Rasilinus tchambicus, Mazur, Milosz A., 2016

Mazur, Milosz A., 2016, A new genus and nine new species of Eugnomini (Coleoptera, Curculionidae) from New Caledonia, ZooKeys 554, pp. 87-118 : 90-91

Taxon classification Animalia Coleoptera Curculionidae

Rasilinus tchambicus sp. n. Figs 8, 17, 26, 35, 44, 70‒73, 84, 91, 98, 105, 112, 119, 125, 130, 135

Diagnosis.

One of the smallest members of new genus. The following combination of characters allows this species to be distinguished from its congeners: rostrum short and relatively thin with compare to its congeners, almost as long as head; pronotum wider than long; elytra weakly narrowed; minute tooth on fore and middle femora; apodemes much longer than aedegal pedon; tegmen with completely separated parameroid lobes.

Description.

Body length (lb)ca. 2.50 mm.

Body colour and vestiture (Fig. 8). Colour of body variable, from uniformly light brown to almost black. Elytra, pronotum and head usually dark brown, except for lighter rostrum and legs. Legs with three possible types of coloration: i) dark femora with lighter tibiae, ii) light femora (sometimes with darkening base) with darker tibiae (sometimes only apical part darkening), iii) femora and tibiae with the same colour. Rostrum and frons covered with two kinds of white scales: one suboval and recumbent and other elongate, protruding. Outer margin of tibiae with white, elongate, protruding scales. Elytral intervals with single line of protruding, elongate scales with variable colour, from dark on basal to bright on apical part of elytra. Entire surface of elytra covered with additional minute, hardly visible, short, piliform, recumbent scales.

Head, rostrum and antennae (Figs 26, 35, 44). Head elongate (hw/hl 1.30-1.45). Forehead flat. Eyes distinctly convex laterally; protruding above margin of head in lateral view; longer than half length of head (eyl/hl 0.63-0.70). Lateral margin of head narrowed from its base to hind margin of eyes. Vertex strongly scabrous, matt. Rostrum longer than width at apex (rl/arw 1.20-1.40), almost straight. Funicle much shorter than scape; first desmomere as long as 2 and 3 combined; desmomeres 4-7 subcircular, wider than long. Club ca. 2 × as long as its wide, longer than desmomeres 2-7.

Pronotum (Figs 17, 26). Wider than long (mpw/pl 1.15-1.27). Laterally slightly narrowed near base; strongly narrowed subapically. Apical margin straight; base slightly bisinuate. Surface distinctly rough, matt.

Elytra (Figs 17, 26). Elongate (el/mew 1.35-1.45), widest across humeral calli, weakly narrowed to apex. Striae with suboval, distinct punctures, at apical part of elytra punctures evanescent, forming indistinct line. Intervals glabrous, shining, weakly convex.

Legs (Figs 70-73, 84). Front and middle femora robust, with small teeth beyond middle; tibiae robust, front slightly sinuate, middle straight. Hind femora slightly narrowed beyond base; tibiae regularly curved, narrowed subapically. Claws regularly curved, distinctly broadened basally.

Abdomen (Fig. 91). Short, 1.08 × longer than wide. First suture obsolete at middle of length. Sutures between ventrites 2-5 distinct, depressed. Last ventrite trapezoidal, almost 2 × as wide as long, apical margin almost straight. Pygidium of male subquadrate; apical margin almost straight with numerous, elongate setae; lobed middle part small with single setae.

Male terminalia (Figs 105, 112, 119). Aedegal pedon shorter than apodemes; basal part sclerotised, slightly extended; lateral margins equilateral at basal half, from middle to apex distinctly narrowed; apex widely rounded. From lateral view distinctly, regularly curved with upturned apex. Endophallus not projecting outside pedon, internal structure not visible. Parameroid lobes of tegmen strongly elongate, thin, completely separated, of similar length to tegminal apodeme. Sternite VIII with bifurcate basal part; laterally flattened, apodeme slightly curved apically with thin apical keel; hemisternites on sternite IX subtriangular, clearly visible.

