Megacraspedus imparellus (Fischer von Roeslerstamm , 1843)

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 : 123-125

Megacraspedus imparellus (Fischer von Roeslerstamm, 1843)

Ypsolophus imparellus Fischer von Röslerstamm, 1843: 300, 303, pl. 100, figs 2 a–d [on plate as ‘imparella’].

Megacraspedus litovalvellus Junnilainen, in Junnilainen and Nupponen 2010: 10, figs. 16-17, 24, 30-31, syn. n.

Examined material.

Paratypes of M. litovalvellus : Russia. 2 ♂, S-Ural, Orenburg oblast, 20 km S Pokrovka village, Schibendy valley, 6-7.vi.1998, leg. K. & T. Nupponen (ZMUC); 4 ♂, same data, but 28.v.2004, leg. K. Nupponen (ZMUC); 1 ♂, same data, but 22.vi.1999, leg. T. & K. Nupponen; 1 ♂, same data, but 10.vi.2001, leg. K. Nupponen; 2 ♂, same data, but 28.v.2004 (RCKN). Non-type material. Austria. 1 ♂, Kärnten, Fraunstein, 9.v.1960, leg. K. Burmann (ZMUC); 7 ♂, Niederösterreich, Gramatneusiedl, Fürbachwiesen, 30.v.1979, leg. F. Kasy, genitalia slide GEL 1195 (NHMW, TLMF, ZMUC); 1 ♂, same data, but 27.v.1981 (ZMUC); 1 ♂, 1 ♀, Niederösterreich, Gramatneusiedl, 11.vi.1982, leg. E. Arenberger, genitalia slide GU 17/1479 ♀ Huemer (RCEA). Bulgaria. 1 ♂, 5 km N Sandanski, 270 m, 30.iv.2011, leg. Z. Tokár; 1 ♂, same data, but 5.v.2011, leg. Z. Tokár, genitalia prep. 12097 Z. Tokár (in glycerin) (all RCZT). Greece. 1 ♂, Thessalia, Olympos S, 30 km NW Karia, 1700 m, 10.vii.1990, leg. M. Fibiger; 1 ♂, same data, but 1850 m, 30.vii.1990 (all ZMUC); 1 ♂, 15 km W Kozani, Xerolimni, 21-23.v.2003, leg. J. Junnilainen, genitalia slide GU 16/1456 Huemer (RCJJ). Hungary. 1 ♂, Csákberény, Bucka-Hegy, 6.vi.1997, leg. Z. Tokár (ZMUC); 1 ♂, same data, but 21.v.2005, leg. Z. Tokár (RCZT); 1 ♀, same data, but 26.v.2011, leg. Z. Tokár (RCZT); 1 ♂, Mór-Gánt, 7.v.1995, leg. J. Liška (NMPC). Romania. 1 ♂, Muntii Apuseni, Cheile Turzii, 11.v.1991, leg. S. & Z. Kovács (RCKO). Slovakia. 1 ♀, Devínska Kobyla, 8.v.1992, leg. G. Pastoralis (ZMUC). Russia. 1 ♂, S Ural, Orenburg distr., Orsk, Guberlia village, 12-13.vii.2015, leg. H. Roweck & N. Savenkov;1 ♂, S Ural, Orenburg distr., Akbulak, Pokrovka village, 28-30.vi.2017, leg. H. Roweck & N. Savenkov (all ECKU); 1 ♂, Caucasus, Kabardino-Balkaria, Bezengi vill., 3.vi.1997, leg. I. & O. Kostjuk, genitalia prep. (in glycerin) (ZMKU).

Redescription.

Adult. Male (Figs 100, 102). Wingspan 12-16 mm. Segment 2 of labial palpus with long scale brush, light brown on outer, white mottled with brown on inner surface, white on lower and upper surface; segment 3 white with black tip. Antennal scape with pecten of 1-3 hairs; flagellum ringed black and light grey-brown. Head light grey-brown; thorax and tegula as forewing. Forewing bone white mottled with lighter and darker brown, especially in outer part of wing; black dots in fold at 2/5, and at 3/5 in middle of wing and at end of cell; an indistinct dark sub-costal dot at 1/3; scattered black scales forming an interrupted line along termen; fringes light grey. Hindwing light grey with concolorous fringes.

Female (Figure 101). Wingspan 10-12 mm. Antenna ringed black and white. Forewing slightly ellipsoid. Hindwing reduced in width and with an extended apex. Otherwise similar to male.

Variation.There is some variation in the amount of dark brown scales on the forewings. In some specimens they form a dark apical streak. Freshly emerged specimens are more greyish compared with specimens in collections. Specimens from Greece (Olympos) are slightly larger (wingspan 14-16 mm), slightly more broad-winged and with fewer dark scales on the forewing (thereby resembling M. leuca ) but the reduction of dark scales may be due to worn specimens.

