Mecyclothorax ramagei, Liebherr, James K., 2013

Liebherr, James K., 2013, The Mecyclothorax beetles (Coleoptera, Carabidae, Moriomorphini) of Tahiti, Society Islands, ZooKeys 322, pp. 1-170 : 48-49

34. Mecyclothorax ramagei sp. n.

Diagnosis.

Beetles of this species (Fig. 22E) look like smaller-sized versions of those comprising the sympatric Mecyclothorax teatara (Fig. 23D), but the presence of only the posterior supraorbital seta diagnoses this species from all others in the Mecyclothorax dannieae group; setal formula 1221; standardized body length 4.6-4.8 mm. The pronotum is more transverse than that of Mecyclothorax teatara ; MPW/PL = 1.27-1.30 (n = 2) in this species versus MPW/PL = 1.25 (n = 2) in Mecyclothorax teatara . Head with frontal grooves subparallel, shallow behind with small transverse wrinkles emanating onto frons, broad and deep anteriorly near the frontoclypeal suture; eyes moderately convex on little protruded ocular lobes, ocular ratio 1.44-1.51, ocular lobe ratio 0.83-0.86, a broad shallow groove at juncture of gena and hind portion of lobe; antennae moderately elongate, antennomere 8 length 1.80 × maximal breadth. Pronotum transverse, lateral margins broadly convex from tightly rounded, little protruded front angles to obtuse-rounded hind angles; basal pronotal setal articulation causing jag in margin and a very brief sinuation anterad the seta; median base moderately depressed relative to disc, very smooth, with 6-9 sparsely distributed, shallow punctures each side, margin of base and disc lined with elongate punctures and fine longitudinal wrinkles; basal pronotal margin broadly convex between the hind angles; anterior transverse impression complete medially, anterior margin upraised at anterior callosity, impression crossed by 3-7 longitudinal wrinkles each side in median 2/4s, the wrinkles variously continued across the anterior callosity; apical width noticeably less than width across hind angles, APW/BPW = 0.81-0.85; lateral marginal depression moderately narrow, the margin upturned, depression not wider inside front angles; laterobasal depression very smooth, broad, broadly margined laterally and basally, evenly upraised anteriorly to meet disc. Elytra broadly ovate, basal groove evenly curved, humerus tightly rounded, and lateral margin broadly extended posterad humerus; disc flat between the third intervals each side, sides moderately sloped to lateral marginal depression; discal elytral striae 1-5 moderately deep, smooth, the associated intervals broadly, slightly convex, striae 6-7 slightly shallower, minutely punctate; apex with striae 1-6 moderately deep, stria 7 deeper and broader apicad subapical sinuation, interval 8 no more convex than inner intervals; lateral elytral setae 7(8) + 6. Microsculpture of vertex a shallow, transverse mesh, sculpticell breadth 2 –4× length; pronotal disc with elongate transverse mesh, sculpticell breadth 3 –5× length, intermixed with transverse lines; pronotal median base with evident transverse mesh, breadth 2 × length, on the flat cuticle among the punctures; elytral disc with distinct transverse mesh, sculpticells 2 × broad as long, plus transverse lines. Coloration of head rufous with a piceous cast, clypeus rufous, labrum rufoflavous; antennomere 1 flavous, 2-4 rufoflavous; 5-11 rufobrunneous; pronotal disc rufobrunneous, median base and anterior callosity concolorous, lateral marginal depressions slightly paler; elytral disc rufous with a silvery metallic reflection, apex narrowly flavous, lateral marginal depression rufoflavous outside the lateral elytral setal series; femora rufoflavous with subtle smoky cast medially, tibiae rufoflavous with brunneous cast.

Male genitalia. Aedeagal median lobe broad in basal half, evenly narrowed to apex of ostium, lobe apex narrowly extended beyond ostium, expanded into a narrowly spatulate tip with blunt dorsal expansion (Fig. 24D); ostial canal extended from ostium along dorsal margin of lobe’s right side, terminated ventrad blunt dorsal expansion; flagellar plate relatively short, length 0.4 × distance from parameral articulations to apical face; right paramere narrowed apically.

Female gonocoxae. The female allotype was not dissected, but examining the distended abdomen (Fig. 22E) allows the following observations: basal gonocoxite 1 broad (dimensions similar to those in Fig. 8E), with 2-3 apical fringe setae laterally and one apical seta near medioapical angle; 7-11 setae arrayed from apex to base of mesal half of gonocoxite ventral surface; apical gonocoxite 2 narrow basally, subtriangular, with two lateral ensiform seta, the basal seta longer and narrower at base, and one dorsal ensiform seta; apical sensory furrow with two apical nematiform setae.

Holotype male (MNHN) labeled: FRENCH POLYNESIA: Tahiti Iti / Mont Atara, 815 m el. / 17°47.4425'S, 149°14.8103'W / 20-ix-2012, T. Ramage, Winkler / extraction of mossmat siftate // PF 1135 // HOLOTYPE / Mecyclothorax / ramagei / J.K. Liebherr 2013 (black-bordered red label).

Allotype female (MNHN) labeled as holotype // ALLOTYPE / Mecyclothorax / ramagei / J.K. Liebherr 2013 (black-bordered red label).

Etymology.

The species epithet is a patronym honoring the collector, Thibault Ramage, entomological consultant, Concarneau, France.

Distribution and habitat.

This species is distributed on the Tahiti Iti volcano. The type series was obtained by sifting mossmats on tree trunks, and extracting the insects from the siftate using a Winkler extractor (T. Ramage pers. comm.).