97. Mecyclothorax poro Liebherr, 2012b: 91

Identification.

Beetles of this species are most similar to those of Mecyclothorax spinosus and Mecyclothorax angulosus (Figs 48C, D, 49A), but differentially combine the following, therefore being diagnosable from both: 1, pronotum moderately transverse, MPW/BPW = 1.25 (n = 1), and moderately constricted basally, MPW/BPW = 1.56; 2, pronotal median base sparsely punctate, 10-12 small, isolated punctures each side surrounded by glossy cuticle, plus 7-8 elongate punctures each side along juncture with pronotal disc; 3, elytra broadly subquadrate, margins extended laterally outside subangulate humeri; 4, elytral striae 2-6 basally obsolete, not continuous to elytral basal groove. The frons and vertex of the head are glossy with an indistinct transverse mesh; sculpticell breadth 2 –3× length. The pronotal disc bears an indistinct transverse mesh visible outside areas of reflected light, sculpticell breadth 2 –4× length, and the discal elytral intervals are covered with transverse lines irregularly joined into an irregular mesh. Setal formula 2121; standardized body length 4.4 mm.

Distribution and habitat.

The single adult specimen was collected in moss on a low rockface along the Faatautia River as the river exits from a large, uncollapsed lava tube at 705 m elevation on Mont Mauru (see fig. 2A, Liebherr 2012b). This riparian situation is the lowest elevational habitat within which any Tahitian Mecyclothorax specimen has been discovered.