Mecyclothorax laevilateralis Perrault, 1989: 67

Liebherr, James K., 2013, The Mecyclothorax beetles (Coleoptera, Carabidae, Moriomorphini) of Tahiti, Society Islands, ZooKeys 322, pp. 1-170 : 114-115

100. Mecyclothorax laevilateralis Perrault, 1989: 67

Identification.

Beetles of this species bear superficial similarity to Mecyclothorax spinosus and Mecyclothorax profondestriatus (Figs 38B, 48C, 49C), the three species sharing a little transverse, basally constricted pronotum and bronzed dorsal body coloration. However beetles of both other species exhibit elytra with striae 6-7 as deeply incised as the inner five striae, whereas this species is characterized by the lateral striae 6-7 being shallower than the inner striae, with the impunctate stria 7 so shallow that it is nearly interrupted along its length. The elytra of these beetles are more narrowly obovate with more punctate striae (Fig. 49C) than the basally broad, ovate elytra characterizing Mecyclothorax spinosus (Fig. 48C). Conversely, the pronotum is more constricted basally - MPW/BPW = 1.56-1.58 (n = 4) - than observed in individuals of Mecyclothorax profondestriatus ; MPW/BPW = 1.51-1.53 (n = 2). The frons is glossy with no apparent sculpticells (the shagreened frontal condition of the photographed male [Fig. 49C] is not observed in other specimens), and the pronotal disc is glossy with transverse lines visible near the margins of reflected light. The discal elytral intervals are glossy with only limited areas of transverse mesh visible across the highly reflective surface. The male aedeagal median lobe is small relative to the male body size in comparison to Mecyclothorax spinosus (Figs 47G versus 47I), but of similar relative size to that of Mecyclothorax profondestriatus (Figs 40D, 47I). The median lobe is evenly arcuate with a simple apex that has a slightly downturned tip; a similar though less exaggerated conformation than observed in Mecyclothorax profondestriatus males. Setal formula 2121; standardized body length 3.6-4.1 mm.

Distribution and habitat.

This species has been recorded from 900-1100 m elevation on Mont Teatara, Tahiti Iti. All specimens with ecological data have been associated with moss-covered trunks or horizontal logs, with collections made by beating small trunks or through application of pyrethrin fog to downed logs.