Thoracophorus proximus Irmler, 1985

Irmler, Ulrich, 2015, Four new species of the genus Thoracophorus Motschulsky, 1857 for the Neotropical region (Coleoptera: Staphylinidae: Osoriinae), Zootaxa 4039 (3), pp. 431-444 : 439-440

Thoracophorus proximus Irmler, 1985

Figs. 6 A, B, C, 10F

Type material examined. See Irmler (1985) Further material examined. Belize: 1 specimen, Olancho (86°42’W, 15°06’N), wet montane forest, litter, 1450 m elev. collected by Berlese, 16.8.1994, leg. R. Anderson ( CNC); Honduras: 1 specimen, Gracias (88°31’W, 14°41’N), litter, 18.6.1994, leg. R. Anderson ( CNC); Nicaragua: 2 specimens, Matagalpa Dept., 6km N Matagalpa, Selva Negra (12°59.9’N, 85°54.6’W), 1250 m elev., collected by flight intercept, 18– 22.5.2002, leg. S. Peck (1 KNHM, 1 UIC); Costa Rica: 2 specimens, Guanacaste, Conservation area (85°07’W, 10°42’N), 17.2.1996, leg. R. Anderson ( CNC); 1 male, 1 female, Osa Peninsula, Rd. Bahia Drake> Rincon de Osa (8°41’– 42’N, 83°29’–40’W), 0–400 m elev., collected by car net, devastated forest & plantations 9.12.2012, leg. Schülke & Grünberg (1 MSC, 1 UIC); Panama: 2 specimens, Chiriqui, El Mirador, 6000’ elev., Finca Collins n. Boquete, polypore tree fungus, 25.6.1976, leg A. Newton (1 FMNH, 1 UIC); Brazil: 3 males, 2 females, Nova Teutonia (52°23'W, 27°11'S), 5.3.1950, 25.2.1950, 17.2.1950, 20.8.1944, 7.8.1944, leg. F. Plaumann ( BMNH).

Diagnosis. The species T. proximus Irmler, 1985 , T. exilis ( Erichson, 1840) , T. aequalis Sharp, 1887 , T. perplexus n. sp., and T. struyvei n. sp. are extremely similar. For the identification a microscope analysis of the aedeagus is needed. T. proximus Irmler, 1985 is characterised by the obtuse posterior angle of the temples. The shape of the pair of posterior swellings on the vertex is similar as in T. perplexus n. sp. and T. struyvei n. sp., whereas they are more distinct in T. exilis ( Erichson, 1840) and T. aequalis Sharp, 1887 . Beside the aedeagal characters already mentioned in Irmler (1985), the short and narrow transparent field at the apex of the paramera, the straight inner edge of the central lobe and the exceeding apex are additionally characteristic.

Description. Length: 1.7–1.9 mm. Colouration: reddish brown, elytra at shoulders and laterally dark orange, near suture more blackish; legs and antennae yellow.

Head: 0.22 mm long, 0,29 mm wide; eyes prominent; twice as long as temples; temples shortly narrowed to neck in short convex curve, behind eyes acutely prominent; teeth-like; posterior angles of temples approximately 135°; eyes 1.5 times as long as parallel part in front of eyes; clypeus approximately triangular with obtuse central part; sides margined from anterior edge of eyes to central angle; pair of swellings on posterior half of vertex present, but indistinct; without punctures; narrow isodiametric microsculpture dense and deep; surface matte.

Antenna as long as head and half of pronotum combined; first and second antennomere thicker and longer than third; third antennomere conical; fourth and fifth slightly wider than long; following antennomeres increasing in width; penultimate three antennomeres nearly twice as wide as long.

Pronotum: 0.28 mm long, 0.33 mm wide; widest at middle; slightly and continuously narrowed to anterior angles; anterior angles rectangular; central part of anterior edge prominent in slight convex curve; strongly narrowed to posterior angles; anterior edge one third wider than posterior edge; lateral longitudinal impressions and central impression present, but not deep; central prominence indistinct; without punctures; narrow isodiametric microsculpture deep and dense; surface matte.

Elytra: 0.37 mm long, 0.38 mm wide; sides parallel; shoulders and posterior angles equally rounded; three carinae on each side of suture; space between inner carina and suture slightly wider than between carinae; without punctures; narrow isodiametric microsculpture deep and dense; slightly coarser than on head and pronotum; surface matte.

Abdomen at segments III and IV with transversal impression at base; without punctures, but with minute sparse yellow scales; isodiametric microsculpture less deep than on fore-body; surface glossier.

Aedaegus continuously curved from basal lobe to apex; with indistinct obtuse angle between basal and apical lobe; apex of central lobe distinctly exceeding ventral sclerotised plate; inner bulb thick with long straight ductus; paramera longer than central lobe; transparent plate at apex of paramera slightly wider than middle part of paramera; approximately six sensillae at base of paramera.

Figures

FIGURES 4 – 8. Thoracophorus struyvei (4); T. perplexus (5); T. proximus (6); T. exilis (7); T. aequalis (8); aedeagus in lateral aspect (A), antenna (B), shape of temples (C); scale bar: 0.1 mm.