Mecyclothorax ehu, Liebherr, James K., 2013

Liebherr, James K., 2013, The Mecyclothorax beetles (Coleoptera, Carabidae, Moriomorphini) of Tahiti, Society Islands, ZooKeys 322, pp. 1-170 : 73-75

62. Mecyclothorax ehu sp. n.

Diagnosis.

This species shares with Mecyclothorax putaputa (Figs 32C, E) the little projected, hitch-like pronotal hind angles with pronotal lateral margins subparallel only outside the basal seta articulatory socket, but individuals of this species are larger, standardized body length 4.7-5.1 mm. The elytral striae are shallow with distinct rounded punctures on the disc that expand the breadth of the striae. The discal elytral intervals are only slight convex. Setal formula 2221. Head with laterally linear frontal grooves, posteriorly lined mesally with fine transverse wrinkles and bordered laterally by fine carina, moderately expanded anteriorly, with two grooves divergent at frontoclypeal suture; eyes convex on protruded ocular lobes, ocular ratio 1.53-1.62 (n = 5), ocular lobe ratio 0.86-0.90; antennae somewhat elongate, submoniliform, antennomere 8 length 1.8 × maximal breadth. Pronotum variably broad, moderately transverse to transverse, MPW/PL = 1.14-1.28, base similarly, variably constricted, MPW/BPW = 1.47-1.64; median base evenly depressed relative to convex disc, ~12 distinct punctures each side; anterior transverse impression broad, shallow, continuous across breadth, crossed laterally by ~9 fine longitudinal wrinkles that extend anterad across anterior callosity; front angles not protruded, rounded behind; lateral marginal depression narrow, margin upraised but not beadlike, depression slightly wider inside front angles; laterobasal depression an elongate expansion of lateral marginal depression, crossed near base by transverse bar that connects median base to the upraised lateral margin. Elytra ovate, lateral margin evenly curved posteriorly outside subangulate humerus, the humeri moderately proximate, MPW/HuW = 2.22-2.32; elytral disc moderately convex, sutural interval elevated relative to striae 2-6; striae 1-6 shallow to obsolete near elytral basal groove and humerus; apicad base, stria 6 shallower than striae 1-5, but still continuous, stria 7 interrupted through much of length, consisting of a series of isolated punctures except for deep canaliculated portion apicad fused terminus of striae 5 + 6; eighth interval increasingly more convex as it narrows near apex, appearing pinched, the mesal margin upraised and subcarinate along stria 7 near apex; lateral elytral setae 7 + 6. Microsculpture of frons an elongate transverse mesh, sculpticell breadth 2 –4× breadth, the sculpticells visible even in transverse wrinkles, neck with sculpticells 2 × broad as long; pronotal disc with indistinct transverse mesh visible outside areas of reflected light, sculpticell breadth 2 –3× length; discal elytral intervals lined with regular transverse mesh, the sculpticells distinctly bordered, sculpticell breadth 2 –4× length. Coloration of head rufous; antennomere 1 flavous, 2-3 rufoflavous, 4-11 rufobrunneous; pronotal disc rufobrunneous, margins narrowly paler, rufous; elytral disc rufous with a silvery reflection, sutural interval narrowly paler near scutellum, rufoflavous apically; elytral lateral marginal depression concolorous at humerus, contrastedly rufoflavous anterad subapical sinuation; femora rufoflavous, tibiae rufoflavous with brunneous cast.

Male genitalia. Aedeagal median lobe shaft broad, apex moderately extended beyond ostium and broad dorsoventrally (Fig. 30I), the apical face moderately oblique; internal sac with broad, diffuse ventral ostial microtrichial patch (Fig. 30J), flagellar plate elongate, length 0.5 × distance from parameral articulations to apical face; dorsal surface of flagellar plate with a broad median depression that includes gonopore, lateral reaches of dorsal membrane associated with plate lightly sclerotized.

Female reproductive tract. Bursa copulatrix ovately expanded apicad a slightly narrower vagina; bursal plus vaginal length twice as long as maximal breadth when compressed under cover slip (Fig. 33C); basal gonocoxite 1 narrow, elongate, with apical fringe of 4 setae, the middle pair doubled, 5-7 smaller setae along mesal margin, 1-3 of these near apex (Fig. 9D); apical gonocoxite 2 very broadly expanded lateroba sally, the lateral margin distinctly arcuate laterad the tightly rounded apex, two lateral ensiform setae and one dorsal ensiform seta, the latter extended laterally past lateral margin; apical sensory furrow with two apical nematiform setae and two sensory pegs.

Holotype male (MNHN) labeled: French Polynesia: Tahiti Nui / Pito Hito el. 2070 m 2-VI- / 2006 lot 01 pyrethrin fog / 17°36.813'S, 149°27.842'W / E.M. Claridge // HOLOTYPE / Mecyclothorax / ehu / J.K. Liebherr 2013 (black-bordered red label).

Allotype female (MNHN) labeled as holotype.

Paratypes: labeled as holotype (CUIC, 1; EMEC, 1); Pito Hiti, 2000 m el., 17°36.790'S, 149°27.842'W, 2-vi-2006 lot 02, Claridge, pyrethrin fog.

Etymology.

The species epithet ehu is taken from the Tahitian word 'ehu, meaning the color red. The name signifies the reddish coloration of beetles of this species.

Distribution and habitat.

This species is known from 2000-2070 m elevation on Pito Hiti, and based on collections made using pyrethrin fog, spends at least part of its life within arboreal mossmats.