Megacraspedus leuca (Filipjev, 1929)

Huemer, Peter & Karsholt, Ole, 2018, Revision of the genus Megacraspedus Zeller, 1839, a challenging taxonomic tightrope of species delimitation (Lepidoptera, Gelechiidae), ZooKeys 800, pp. 1-278 : 135-137

Megacraspedus leuca (Filipjev, 1929)

Nothris leuca Filipjev, 1929: 9, pl. 2a, fig. 3.

Megacraspedus kaszabianus Povolný, 1982: 193, figs 1-2, syn. n.

Examined material.

Paratypes of M. kaszabianus . Mongolia. 1 ♂, Gobi Altaj aimak, Chasat chajrchan ul mts, cca. 20 km S Somon Zargalan, 2400 m, 15.vii.1966, leg. Z. Kaszab; 1 ♂, Südgobi aimak, Gurban Sajchan ul, 15 km S Dalanzadgad, 1750 m, 13.vi.1967, leg. Z. Kaszab; 1 ♂, 1 ♀, Südgobi aimak, Somon Bulgan Talyn bulag, 1350 m, 5.vii.1967, genitalia slides GU 16/1446 ♂ Huemer, GU 16/1447 ♀ Huemer, leg. Z. Kaszab (HNHM). Non-type material. Russia. 1 ♂ Alai mts, Kuraisk hrebet, 2300 m, 13.vii.2001, leg. K. Nupponen, genitalia slide no. 3/21.X.2008 K. Nupponen (RCKN); 2 ♂, Altai rep., 15 km S Kosh-Agach, Thuja steppe, 1800 m, 10.viii.2000, leg. A. Bidzilya (ZMUC); 4 ♂, Altai rep., 6.5 km SW Kosh-Agach, Kurai env., 1550 m, 9-10.vii.2014, leg. J. Šumpich, genitalia slide GU 16/1408 ♂ Huemer (NMPC, TLMF); 19 ♂, Altai rep., 10 km NE Kosh-Agach, Kurai mts, Range valley of Tabozhok river, 2100 m, 2-4. viii.2016, leg. P. Huemer & B. Wiesmair; 1 ♂, Altai rep., 17 km NNE Kokorya village, Chikhacheva mts range, Talduair Mt., valley of Sajlyugem river, 30. vii– 2.viii.2016, leg. P. Huemer & B. Wiesmair; 2 ♂, Altai rep., Aktasch env., 17. vi– 2.vii.2009, leg. B. Schacht (all TLMF); 4 ♂, Tuva rep., 52°04'N, 94°22'E, Ust-Uljuk, steppe hills, 670 m, 3-5.vi.1995, leg. J. Jalava & J. Kullberg (MZH); 26 ♂, Tuva rep., 50°01'N, 95°03'E, Lake Tere Khol, sand dunes, 1150 m, 9-12.vi.1995, leg. J. Jalava & J. Kullberg (MZH, ZMUC); 8 ♂, 1 ♀, Tuva rep., 50°16'N, 94°54'E, ca. 25 km W Erzin, steppe/stony slopes, 1250 m, 7-11.vi.1995, leg. J. Jalava & J. Kullberg (MZH); 18 ♂, Tuva rep., 50°44'N, 93°08'E, E Tannu-Ola mts, Irbitei r., stony steppe slopes, 1000 m, 13-16.vi.1995, leg. J. Jalava & J. Kullberg (MZH); 1 ♂, Tuva rep., 50°45'N, 94°29'E, E Tannu-Ola mts, 5 km ENE Khol-Oozha, steppe slopes, 1000 m, 13-16.vi.1995, leg. J. Jalava & J. Kullberg (MZH).

Redescription.

Adult. Male (Figure 111). Wingspan 15-18 mm. Segment 2 of labial palpus with sub-rectangular scale brush longer than segment 3, blackish brown mottled with white, especially on upper surface; segment 3 about two-thirds length of segment 2, white mottled with black. Antennal scape with pecten of several hairs; flagellum light brown, indistinctly ringed with black. Head, thorax and tegula whitish mottled with light brown. Forewing cream whitish, mottled with brownish- or blackish-tipped scales; indistinct blackish blown spots in yellow-white fold and at 2/3 and 3/4 in middle of wing; fringes whitish grey with two grey fringe lines. Hindwing light grey with concolorous fringes.

