvae and pupae are unknown.

Etymology. The specific epithet is derived from its overall reddish coloration of its habitus.

Figures

Figures 31–34. Costa Rican macraulacine eucnemids. 31) Onichodon confluentus sp. nov., male holotype, ventral habitus. 32) Onichodon confluentus sp. nov., female allotype, dorsal habitus. 33) Onichodon rufus sp. nov., dorsal habitus. 34) Onichodon rufus sp. nov., ventral habitus. (Scale: 31–32 = 5.0 mm; 33–34 = 1.0 mm)