Stenus perfectus nov.sp. (Figs 45, 74)

Type material: Holotype () and 7, 3 - paratypes: Taiwan: Nantou Hsien: Nankaoshan trail, Yuenhai Hut, 2350m, 4.V.1992, A. Smetana (T 112) . Paratypes: 2, 1: Nankaoshan, Tenchi Hut, 2800m, 6.V.1992, idem (T 13) ; 35, 36: ibidem, 2900m, 6.V.1992, idem (T 14); 13, 12: ibidem, 2895m, 7.V.1992, idem (T 119); 8, 12: 2.5 km SW Tenchi Hut, 2720m, 6, V.1992, idem (T 115).- HT and PTT in coll. Smetana (Ottawa), PTT also in cN, cT and in cP .

Description: About as in S. persubtilis nov.sp.

Length: 2.5-3.3 mm (forebody: 1.4-1.6mm).

PM of the HT: HW: 30; DE: 16; PW: 22; PL: 22.5; EW: 27; EL: 24; SL: 17.

Male: Metasternum shallowly impressed, coarsely and densely punctate, interstices smaller than half diameter of punctures. Anterior sternites simple, sternite 6 with a slightly finer punctation and pubescence medially, sternite 7 with finer and denser punctation and pubescence medially. Sternite 8 with a moderately shallow, moderately broad apical emargination (LS: ED= 47:3). Sternite 9 with short apicolateral teeth. Aedeagus (fig. 45), median lobe broadly subtruncate apically, expulsion hooks broad and short, separated; parameres longer than median lobe, with about 5-6 apical setae.

Female: Sternite 8 at posterior margin obtusely angled triangular, apex narrowly rounded. Valvifer with a short apicolateral tooth. Spermatheca (fig. 74) with a long and narrow infundibulum.

Median portion of frons distinctly exceeding the level of medial eye margins; pronotal and elytra impressions deep, punctation coarser than in S. persubtilis, elytral punctures becoming as large as median cross section of antennal segment 2; abdomen very densely punctate, interstices on tergite 7 distinctly smaller than half diameter of punctures.

Note: Amongst the PTT from T 114 there was found a monstrous male, which has broader, upwards bent paratergites and a very coarse, irregular elytral punctation. This may indicate that the broadness and position of the abdominal margination is a plastic character. This case also may be regarded as an example of atavism (as my friend Naomi suggests).

Comparative note: Also this new species has to be identified by examining the sexual characters.

Etymology: Because this species has a nice aedeagus I name it " perfectus " (Lat.= in good shape).