Stenus mithracifer, Puthz, 2011

Puthz, V, 2011, On the Stenus LATREILLE 1797 from Taiwan with spotted elytra including remarks on the S. gestroi-group (Coleoptera, Staphylinidae) (316 Contribution to the Knowledge of Steninae), Linzer biologische Beiträge 43 (1), pp. 565-596 : 576-577

Stenus mithracifer nov.sp. ( Figs 20 , 26, 27 , 108 )

T y p e m a t e r i a l: Holotype () and 2 - paratypes: TAIWAN: Taoyuan-Taipei Hsien: near Mt. Lalashan , 24.VII.1978, Y. Shibata . Paratypes: 2: ibidem, W. Suzuki; 1, 1: ibidem, 25.VIII.1978, Y. Shibata; 2: Taoyuan Hsien: near Lalashan , 1., 2.VIII.1985, Y. Shibata ; 1: ibidem, 5.V.1978, T. Kobayashi.- HT and PTT in coll. Shibata, PTT also in cP.

D e s c r i p t i o n: Micropterous, black with a faint brownish hue, each elytron with an oval orange spot in about posterolateral half (fig. 26), moderately shiny, forebody coarsely and densely punctate, abdomen moderately coarsely (anteriorly) to finely and moderately sparsely (posteriorly) punctate; pubescence short, recumbent. Antennae yellowish, club slightly infuscate. Maxillary palpi yelliowish, segment 3 slightly infuscate. Paraglossae oval. Legs reddish brown. Clypeus black, labrum dark brown, moderately densely pubescent.

Length: 5.0-6.0 mm (forebody: 2.4-2.7 mm).

PM of the HT: HW: 40; DE: 23; PW: 30; PL: 36; EW: 35; EL: 39; SL: 27; SpL: 13.

M a l e: Legs simple. Metatsternum slightly impressed medially, moderately coarsely and moderately densely punctate throughout. Anterior sternites simple, sternite 7 finely and densely punctate in posterior middle. Sternite apically 8 with a moderately broad notch about one twentieth as long as the sternite. Sternite 9 with an acute tooth apicola- terally. Tergite 10 broadly rounded. Aedeagus (fig. 108), apical portion of median lobe broadly rounded with an apical area of densely arranged short setae, a slightly stronger sclerotized help-mechanism for expulsion (no delimited expulsion clasp!) and a broad tubous internal sac; parameres very long, much exceeding the median lobe, with about 21 apical setae.

F e m a l e: Sternite 8 rounded apically with a slight but distinct median projection. Valvifer acute apicolaterally. Tergite 10 rounded apically. Spermatheca (fig. 20) with a long and narrow infundibulum.

Head broader than elytra, frons braod with two broad longitudinal furrows, median portion about as broad as each of the lateral portions, broadly elevated, nearly extending to the level of dorsal eye margins; punctuation coarse and, except on the median portion, very dense, diameter of punctures as large as largest cross section of antennal segment 3, interstices much smaller than half diameter of punctures becoming up to twice as large as punctures on the actual middle. Antennae very slender, about the last two segments extend beyond the posterior margin of the pronotum when reflexed, penultimate segments twice as long as broad. Pronotum distinctly longer than braod, broadest in about middle, straightly narrowed anteriorly, moderately concavely narrowed posteriorly; a broad transverse impression can be seen laterally; punctuation about as on frons, few very small impunctate areas (slightly larger than one puncture) in the middle. Elytra subtrapezoid, narrower than head, longer than broad, shoulders oblique, sides nearly straightly widened, restricted in posterior fifth, posterior margin deeply emarginated; sutural and humeral impressions shallow; punctuation still coarser than on pronotum, very dense, punctures about as large as apical cross section of antennal segment 2; orange spot about one third as long as one elytron. Abdomen cylindric, line-like margined (without paratergites), basal furrows of anterior segments very deep, tergite 7 with a distinct membranous fringe apically; punctures on tergite 4 as large or slightly larger than one eye facet near dorsal eye margin, interstices nearly twice as large as punctures; punctures on tergite 7 distinctly smaller than one dorsal eye facet, interstices three times and more as large as punctures; tergite 10 finely and sparsely punctate. Legs very slender, metatarsi more than two thirds as long as metatibiae (35: 50), segment 1 slightly shorter than the three following segments combined, twice as long as the last segment; segment 4 deeply bilobed. The whole body is distinctly reticulate.

C o m p a r a t i v e n o t e s S. mithracifer nov.sp. belongs to the " S. tenuimargo - group" (s. b.), where it is the sister species of S. miwai BERNHAUER and may be distinguished by the abdominal punctuation, which is much finer and sparser, any by the sexual characters.

E t y m o l o g y:" mithracifer " (Lat.) = dressed with gems.

Figures

Figs 11-25: Pronotum (11, 12), expulsion hook (13), dorsal aspect of abdominal segments 6 and 7 (14, 15), spermatheca (16, 20-25), lateral portion of median lobe (17), ventral aspect of a detail of the anterior portion of median lobe (18, 19) of Stenus gestroi FAUVEL (11, Carin Cheba; 12, Arni Gad; 13, 17, Tokara Is.; 14, Nanshanchi; 15, Peiyuan), S. electrigemmeus nov.sp. (16, PT 152; 18, HT), S. electrigemmatus nov.sp. (19, HT), S. mithracifer nov.sp. (20, PT), S. miwai BERNHAUER (21, Mt. Karapin), S. virgula FAUVEL (22, Lebong), S. bicolon posticus FAUVEL (23, Malaysia: Bringchang), S. stigmosus nov.sp. (24, PT, T 3) and S. stigmifer nov.sp. (25, PT, Kaolin).

Figs 26-45: Elytra (26, 28, 30, 31, 33-43), dorsal and lateral aspect of abdominal segments (27, 29, 32, 44) and ventral aspect of abdominal segments 6 and 7 (45) of Stenus mithracifer nov.sp. (26, HT; 27, PT), S. electrigemmeus nov.sp. (28, HT; 29, PT), S. electrigemmatus nov.sp. (30, HT), S. electristigma nov.sp. (31, HT; 32, PT), S. shibatai nov.sp. (33, HT), S. shibataiellus nov.sp. (34, HT), S. shibataianus nov.sp. (35, HT), S. stigmifer nov.sp. (36, HT; 37, PT, T 24), S. bilunatus PUTHZ (38, T 86), S. bigemmatus nov.sp. (39, HT), S. bigemmosus nov.sp. (40, HT), S. bilunatior nov.sp. (41, PT, T 127), S. bilunatoides nov.sp. (42, PT, T 155), S. bistigmosus nov.sp. (43, HT), S. miwai BERNHAUER (44, Henglou), S. bicolon SHARP (45, Tengchih).

Figs 108-121: Ventral aspect of aedeagus/apical portion oft the median lobe (108-111, 114, 116- 119), spermatheca (112, 113, 15), apical portion of valvifer (120, 121) of Stenus mithracifer nov.sp. (108, HT), S. shibatai nov.sp. (109, PT), S. shibataianus nov.sp. (110, HT; 112, 120, PTT), S. shibataiellus nov sp. (111, HT), S. electristigma nov.sp. (113, 117, 121, PTT), S. cirricinctus PUTHZ (14, HT), S. arisanus CAMERON (115, Alishan), S. electrigemmeus nov.sp. (116, HT), S. stigmosus nov.sp. (116, PT), S. stigmifer nov.sp. (119, HT). Scale bar = 0.1 mm (108 = 109-115, 120, 121; 116 = 117-119).