Tropopterus fieldianus, 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

9. Tropopterus fieldianus sp. nov. Figures 2C , 5 E–F , 6L , 9I , 10

Diagnosis

(n = 2). Like T. minimucro this species lacks the basal elytral groove and has the sutural stria punctate on the elytral disc. But unlike that species, T. fieldianus has both elytral stria 1 and 2 punctate subapically: stria 1 is deeply and narrowly impressed at the apex, whereas stria 2 is broadly, shallowly continuous there. The pronotum of this species is broad (MPW/PL = 1.37-1.39) and rather quadrate, broad basally with MPW/BPW = 1.18-1.25 (compared to the basally narrowed, more cordate pronotum of T. minimucro ; MPW/BPW = 1.24-1.33). The eyes are very convex with 26 ommatidia intersected by a horizontal diameter, and an eye convexity ratio, EyL/EyD = 2.4. The pronotal median base is rugosely punctate mesad the laterobasal depressions, and the anterior pronotal margin is smooth medially and margined along the outer 1/3 of each side. Ventrally the prosternum is broadly, moderately depressed medially, the depression extended 2/3 the distance from prosternal process to anterior margin, with the depression shallow and broad between the coxae. The mesepisternum bears a single dorsoventral row of 4-6 punctures, and the metepisternum and metepimeron are fused laterally, the suture difficult to trace except mesally near the metacoxa. Dorsally the head is glossy with very shallow isodiametric sculpticells visible across the surface, and the pronotum and elytra bear dense elongate transverse sculpticells and transverse lines resulting in iridescence. Standardized body length = 6.7-7.8 mm.

Description.

Head capsule broad, eyes convex, ocular ratio = 1.42-1.44; antennae moderately elongate, antennomere 9 length 1.96 × maximal diameter; mandibles elongate, distance from anterior condyle to apex of left mandible 1.96 × distance from condyle to lateroapical margin of labrum; mentum basal breadth 3.0 × length from lateral apex to base, very deep paramedial pits laterad base of mentum tooth; ligular apex broad, truncate, two setae separated by 4 setal diameters; paraglossae extended beyond ligular margin as far as distance from their base to ligular margin. Pronotum transverse, lateral margins nearly straight basally, briefly concave anterad right to slightly obtuse, denticulate hind angles; basal marginal bead complete, well developed medially; median base smooth; median longitudinal impression continued to basal marginal bead, lenticularly depressed near front of median base, finely inscribed on disc; anterior transverse impression obsolete medially, broad and shallow approaching front angle; front angles slightly protruded, obtuse-rounded; lateral marginal depression narrow in anterior half of length, evenly broadened from lateral seta to base; lateral seta separated from lateral marginal depression by diameter of setal articulatory socket. Elytra broad, lateral margins subparallel; parascutellar striole absent, sutural stria interrupted basally, terminated in broad, irregular depression surrounding parascutellar seta; stria 8 present near posterior setae of anterior lateral elytral setal series, shallow and interrupted near midlength, deep and continuous mesad posterior setal series; lateral marginal depression moderately broad from humerus to midlength, gradually narrowed to subapical sinuation; subapical sinuation broadly concave, moderately deep, plica well evident in dorsolateral view. Metepisternum slightly elongate, maximal width 0.83 × lateral length. Abdomen with ventrites 3-6 longitudinally depressed laterally; suture between ventrites 1 and 2 slightly sinuate laterally, ventrite 2 depressed within slight sinuation; abdominal ventrites 4-6 depressed basally, minutely strigose along intersegmental membranes; male apical abdominal ventrite with two setae each side, in one specimen median two setae more basally positioned, in the other two bilateral pairs of apical setae complemented by three shorter medial setae in the position usually observed in female specimens. Coloration (based on apparently, slightly teneral individuals) paler, head capsule rufopiceous, pronotum and elytra rufobrunneous; legs paler, rufoflavous; thoracic and abdominal ventrites brunneous, proepipleuron and elytral epipleuron paler, rufoflavous.

