Canthochilum xericum Philips & Ivie

Philips, Keith & Ivie, Michael A., 2008, Seven new species of Canthochilum Chapin from Hispaniola (Coleoptera: Scarabaeidae: Scarabaeinae), Zootaxa 1730, pp. 27-42 : 36-37

Canthochilum xericum Philips & Ivie , new species

Figs. 31–33 , 40 , 43

Diagnosis. The elytron evenly rounded laterally, without a trace of a carina or angulate margin between seventh and eighth striae is one characteristic for this species. Additionally, the head surface is distinctly shagreened on the anterior half, with the remaining surface mainly smooth (except for fine punctures), a condition that is unique among known members of the genus.

Description (male). Body oblong, black, legs and anterior edge of clypeus dark reddish-brown ( Fig. 43 ); anterior portion of dorsal surface of head with fine punctures separated by 6 to 9 X their diameter, surface shagreened anteriorly, extending slightly further posteriorly mesally, vertex with more distinct punctuate separated by 4– 5 X their diameters, surface shining; clypeus with 4 teeth, mesal teeth acute, tips blunt, lateral teeth relatively very small, obtusely pointed, 2 additional projections near clypeal-genal suture barely apparent ( Fig. 31 ); dorsal ocular area large, eyes separated by a distance equal to 3.5 to 4X their transverse width ( Fig. 31 ); elytral striae distinct, with fine punctures along length; elytral intervals very slightly convex, very fine scattered punctures visible under high magnification, surface finely shagreened; elytra evenly rounded laterally, without trace of lateral carina or angulate margin between seventh and eighth striae, punctures of eighth stria coarse continuous to level of metacoxa, then becoming obsolete; protibiae with 3 teeth, distal end nearly truncate with very slight bending obliquely forward beginning at distal tooth ( Fig. 32 ); protibial spur blunt, reaching third tarsomere; metatibia slightly curved; mesosternal suture anteriorly obtusely angled; pygidium entirely margined, strongly convex, surface finely punctured and smooth; aedeagus with basal piece apex with an elongate approximately parallel sided process, parameres small and bifurcate ( Fig. 33 ). Length: 3.1 – 3.5 mm, measured along midline from anterior margin of pronotum to tip of elytra.

Female. Differs from the male in having the protibial spur narrower and acute.

Types. HOLOTYPE MALE, ALLOTYPE FEMALE — DOM.REP.: Pedernales; 4 km W Oviedo, 10m; arid thorn forest; 28.XI – 4.XII.91; intercept trap; Masner & Peck, 91-344 [CMNC]. PARATYPES. 4 MALE, 8 FEMALE — same data as holotype [CMNC, MNHD, TKPC, WIBF].

Etymology. This species is found in arid thorn forest and the other species are known from moist forest, thus the name “ xericum ” indicates the habitat preference for this particular species.

Notes. This species was initially hidden among a series of another species that was superficially similar. The labels indicating it was from desert region, as opposed to the rest of the group being from wet areas, was the first indication that something unique was represented. Discovery of this species indicates that more exploration is needed in dry areas.

Figures

FIGURES 31 – 33. Canthochilum xericum. 31. Head, dorsal view; 32. Protibia, dorsal view; 33. Male genitalia, lateral view.

FIGURES 38 – 40. Dorsal habiti. 38. Canthochilum nebulonemi; 39. Canthochilum ciboney; 40. Canthochilum xericum.

FIGURES 43 – 45. Elytral lateral angles (and part of pronotal base). 43. Evenly rounded (Canthochilum xericum); 44. Trace of angulate edge (Canthochilum nebulonemi); 45. Distinct angulate margin (Canthochilum matthewsi). FIGURES 46 – 47. Elytral apices. 46. Rounded intervals and transversely carinate or subcarinate (Canthochilum matthewsi); 47. Flat intervals and lacking distinct transverse ridge (Canthochilum ciboney).