Scybalocanthon batesi, Vaz-De-Mello & Silva, 2017

Vaz-De-Mello, Fernando Z. & Silva, Fernando A. B., 2017, A new species of the genus Scybalocanthon (Coleoptera, Scarabaeidae, Scarabaeinae) from the Atlantic rainforest, with an identification key to the species from South America south of the Amazon basin, Zootaxa 4300 (1), pp. 142-146 : 143-144

Scybalocanthon batesi sp. nov.

( Figures 1 –3)

Etymology. Named in honor of Henry Walter Bates (1825–1892), from whose collection specimens originally came from.

Diagnosis. S. batesi sp. nov. can be immediately differentiated from all the remaining species in the genus by elytra with a yellow horizontal band on its central portion occupying approximately one-third of elytral length ( Fig. 1 ); metepisternae dark brown or black ( Fig. 2 ); anterior and posterior margins of pronotum with a triangular black spot on the middle portion; pygidium not separated from propygidium by carina.

Description. Colour. Head, anterior and posterior edge of pronotum, anterior and posterior portions of elytra, prosternum, internal edge of hypomera, mesosternum, mesoepisternae, lateral portions of metasternum, metepisternae, procoxae, trochanters, basal and apical parts of femurs, tibiae, meso and metatarsomeres, dark brown or black; other parts of the pronotum, horizontal band on the middle portion of elytra, pygidium, most of the hypomera, central portion of metasternum, abdomen, most of the meso and metacoxae, and femora (except the extremities) yellowish-brown color. Length. 8 mm. Head. Dorsal surface with fine microgranulation. Clypeal margin with two small, triangular central teeth, sharp, separated by a U-shaped notch. Margin between clypeal teeth and clypeo-genal suture almost straight. Margin of gena curved outward. Clypeo-genal suture slightly impressed. Dorsal interocular width twelve times the eye width. Posterior dorsal margin of head (occipital region of front) completely margined by fine carina. Thorax. Surface of pronotum finely punctate and glabrous, punctures noticeable only at high magnification. Lateral pronotal impressions inconspicuous. Anterior and posterior margins of pronotum with triangular spot on the middle portion. Pronotum twice as wide as long, anterior angles acute, directed forward. Border of pronotum finely margined, margination discontinued on postero-lateral portions. Margin between lateral and posterior angles oblique, slightly curved outward. Hypomera not excavated; lacking carina separating the anterior and posterior portions. Mesometasternal suture straight. Metasternum moderately convex. Elytra. Elytral striae weakly impressed, with punctures almost inconspicuous. Eighth stria with a thin carina at the base. Basal third of eighth stria inconspicuous (except the basal carina). Width of sixth interstria at base about one-half width at midway point. Abdomen. Lateral portion of ventrites 3, 4, 5, and 6 densely setose. Pygidium rounded apically, clearly margined; not separated from propygidium by carina. Legs. Surfaces of meso- and metafemora glabrous. Anterior and posterior borders of meso- and metafemur not margined. Mesotibiae smoothly arched toward body. First meso and metatarsomeres short, about half the length of second tarsomere, obliquely truncated at apex. Tarsal claws without basal teeth.

Type material. Holotype. BRAZIL: BAHIA, 1892, H. W. Bates (1♀ MNHN) . Paratypes. BRAZIL: [no data] (1♀ MNHN, 1 ♀ CEMT) .

Distributional remarks. The above description was based on three female specimens, males are unknown. This species was described based on specimens collected in the nineteenth century, deposited in MNHN. So far, extensive sampling in some parts of the Atlantic forest located in Bahia state (type locality) has provided no recent specimens of S. batesi sp. nov.. Thus, as the Atlantic rainforest (supposed habitat for this species) is a greatly threatened habitat and the last known record for this species was from 1892, there was good reason to consider S. batesi sp. nov. critically endangered or presumed extinct according to IUCN Red List Categories and Criteria ( IUCN, 2001).

Figures

FIGURES 1 – 2. Scybalocanthon batesi sp. nov.; 1. dorsal view; 2. ventral view; Figure 3. Known distribution of S. nigriceps, S. zischkai, S. korasakiae and S. batesi sp. nov..