Tropopterus trisinuatus, Liebherr, James K., 2019

Liebherr, James K., 2019, Revision of Tropopterus Solier: A disjunct South American component of the Australo-Pacific Moriomorphini (Coleoptera, Carabidae), Deutsche Entomologische Zeitschrift 66 (2), pp. 147-177 : 147

7. Tropopterus trisinuatus sp. nov. Figures 2A , 9G , 10

Diagnosis

(n = 2). Although the pronota of all Tropopterus have the basal margin slightly undulated and medially convex, beetles of this species exhibit an exaggeration of this sinuation, with the base profoundly concave just mesad the acute hind angles in association with the deep laterobasal depressions ( Fig. 2A ). This Tropopterus also exhibits the largest body size; standardized body length of 8.2-8.4 mm larger than all but the largest individuals of T. giraudyi . The eyes are large in diameter though little convex, with an ocular ratio = 1.36 and a horizontal diameter crossing the eye intersecting 25-26 ommatidia. The sutural stria is punctate, the isolated punctures joined in part by indistinctly depressed strial connections, and the parascutellar striole is absent, the sutural stria vaguely continued to the elytral base as a broad depression. The outer elytral striae are progressively reduced, with striae 2 and 3 traceable as a series of minute, isolated punctures, and a very few minute punctures visible in the position of stria 4. Stria 8 just dorsad the lateral elytral setae is continuous throughout its length. As in T. minimucro and T. fieldianus , the elytral basal groove is absent; the elytral surface evenly and smoothly convex inside the anterior termination of the lateral marginal depression at the toothed humerus. Ventrally, the prosternum is broadly and deeply depressed from the prosternal process anterad 2/3 the distance to the pronotal anterior margin, and the mesepisternum is punctate, with ~18 punctures arranged in 2 or 3 vertical rows broadly distributed across its surface. Microsculpture of the vertex is an evident isodiametric mesh with sculpticells arranged in transverse rows in part. The pronotum is covered with a dense transverse mesh with sculpticells of breadth 3 –4× length, complemented by transverse lines, and the elytra are covered with dense transverse lines producing iridescence.

Description.

Head capsule broad, ocular lobe little protruded; antennae moderately robust, length of antennomere 9 2.0 × maximal diameter; mandibles elongate, but given large head, distance from anterior condyle to apex of left mandible only 1.80 × distance from that condyle to lateroapical margin of labrum; mentum basal breadth 3.05 × length from lateral apex to base, very deep paramedial pits laterad base of mentum tooth; ligular apex broad, truncate, two setae separated by four setal diameters; paraglossae extended beyond ligular margin slightly more than distance from their base to ligular margin. Pronotum moderately transverse, lateral margins distinctly sinuate anterad right to slightly acute hind angles; base with complete marginal bead, median base smooth medially, with approximately eight small punctures each side mesad laterobasal depression; median longitudinal impression with lenticular depression on median base, finely etched on disc; anterior transverse impression traceable medially, broad and shallow laterally; anterior margin smooth in medial 1/3, margined in lateral 1/3 each side; front angle protruded, subangulate; lateral marginal depression narrow from apex to lateral seta, widened in basal 1/3 of length; lateral seta separated from lateral marginal depression by diameter of setal articulatory socket; laterobasal depression margined medially by deep, sinuous impression, an upraised tubercle in middle of depression; proepisternum smooth dorsally, with broad irregular punctures near prosternal suture. Elytra broad basally, sides subparallel; humerus angulate with short extension of basal groove mesad angle; sutural stria with closely set yet isolated punctures on disc, punctures larger toward apex, but stria deep, narrow and smooth distad subapical sinuation; stria 8 deep and continuous throughout length; seven or eight anterior lateral elytral setae, six posterior setae; lateral marginal depression very narrow anteriorly, broader in apical half, lined there with transverse sculpticells; subapical sinuation broad and shallow, elytral plica visible in lateral view. Metepisternum equitrapezoidal, maximal width subequal to lateral length; metasternal process with a rounded apical knob, the lateral margins narrowly upraised. Abdomen with ventrites 3-5 longitudinally depressed laterally; suture between ventrites 1 and 2 sinuate, ventrite 2 depressed posterad sinuation; ventrites 4-6 depressed basally, the intersegmental membranes minutely punctate; female apical ventrite with two setae laterally each side and an elongate quadrangle of subequally-lengthed setae medially. Coloration of body dark, head, pronotal disc and elytra piceous, the latter with iridescent surface; antennae, mouthparts and legs brunneous; ventral surface piceous, pterothoracic and abdominal ventrites, and elytral epipleura iridescent, only apical 1/6 of apical abdominal ventrite paler, rufobrunneous.

Female reproductive tract (n = 2; females not dissected, only accessible gonocoxal characters described). Basal gonocoxite 1 with one apical fringe seta; apical gonocoxite 2 narrowly triangular, base not extended laterally, with two lateral ensiform setae, one dorsal ensiform seta, and two apical nematiform setae.

Holotype female ( CAS): CHILE: Cautin Province, / Villarrica, 1250 m, trap / site 653, 15 - 29 Jan 1982 / Nothofagus domb.-pumilio / forest w/ Chusquea / A.F. Newton & M.K. Thayer // Tropopterus / trisinuatus / sp. nov. ♀1 photo / det. J.K. Liebherr 2019 // Tropopterus / Measured / Specimen #1 / det. J.K. Liebherr // HOLOTYPE Tropopterus / trisinuatus / J.K. Liebherr 2019 (black-margined red label). The type locality is Volcán Villarrica, 1250 m el.; geographic coordinates 39°22.8'S, 71°56.4'W (A.F. Newton, pers. comm.).

Paratype with identical data ( CAS, 1).

Etymology.

The adjectival species epithet trisinuatus signifies the trisinuate basal pronotal margin that unique characterizes this species among those known.

Distribution and habitat.

This species is known only from the type locality in the Northern Valdivian entomofaunal province ( O’Brien 1971). The two specimens were collected in a mixed forest of large Nothofagus dombeyi (Brisseau de Mirbel), N. pumilio (Poeppig and Endlicher), and Chusquea bamboo. The forest was near a recent lava flow, and the soil was thin. The specimens were collected from the ground-level microhabitat, either in a flight intercept trap catch pan, or in a leaf litter sift sample. The two types were collected at the same place and time as part of the type series of the oribatid mite Novonothrus puyehue Casanueva and Norton (1997).

Figures

Figure 2. Tropopterus spp., dorsal view; range of standardized body lengths in mm. A. T. trisinuatus female; Cautin Prov., Villarrica (CAS). B. T. minimucro female; Valdivia Prov., P. N. Oncol (OSAC). C. T. fieldianus male; Osorno Prov., Maicolpue (FMNH).

Figure 9. A-I. Geographic distributions of Tropopterus spp. A. T. montagnei. B. T. giraudyi. C. T. peckorum. D. T. robustus. E. T. canaliculus. F. T. duponchelii. G. T. trisinuatus. H. T. minimucro. I. T. fieldianus. J. Geographical distributions of Tropopterus spp., labeled as per figures above, hierarchically arranged by phylogenetic relationships of the taxon cladogram, Fig. 10.

Figure 10. Cladogram returned under all cladistic protocols described in text; tree length = 97, CI = 57, RI = 47, fast character optimization shown. Outgroup choice of Pharetis thayerae based on results in Liebherr (2020). Geographic region abbreviations after taxon name include: eastern Australia (EOZ); Santiagan entomofaunal province (San); Northern Valdivian entomofaunal province (NV); Southern Valdivian Entomofaunal province (SV).