Mecyclothorax ataraensis Perrault, 1989: 63

Liebherr, James K., 2013, The Mecyclothorax beetles (Coleoptera, Carabidae, Moriomorphini) of Tahiti, Society Islands, ZooKeys 322, pp. 1-170 : 95-96

78. Mecyclothorax ataraensis Perrault, 1989: 63

Identification.

Along with the previous species, Mecyclothorax ataraensis is diagnosable within the Mecyclothorax globosus group by the presence of only the posterior supraorbital seta and anterior dorsal elytral seta - setal formula 1111 - in combination with transverse microsculpture on the discal elytral intervals, but this species is distinguished by standardized body length 3.3 mm; the smallest body size recorded for any Tahitian Mecyclothorax species. The eyes are small, ocular ratio 1.43, yet they cover nearly all of the small ocular lobes in dorsal view, ocular lobe ratio 0.92. The pronotum is constricted basally, MPW/BPW = 1.52, and the lateral margins are subparallel anterad the right hind angles (Fig. 39D). The discal elytral striae are shallow yet distinctly punctate, with deep rounded punctures that expand the strial breadth spaced about 4 × their diameter along the striae. The elytral intervals are broadly convex; each nearly flat medially. The head is glossy, with transverse wrinkles on the frons but no evident microsculpture. The pronotal disc bears an elongate transverse mesh, traceable outside areas of reflected light. The discal elytral intervals are lined with a distinct transverse mesh, the sculpticell breadth 2 –3× length. The species is currently known from two female specimens.

Distribution and habitat.

The holotype and paratype were collected between 900-1100 m elevation on Mont Teatara, Tahiti Iti.