Male genitalia (n = 2). Aedeagal median lobe broad dorsoventrally with broadly rounded apex, a minute mucro on the ventrobasal margin of the apex ( Fig. 5E ); internal sac armature including flagellum and flagellar sheath. Antecostal apodeme of abdominal IX broadly rounded distally, with juncture of two lateral arms asymmetrically offset toward left side, distal extension broadly rounded (teneral specimen). Right paramere elongate, broader near midlength, narrowed evenly to apex, ventral surface lined with 16 small setae, two larger setae at apex, three subapical setae, and two very small setae on dorsal surface; left paramere very broad for much of length, terminated apically by a evenly narrowed projection with two larger apical setae, a third smaller subapical seta, plus several very small setae on apical process or ventral margin.

Holotype male ( FMNH), point mounted with left mesotarsomeres glued to point: CHILE: Osorno Prov., 3 / km S Maicolpue, Bahia / Mensa, 200 m, / 21.XII.1984 // FMHD#85-933, mixed forest litter, S. &J. / Peck, P85- 48 / berlese / FIELD MUSEUM NAT. HIST. // Tropopterus / Measured / Specimen #1 / det. J.K. Liebherr 2019 // dissection vial // Tropopterus / fieldianus / Liebherr ♂1 / det. J.K. Liebherr 2019 // HOLOTYPE / Tropopterus / fieldianus / J.K. Liebherr 2019 (black-margined red label).

Paratype: CHILE: Valdivia, 35 km WNW La Union, 7.xi.1985, 700m el., Mixed forest, S. Peck, P#85-114, FIELD MUSEUM ( FSCA, 1)

Etymology.

The species epithet fieldianus combines the noun field with the adjectival ending -anus, thereby signifying that this species belongs to the Field Museum. This “belonging” is based on the Field Museum’s institutional dedication to Coleoptera systematics signified by a long succession of beetle curators: John E. Liljeblad, Rupert L. Wenzel, Henry S. Dybas, Harry G. Nelson, Larry E. Watrous, Steve Ashe, Alfred F. Newton, and Margaret K. Thayer.

Distribution and habitat.

This species is known only from two localities ( Fig. 9I ) distributed near latitude 40°S in the northern portion of the Southern Valdivian entomofaunal province ( O’Brien 1971). It has been recovered from Berlese siftate of mixed forest litter. At the La Union site in Valdivia Prov., it was collected alongside the leiodid species Anaballetus chilensis ( Newton et al. 2017).

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 5. Male aedeagal median lobe, left view, and antecostal apodeme and tergite of abdominal IX, dorsal view. A-D. T. minimucro. A, B. Cautin Prov., Bellavista (EMEC). C, D. Llanguihue Prov., P. N. Vicente Perez Rosales (FMNH). E, F. T fieldianus. E. Osorno Prov., Maicolpue (FMNH). F. Valdivia Prov. La Union (FSCA). For abbreviations used to label structures see Table 1.

Figure 6. Paired sets of left parameres (above) and right parmeres (below), ectal view, for male specimens of Tropopterus spp. Parameres are in anatomically correct orientation with ventral surface toward bottom of drawing. A, B. T. giraudyi. A. Malleco Prov., P. N. Nahuelbuta (FMNH). B. Chili, " Tropopterus nitidus Sol. " [sic], Chaudoir Coll. (MNHN). C. T. peckorum; Quillota Prov., P. N. La Campana (FMNH). D, E. T. robustus. D. Malleco Prov., P. N. Contulmo (CMNH). E. Cautin Prov., Bellavista (CAS). F, G. T. canaliculus. F. Malleco Prov., P. N. Nahuelbuta (FMNH). G. Arauco Prov., Caramavida (NMNH). H-I. T. duponchelii. H. Talca Prov., Altos de Vilches (MNHN). I. Arauco Prov., Caramavida (MCZ). J, K. T. minimucro. J. Cautin Prov., Bellavista (EMEC). K. Llanquihue Prov. P. N. Vicente Perez Rosales (FMNH). L. T. fieldianus; Valdivia, La Union (FSCA).

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).