Canthon inusitatus Kohlmann & Solís, 2006

Kohlmann, Bert & Solís, Ángel, 2006, New species of dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae) from Mexico and Costa Rica, Zootaxa 1302, pp. 61-68 : 65-68

Canthon inusitatus Kohlmann & Solís , sp. nov. ( Figs. 4, 5 )

Diagnosis. This species is distinguished by the following combination of characters: body oval, convex, black; dorsal surface shagreened; legs dark brown with a reddish hue. Posterior border of head clearly margined; second labial palpomere smaller than first; mentum entire; thorax strongly transverse; elytra not carinate; meso­ and metatibiae lacking transverse carinae; meso­ and metatarsomeres narrow and elongate, distal four tarsomeres as a group parallel­sided or nearly so, first tarsomere very small, its length about half that of second; metatibial spur spinose and sharp.

Description of holotype. Male. Length: 7.9 mm, humeral width: 5.9 mm. Body oval and convex, completely black; dorsal surface shagreened.

Head with surface smooth, with fine punctures; posterior border of head clearly margined, margin with punctation at regular intervals; antenna brown, club grayish­brown. Clypeus anteriorly bidentate ( Fig. 4), with a V­shaped emargination between teeth. Eyes small, dorsally only 7 facets wide and approximately twice as long as wide, separated by approximately 36 times their dorsal width ( Fig. 4).

Thorax much wider than long ( Fig. 4); anterior angles well developed and acute; lateral borders forming angled arch; posterior angles poorly defined; anterior and lateral borders margined; disc very convex, finely punctured; without evident prescutellar impression. Prosternum with proepimeral carina absent.

Elytra with striae nearly obsolete and finely punctate; interstriae shagreened, finely punctate, convex.

Pygidium large (3.5 mm width versus 3.6 mm head width) and triangular; base not margined; disc convex, finely punctate.

Protibia with three teeth on external edge, the apical tooth broadened towards apex with slender, acute apical spur ( Fig. 4); ventral surface of metafemur lacking lines adjacent to posterior margin; metatibia slender and curved; meso­ and metatarsi long and slender, first tarsal article clearly shorter than second ( Fig. 4); basal one­third of metafemur slender.

Female. Unknown.

Material examined (1 specimen). Holotype male: COSTA RICA. Heredia. 6 km ENE Vara Blanca, 2000 m, 13 abril 2002, 20/TF/05, D. Brenes, M. Paniagua y R. Vargas. Habitat. The species was collected in cloud forest (lower montane rain forest according to the Holdridge [1967] life zone system).

Geographical distribution. This species is known only from the Caribbean slope of the Central Cordillera of Costa Rica ( Fig. 5 ).

Chorological affinities. The distribution of this new species represents, together with C. moniliatus , the northernmost distribution of the members of the “ Scybalocanthon ” group.

Taxonomic relationships. Canthon inusitatus seems to have a number of different characters from the other species of the “ Scybalocanthon ” group, which Medina et al. (2003) have concluded is an artificial group. Canthon inusitatus will key to C. moniliatus Bates in couplet 8 in the Solís and Kohlmann (2002) key to the Canthon of Costa Rica. However, these two species differ in several characters and C. inusitatus can be easily separated from C. moniliatus by color (body all black versus head and elytra black and pronotum yellow­brown), male protibial spur (broad versus slender), and femoral color (unicolored versus black and yellow).

Etymology. The word inusitatus is a Latin adjective in the nominative singular case, meaning unusual or extraordinary, in reference to such a big species having been found in such an unusual place for a Canthon , a cloud forest, after more than fifteen years of systematic collections in the area.

Figures

FIGURE 5. Known distribution of Canthon inusitatus in Costa Rica.