Female (Figs 98, 125, 130, 135). Similar to male in body shape but slightly larger. Elytra stout, widest beyond humeral calli, near middle. Apodeme of sternite VIII elongate, base bifurcate, irregular. Gonocoxite thin, elongate, more than 4 × as long as its wide; stylus minute with few setae. Spermatheca stout, distinctive curved. Abdominal tergite VIII more than 2 × wider than long; widely rounded apically; basally with slightly narrowed angles; surface with sparse punctation and few setae on apical margin.

Measurements.

Holotype, ♂: apw 0.45; arw 0.25; bew 1.10; bpw 0.60; el 1.50; eyl 0.25; frw 0.15; hl 0.35; hw 0.45; lb 2.45; mew 1.10; mith 0.15; mpw 0.60; mth 0.30; pl 0.50; ptbl 0.55; ptbmw 0.10; rl 0.35; scl 0.45.

Paratypes, ♂/♀: apw 0.45-0.50/0.55; arw 0.25-0.30/0.30; bew 1.10 –1.25/1.30– 1.35; bpw 0.60 –0.70/0.70– 0.75; el 1.50 –1.80/1.90– 2.00; eyl 0.25/0.25; frw 0.15/0.15; hl 0.35-0.40/0.35; hw 0.35 –0.45/0.45– 0.50; lb 2.45 –2.80/2.75– 2.90; mew 1.10 –1.25/1.35– 1.45; mith 0.15-0.20/0.20; mpw 0.60 –0.70/0.70– 0.75; mth 0.30-0.40/0.35; pl 0.50 –0.55/0.60– 0.65; ptbl 0.55-0.70/0.65; ptbmw 0.10-0.15/0.15; rl 0.35/0.40; scl 0.45-0.55/0.55.

Type material.

Holotype, ♂- -21.58536/165.79319, Col d’Amieu 500m (3,0 km to gate), 16.11.2008, leg. M. Wanat (MNHN).

Paratypes: 1♂ -21037.632'S 165045.830'E, Farino env. Les Grandes Fougéres, rainforest, netting, biting, 12.03.2008 467m, leg. R. Dobosz & T. Blaik; 5915/11630 (BMNH); 1♂,1♀ -21.61176/165.75406, Farino, Parc des Grandes Fougéres, 400m Camp de la Houe, 13.11.2008, leg. M. Wanat (MNHW); 1♀ -21035.1'S 16504', Col d’Amieu 490m (3,5 km from gate), 6-7.01.2007 (loc 3), leg. M. Wanat (MNHW); 1♂- -21.58536/165.79319, Col d’Amieu 500m, (3,0 km to gate), 16.11.2008, leg. M. Wanat (MNHW); 1♀-Col d’Amieu, Forestry Station, 18-21 Oct 1978, J.S. Dougdale; malaise trap; N.Z. Arthropod Collection NZAC, Private Bag 92170, Auckland, New Zealand (NZAC); 1♀ -21011'S 165016'E, Aoupinié 950-1000m, meteo st.-summit, 8.02.2004, leg. M. Wanat (MNHW); 1♀-Tchamba ( Wâo Uni), at day, rainforest, 1.04.2008, leg. T. Blaik (DBUO); 1♂ -21000.2'S/16504.6'E, Tchamba ( Wâo Uni), 16.01.2007 500-530m, forest, old northern road, leg. M. Wanat (MNHW); 1♂-Mt. Rembai, 700m, 18 Oct 1978, J.C. Watt; beating logging area at nigth; N.Z. Arthropod Collection NZAC, Private Bag 92170, Auckland, New Zealand (NZAC).

Etymology.

A toponymical adjective, after Tchamba, where some of the paratypes were collected.

Distribution.

New Caledonia (main island, north and south provinces).