Megacraspedus peslieri Huemer & Karsholt, 2018

Huemer, Peter, 2023, The female of Megacraspedus peslieri Huemer & Karsholt, 2018 (Lepidoptera, Gelechiidae), a new case of brachyptery in alpine Lepidoptera, Alpine Entomology 7, pp. 37-44 : 37

Megacraspedus peslieri Huemer & Karsholt, 2018

Material examined.

24♂, 2♀: Italy , prov. Torino, PN Orsiera - Rocciavré, Fenestrelle, Forte Serre Marie, 1830 m a.s.l., 45°02'57"N, 07°03'03"E, 21.8.2022, leg. Huemer (DNA Barcodes TLMF Lep 33718-33721; gen. slide P. Huemer GEL 1351♀; 1♂: Italy, prov. Torino , PN Orsiera - Rocciavré, Villaretto , Gran Faetto , Colletto, 1445 m a.s.l., 45°00'28"N, 07°08'28"E, 21.9.2019, leg. Huemer (all coll. Tiroler Landesmuseum Ferdinandeum, Innsbruck, Austria).

Description

(Figs 2 - 6 ). For a detailed description of the male including the male genitalia see Huemer and Karsholt (2018). Males (Figs 2 , 4 ) are more variable in size than originally described, with a forewing length ranging from 7.2-9.0 mm; furthermore, the cream-coloured dorsum is clearly separated from the remaining and predominantly brownish mottled part of the forewing with mainly cream-coloured veins in fresh samples, and the third segment of the labial palpus is entirely cream-white.

Female (Figs 3 , 5 - 6 ). Segment 2 of labial palpus with long scale brush, dark brown on outer and lower surface, cream-white mottled with brown on inner surface, cream-white on upper surface; segment 3 cream-white. Antennal scape without pecten; flagellum cream-white, annulated with light brown. Head and thorax cream-white with some light brown mottling, particularly on tegula. Forewing length 3.8-4.4 mm. Forewing distinctly reduced, shorter than abdomen, with strongly convex dorsal margin, cream-white ground colour intensely mottled with light brown; with few darker brown spots in middle and at apex; fringes reduced to group of very long, bristle-like hairs around apex. Hindwing reduced to minute sub-oval flap, with narrow long scales near apex, frenulum with one to two well-developed bristles.

The male and female are easily distinguished by the largely reduced wings of the female with an indistinct wing pattern compared to the male (Figs 2 - 5 ).

Female genitalia (Figs 7 - 8 ). Papilla analis large, weakly sclerotized, apically evenly rounded, slightly longer than segment VIII, lateral part with anteriorly widened sclerotized area; apophysis posterioris rod-like, short, about 1.65 mm long, apex slightly widened, rounded, anteriorly membranous intersegmental zone; segment VIII about 0.6 mm long, smooth, laterally sclerotized, medially membranous with microsculpture in anterior and posterior parts; subgenital plate without specialized sclerotizations, anterior edge with short sinusoid projection delimiting ostium bursae; apophysis anterioris rod-like, about as long as segment VIII; colliculum about 1/2 length of apophysis anterioris, wrinkled, with small sclerotization anteriorly; ductus bursae slender, about 1.5 mm long; corpus bursae clearly delimited, about as long as ductus bursae, slender; signum moderately small, laterally oblong spiny plate, with about two dozen small to strong spines.

Remarks.

The female genitalia support the unique position of M. peslieri and clearly differ from all other species groups particularly by the simple structure of the subgenital plate without specialized sclerotizations in combination with the peculiar signum. Furthermore, the distally rounded papilla analis combined with a short apophysis posterioris is rarely observed in other species.

Biology.

The species is on the wing late in the season, from late August to the last third of September and active even at low temperatures of ca 6 °C. Both males and females of M. peslieri were observed sitting on grass stems or on other herbaceous plants and detected by illumination with a headlamp in the first two to three hours of the night. Simultaneously, males were attracted to UV light in large numbers.

Distribution.

Only known from few localities in the Pyrenees (France, Spain) and the Cottian Alps (Italy) ( Huemer and Wieser 2020).

Habitat

(Fig. 9 ). The habitat in the Cottian Alps is predominated by xeromontanous grassland intermixed with rock formations on siliceous soil, at montane elevations from approximately 1400 to 1800 m a.s.l. In the Pyrenees the species was collected at lower altitudes from ca 250 to 900 m a.s.l.

Figures

Figure 2. Megacraspedus peslieri, male in natural resting position (Italy, Alpi Cozie).

Figure 3. Megacraspedus peslieri, female in natural resting position (Italy, Alpi Cozie).

Figure 4. Megacraspedus peslieri, set male specimen (scale bar: 3 mm).

Figure 5. Megacraspedus peslieri, set female specimen (scale bar: 2 mm).

Figure 6. Megacraspedus peslieri, details of female hindwing (marked with red arrow) (scale bar: 0.5 mm).

Figure 7. Megacraspedus peslieri, female genitalia (scale bar: 0.5 mm).

Figure 8. Megacraspedus peslieri, female corpus bursae with signum enlarged. (scale bar: 0.1 mm).

Figure 9. Habitat of Megacraspedus peslieri in the Cottian Alps, above Fenestrelle.