Thoracophorus filum Sharp, 1887

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 : 432-434

Thoracophorus filum Sharp, 1887

Figs 1 A, 'A, B, 9A, B

Type material examined. SYNTYPES: Guatemala: 3 females: El Tumbador, leg. G.C. Champion ( BMNH); 1 female El Zapote, leg. G.C. Champion ( BMNH); 1 female El Reposo, leg. G.C. Champion ( BMNH).

Additional material examined. Argentina: Iguazú, rainforest litter, (54°23.32’W, 25°43.09’S), Berlese, 23.09.1998, leg. Leponce, M. ( IRSB); Iguazú, rainforest litter, #T2 (54°21.17’W, 25°42.16’S), Berlese, 23.09.1998, leg. Leponce, M. ( IRSB); Bolivia: 2 specimens, Cochabamba, Lagunitas, 117 km E Yungas, montane forest litter, 1000 m elev. (65°40.57’W, 17°52.2’S), flight intercept trap, 8.2.1999, leg. Anderson, R. ( KNHM, UIC); Brazil: 6 specimens, Nova Teutonia (52°23’W, 27°11’S), leg. Plaumann, F. ( FMNH, AMNH); Nova Teutonia, 1.10.1922, leg. Plaumann, F. ( CNC); 1 specimen, Nova Teutonia, 15.02.1941, leg. Plaumann, F. ( FMNH); Colombia: 1 specimen, Leticia, leaf litter (69°55’W, 4°12’S), 9.7.1970, leg. Campbell, J.M. ( CNC); Costa Rica: 1 specimen, Hamburg Farm, Reventazon, Ebene von Limon (84°13’W, 9°54’N), under bark, leg. Nevermann, F. ( FMNH); 1 specimen, Heredia (83°59’W, 10°26’N), flight intercept trap, 1.2.1992, leg. Bell, W ( KNHM); 1 specimen, Guanacaste, Lomas Barbudal Biological Res., dead log, 17 m elev. (85°22.15’W, 10°30.22’N), 1.7.2000, leg. Ashe, J. ( KNHM); 1 specimen, Rincon de Osa (83°31’W, 8°41’N), 26.6.2001, leg. Peck, J. ( KNHM); 1 specimen, Rincon de Osa, Rd. Barrigones Chacarita, pasture, plantations, devastated forest, 150 m elev. (83°15.26’W, 8°36.48’N) car net, 11.12.2012, leg. Schülke, M. & Grünberg, A. ( UIC); 1 male, 1 female, Rincón de Osa, Puntarenas Prov., Osa Pensinsula, Rd. Rincón> Chacarita (~ 83°20’W, 8°45’N), devastated forest plantations, 0–250 m elev., collected by car net, 10.12.2013, leg. M. Schülke & B. Grünberg (MSC, UIC); 2 males, 1 female, Cartago Prov, W Cachi, S side Cachi lake, road along lake shore, secondary forest, coffee plant., gardens (~ 83°49’W, 9°48’N), 1010–1040 m elev., collected by car net, 6.12.2013, leg. M. Schülke & B. Grünberg (MSC, UIC); 1 male, 3 females, Alajuela Prov., Rd. Colonia Puntarenas> Cano Negro (10°50’–53’N, 84°46’– 57’W), 40–90 m elev., fincas, meadows, forest remnants, collected by car net, 18.12.2013, leg Schülke & Grünberg (MSC, UIC); 3 females, Alajuela Prov., Rd. Colonia Puntarenas> Canalete> Bijagua (10°48’–50’N, 84°58’– 85°04’W), 100–400 m elev., fincas, meadows, forest remnants, collected by car net, 17.12.2013, leg Schülke & Grünberg (MSC, UIC); Ecuador: 1 specimen, Puerto Napo, rain forest, (77°43’W, 1°02’S), 18.7.1994, leg. Génier, F. ( KNHM); 1 specimen, Esmeraldas, Bilsa Biol. Stn., 500 m elev. (79°43’W, 0°2’N), flight intercept trap, 19.7.1998, leg. Hibbs, P. ( KNHM); Tiputini, Yasuni Res., in Eciton hamatum colony (76°24’W, 0°40.05’S), 7.7.1999, leg. Tishechkin, A. ( KNHM); French Guyana: 1 