Female (Figure 112). Wingspan 15 mm. Otherwise similar to male.

Variation. The amount of brownish- or blackish-tipped scales of the forewing varies; they are normally scattered over the wing but can also form lines along the veins. The blackish brown dots on the forewing can be more or less distinct. One specimen (in good condition) is almost without dark scales.

Male genitalia (Figure 237). Uncus large, sub-square, apical corners rounded, apical edge straight to weakly emarginated; gnathos hook evenly slender, apically pointed, almost twice length of uncus, bent at right angles at about one-quarter; anterior margin of tegumen with broad and shallow U-shaped emargination, anteromedially small additional emargination; pedunculi small, suboval; valva stout, extending slightly beyond base of uncus, basally weakly inflated, digitate distal part weakly tapered to slightly pointed apex; saccular area densely covered with setae, longitudinal ridge present, without separated sacculus; posterior margin of vinculum shallow medial emargination, without distinct lateral humps, vincular sclerite elongated sub-triangular, with sclerotised posterior edge; saccus prominent, longer than valva, U-shaped, ratio maximum width to length approximately 0.7, posterior margin with broadly rounded shallow projections, separated by small incision, medial part with long sclerotised ridge from posterior margin to apex of saccus, lateral sclerites approximately 0.8 times length of maximum width of saccus, with distinctly bulged apex; phallus with weakly inflated coecum, about two times wider than distal part, distal part more than twice length of coecum, sclerotised dorsal ridge with one to five small teeth.

Female genitalia (Figure 292). Papilla analis weakly sclerotised, moderately small, apically rounded; apophysis posterior slender rod-like, short, slightly longer than apophysis anterior, posterior end with small transverse sclerotised zone; segment VIII very short, laterally strongly sclerotised, medially largely membranous; anterior edge of segment VIII laterally rod-like, connected with apophysis anterior, subgenital plate reduced, ostium bursae without bordering sclerotisations; apophysis anterior rod-like, almost five times length of segment VIII, posteriorly broadly connected with segment VIII by sclerotised band; colliculum short, ring-shaped; ductus bursae slender, weakly widening to hardly delimited, oblong corpus bursae; signum reduced.

Diagnosis.

Megacraspedus leuca is characterised by having the antennal scape with a pecten of several hairs, and by the having the cream whitish grey forewings mottled with brownish- or blackish-tipped scales. It resembles M. multispinella (Figs 103-104), which is smaller and has greyish white forewings with black scales along the apical margins. It is furthermore similar to M. imparellus (p 130), M. orenburgensis (p 144), and M. attritellus (p 138). The male genitalia are unmistakable and in particular the prominent, long and slender U-shaped saccus is unique in Megacraspedus . The female genitalia are characterised by several unique structures such as the short segment VIII with a membranous medial part, the comparatively very long apophysis anterior, and the absence of a signum.

Molecular data.

BIN BOLD:ACB3260 (n = 10). The intraspecific divergence of the barcode region is low with mean 0.03% and maximum divergence of 0.2%. The distance to the nearest neighbour M. skulei is 6.6% (p-dist).

Distribution.

Asian part of Russia, Mongolia.

Biology.

Host plant and early stages are unknown. Bidzilya (2002: 64) collected adults in numbers at artificial light placed among tussocks of Achnatherum splendens (Trin.) Nevski (= Stipa splendens Trin.). M. leuca is by far the most common species of the genus in Central Asia, inhabiting a wide range of different steppe habitats. According to Povolný (1982) it was collected from June to August in grass-, sand- and salt steppes at altitudes of between 1000 and 2400 m. Adults are easily attracted to articificial light (PH, pers. obs.).

Remarks.

Nothris leuca was described from one male collected at Munku-Sardyk (= Mönkh-Saridak) in the Sajan Mountains at the border between Russia and Mongolia (Filipjev 1929). The holotype in ZISP was studied and figured by Junnilainen and Nupponen (2010: 11).

Megacraspedus kaszabianus was described from several hundred males collected in Mongolia by Z. Kaszab ( Povolný 1982). We have been able to examine paratypes, which fully agree with M. leuca in every detail. We therefore formally synonymise M. kaszabianus with M. leuca (syn. n.).