Male genitalia (Figs 228-230). Uncus almost evenly rounded, about same length as width; gnathos hook moderately slender, gradually narrowing to apical point, approximately 1.5 times length of uncus, evenly curved from base to apex; tegumen with broad and shallow excavation of anterior margin, anteromedially small additional emargination; pedunculi small, suboval; valva extending slightly beyond tip of uncus, basally weakly inflated, digitate distal part weakly curved, tapered to slightly pointed apex; saccular area distinctly digitate, basally fused with valva, distal part separated; posterior margin of vinculum with shallow emargination, with weakly curved lateral hump, vincular sclerite sub-triangular; saccus broadly V-shaped, slightly shorter than valva, posterior margin weakly emarginated, with indistinctly sinusoid mediolateral humps, medial part with sclerotised ridge from posterior margin to middle of saccus, lateral sclerites about half length of maximum width of saccus; phallus with bulbous coecum, distal two-thirds moderately slender, with long dorsal sclerotisation, ductus ejaculatorius with long, 4 –5× contorted interior sclerotisation.

Female genitalia (Figure 289). Papilla analis medium-sized, apically rounded; apophysis posterior slender rod-like, approximately 2.3 mm long, weakly bent and widened at posterior third, with short, bifurcate posterior end; segment VIII approximately 0.5 mm long, lateroposterior part smoothly sclerotised, membranous ventromedial part with granulate microsculpture; subgenital plate with sub-triangular subostial sclerotisation, posteriorly extended into moderately short pointed sclerites, delimiting ostium bursae, anterior margin with rod-like edge connected with apophysis anterior, medially with nearly tubular projection; apophysis anterior approximately 0.9 mm, slender, rod-like, longer than segment VIII, posteriorly becoming small sclerotised zone weakly extended into segment VIII; colliculum short; ductus bursae short, broad, posterior part with granulate microsculpture, ductus seminalis originating near colliculum, broad, with granulate microsculpture; corpus bursae elongated suboval, weakly delimited from ductus bursae, entire length of ductus and corpus bursae approximately 2.2 mm; signum modertately small, transverse, spiny plate.

Diagnosis.

Megacraspedus imparellus is characterised by its light greyish brown forewings with three distinct black dots and an interrupted black line along termen. It normally has only a single pecten on the antennal scape, whereas the similar looking M. leuca (Figs 111-112) has several hairs on the antennal scape. It is furthermore similar to M. pacificus sp. n. (p 187) and M. majorella (p 124). The male genitalia are unmistakable due to the shape of the uncus, the gnathos hook, the saccular area and in particular the interior sclerotisation of the ductus ejaculatorius. The female genitalia differ from other species of Megacraspedus in particular in the granulate microsculpture of segment VIII, ductus bursae and ductus seminalis.

Molecular data.

BIN BOLD:ABW9450 (n = 2), BOLD:ADB7271 (n = 1), BOLD:ACB3182 (n = 1). Genetically variable species. The intraspecific divergence of the barcode region is large and reflected by 3 BINs with maximum divergence of 4.6% within all clusters. The minimum distance to the nearest neighbour M. attritellus is 9.2% (p-dist).

Distribution.

South-eastern Europe, with confirmed records from Austria, Bulgaria, Greece, Hungary, Russia (S. Ural, Caucasus), Romania, and Slovakia. A record from France ( Varenne and Nel 2014: 61) refers to M. quadristictus . For records from Germany see under Remarks. Records from Mongolia ( Piskunov 1979: 401-402) refer to M. leuca . Recorded from Italy (Toscana) by Mariani (1943: 174).

Biology.

Host plant and early stages are unknown. The type series of M. litovalvellus was collected at artificial light at night and by sweeping before sunset, from late May to early August on chalk steppe ( Junnilainen and Nupponen 2010). Other material was collected from late April to the first half of July, mostly in lowland localities, but in Greece at altitudes up to 1850 m.

Remarks.

Ypsolophus imparellus was described from two males and two females collected in June at Baden near Vienna, Austria (Fischer von Röslerstamm 1843). The excellent figures in the original description leave no doubt to the identity of this species. Megacraspedus litovalvellus was described from numerous specimens of both sexes collected in thesouthern Urals, Russia ( Junnilainen and Nupponen 2010). We examined several specimens and could not confirm the alleged diagnostic differences from M. imparellus stated in the original description. Thus M. litovalvellus is formally synonymised with M. imparellus (syn. n.). The intraspecific barcode divergence observed in this species is not supported by morphology.