specimen, Cayenne (52°19’W, 4°53’N), light trap, 29.5.1997, leg. Ashe, J. ( KNHM); 1 specimen, Saül, under bark, (53°12’W, 3°37’N), 15.4.1999, leg. Berkov, A. ( KNHM); 1 specimen, Coralie (52°21.38’W, 4°30.41’N), 15.11.2011, leg. Struyve, T. ( UIC); Guadeloupe: 4 specimens, Gourbyre, (61°41’W, 15°59’N) (3 AMNH, 1 UIC); Guatemala: 1 specimen, Escuintla, Finca El Zapote, under bark, 730 m elev. (90°46’W, 14°17’N), 16.7.1948, leg. Mitchell, R. ( AMNH); Mexico: 1 specimen Teapa (92°57’W, 17°33’N) ( IRSB); 1 specimen, Oaxaca, 4.5 mi S Valle National, under bark, trop. hardwood, 500 m elev. (96°34’W, 17°1’N), 16.8.1973, Newton, A. ( FMNH); 5 specimens, Oaxaca, 4.3 mi S Valle National, under bark of hardwood, 16.8.1973, leg. Newton, A. ( FMNH); 1 specimen, Veracruz, Canyon, Rio Metlac (96°16’W, 19°11’N), Berlese, 27.2.1976, Newton, A. ( FMNH); 1 specimen, Balzapote (Veracruz), under bark, dead trees (96°22’W, 18°56’N), 7.7.1976, leg. Newton, A. ( FMNH); Panama: 1 specimens, San Francisco (80°58.36’W, 8°14.44’N), 15.6.1930, leg. Bierig, A. ( FMNH); 3 specimens, Gatun (79°45’W, 9°16’N), 15.6.1930, leg. Bierig, A. ( FMNH); 1 specimen, Canal Zone (- 79°34’W, 8°58’N), 1.7.1969, leg. Lawrence, J.F. ( MCZ); 4 specimens, Barro Colorado, under bark of hardwood, ferment. Stage (79°5’W, 9°09’N), 16.2.1976, leg. Newton, A.(3 FMNH, 1 UIC); 1 specimen, Barro Colorado, 27.2.1976, leg. Newton, A.( FMNH); 1 specimen, Cerro Azul, wet debris, small forest stream, 700 m elev. (79°25’W, 9°1’N), 21.2.1976, leg. Newton, A. ( FMNH); 1 specimen, Gatun, leaf litter (79°45’W, 9°16’N), 19.6.1976, leg. Newton, A. ( FMNH); 2 males, Barro Colorado, 16.2.1976, 27.2.1976, leg. A. Newton ( FMNH, UIC); 1 specimen, Chiriqui, Hornito, Finca la Suiza, 1220 m elev. (82°12’W, 8°39’N), flight intercept trap, 31.5.2000, leg. Howden, A. ( KNHM); Peru: 1 specimen, Puerto Maldonado (69°12’W, 12°37’S), flight intercept trap, 13.7.1989, leg. Leschen, R. ( KNHM); 1 specimen, San Jacinto, Campamento, 200 m elev. (75,51’W, 2°18’S), flight intercept trap, 5.7.1993, leg. Leschen, R. ( KNHM); 1 specimen, Madre de Dios, Manu National Park, Cocha Salvador, 310 m elev. (71°02’W, 12°2’S), flight intercept trap, 21.10.2001, leg. Brooks, R.W. ( KNHM); Puerto Rico: 1 specimen, Cayey (66°1’W, 18°07’N), 16.03.1917, leg. Hon, R.T.C. ( AMNH); Suriname: 1 specimen, Saramacca, 108 km SWS Zanderij (59°52.37’W, 5°13.37’N), under bark, 30 m elev., 9.3.1999, leg. Falin, Z.H. ( KNHM); Venezuela: 1 specimen, Rancho Grande, Prov. Aragua (67°41’W, 10°21’N), 15.6.1960 ( NHMW); 1 specimen, Aragua, Parque Nacional Henri Pittier, Ocumare km 36, La Trilla, deciduous forest, Brownea grandiflora , 300 m elev. (67°35’W, 10°14’N), fogging, 27.3.1990, leg. Davies, J. ( BMNH); 1 specimen, Sanaré, 17.4 km SE Yacumbu N.P., 1510 m elev. (69°34.34’W, 9°42.26’N), flight intercept trap, 1.6.1998, leg. Ashe, J. ( KNHM); 1 specimen, Carabobo, Mun. Bejuma, Cerro de Paja, 1500 m elev. (68°14’W, 10°16’N), 12.1.2007, leg. Brachat (VAC).

