Gorditus Ratcliffe

Ratcliffe, Brett C., 2010, Gorditus rotundus, a new genus and species of Pentodontini from Cuba (Coleoptera: Scarabaeidae: Dynastinae), Zootaxa 2683, pp. 56-60 : 57-59

Gorditus Ratcliffe , new genus

Type species. Gorditus rotundus here designated.

Description. Body form oval ( Fig. 1 ), highly vaulted posteriorly in lateral view ( Fig. 2 ). Length about 22 mm. Color reddish brown. Clypeus attenuate to a narrowly truncate apex. Interocular distance equals 6 transverse eye diameters. Antenna with 10 antennomeres, club subequal in length to antennomeres 2–7. Mandibles exposed, subtriangular. Pronotum with moderately dense, large punctures; lateral margins with long, reddish brown setae. Elytra smooth, impunctate except for some minute punctures on sides in posterior half. Pygidium completely rugulopunctate. Protibia quadridentate. Metatibia at apex bluntly rounded. Metasternum with anterior half punctate and posterior half smooth. Abdominal spiracles noticeably large, directed posteriorly.

Distribution. Cuba.

Diagnosis. This genus shares some similarities with Endroedianibe Chalumeau from the Dominican Republic, namely, the plump body form and the form of the apically constricted clypeus. The male parameres are also remarkably similar to those of E. bozzolai Chalumeau. However , G. rotundus is notable for its large interocular distance (six transverse eye diameters); presence of long, reddish brown setae on the lateral margins of the pronotum; smooth elytral surface; pygidium completely rugulopunctate; metasternum with anterior half punctate and the posterior half smooth; and the remarkably large abdominal spiracles that are directed posteriorly. None of these traits are shared with Endroedianibe species.

The abdominal spiracles are remarkably large and slightly protuberant, and they may have some correlation to life style or habitat. The fact that they are directed posteriorly is probably advantageous when burrowing through the soil, since soil might be less likely to enter the spiracle. However, many other soil dwelling dynastines do not have spiracles of this nature and seem not to have a problem with soil entering the spiracular opening. For the moment, then, the form of these unique spiracles remains an enigma.

Etymology. From the Spanish word “gordo,” meaning fat or plump, here used in the diminutive form, “gordito” for “little fat one” in reference to the small, plump body size. The genus is masculine in gender.

Figures

FIGURES 1 – 2. Gorditus rotundus, dorsal and lateral habitus views of holotype.