Diagnosis. T. filum Sharp, 1887 is characterised by its very minute size and the parallel and slender shape. It can be differentiated from the similar species T. verhaaghi n. sp. by the conspicuous colouration with dark head and abdomen and light red pronotum and elytra. It is differentiated from the similar T. zicsii n. sp. by the shorter elytra which are approximately quadrate, but distinctly longer than wide in T. zicsii . T. filum Sharp, 1887 seems to vary in its slender aspect. Some species seem be more slender than others. Slender specimens have a straighter aedeagus than specimens of normal shape, but intermediate specimens exist. Unfortunately, all five types specimens are females.

Description. Length: 1.30–1.45 mm. Colouration: clypeus, neck, pronotum and elytra orange; vertex of head and abdomen darker, brownish; posterior abdominal segments light reddish; legs and antennae yellow.

Head: 0.18 mm long, 0.25 mm wide; eyes large; slightly prominent; temples only one fifth of eye length; shortly narrowed to neck; neck as wide as width in front of eyes; sides in front of eyes shortly parallel; clypeus nearly semicircular; with very narrow margin; vertex depressed; without pair of swellings on vertex; only with indistinct impression at midline, without punctation; microsculpture dense and deep; meshes isodiametric; on vertex and central clypeus meshes slightly elongate; surface matte.

Antenna as long as head and half of pronotum combined; clavate; first and second antennomeres distinctly thicker than following four antennomeres; third antennomere conical; as long as width at apex; fourth to sixth antennomeres shorter; each shorter than width at apex; sixth to tenth antennomeres nearly twice as wide as long; tenth antennomere twice as wide as first antennomere; fifth to tenth antennomeres with short yellow bristles.

Pronotum: 0.20–0.21 mm long, 0.23–0.25 mm wide; widest at middle; nearly parallel in anterior half; anterior angles smoothly rounded; sides in posterior half convergent; narrowed to posterior angles in slightly concave curve; posterior margin as wide as two thirds of anterior margin; posterior angles obtuse; indistinct impression at posterior angles; slight impression at midline; central posterior margin with short bristles; without punctation; microsculpture as deep and dense as that on head; surface matte.

Elytra: 0.34–0.35 mm long, 0.29–0.30 mm wide; sides parallel; shoulders and posterior angles widely rounded; three indistinct carinae on each side of suture; without punctation; but with dense white scaly hairs; microsculpture as dense and deep as on pronotum; surface matte.

Abdomen without punctation; with similar white scaly hairs as those on elytra; in particular at posterior margin of each segment with transverse row of white scales; same dense and deep microsculpture as on fore-body; at basal impressions of segments slightly deeper; microsculpture more isodiametric than on fore-body.

Aedeagus curved in smooth curve between basal and apical lobe; ventral edge of apical lobe continuously curved; paramera similarly curved as central lobe; slightly longer than central lobe; at apex with transparent area with dense sensillae; at base with four to five sensillae; endophallus with thick basal bulb and long slender ductus; in some specimens central lobe straighter and with slight sinuate inner edge of apical lobe; then paramera also straighter.

Figures

FIGURES 1 – 3. Thoracophorus filum (1: from Belize, 1 ’: from Costa Rica); T. verhaaghi (2); T. zicsii (3); aedeagus in lateral aspect (A), antenna (B); scale bar: 0.1 mm.