Elegia occultalis Plant, 2020

Plant, Colin W., Beshkov, Stoyan & Nahirnic, Ana, 2020, A new species of Elegia (Lepidoptera, Pyralidae, Phycitinae) from the Balkan Peninsula, Nota Lepidopterologica 43, pp. 311-318 : 311

Elegia occultalis Plant sp. nov.

Type material.

Holotype ♂ (Fig. 3 ). Albania, Ionian coast below Ilias, near Dhërmi, St. Theodor monastery, 140 m., 40°07 ’52” N, 19°39 ’21” E, 15.v.2017, S. Beshkov & A. Nahirnić leg., preserved in the C. W. Plant collection, which is bequeathed to the British Entomological and Natural History Society. Paratype ♀ (Fig. 4 ), North Macedonia, Vardar River Valley, above Demir Kapija town, 244 m, 41°22 ’58” N, 22°11 ’45” E, 13.vii.2019, Beshkov & A. Nahirnić leg., preserved in the C. W. Plant collection. Additional paratype material is 3♂♂1♀, same locality and data as holotype. One paratype male and one paratype female will be preserved in the National Museum of Natural History Sofia (NMNHS). The remaining paratype males are in the collection of C. W. Plant. Other material collected is in very poor condition and is excluded from the type series.

Diagnosis.

Elegia occultalis is most likely to be confused with E. atrifasciella in the European fauna and is probably not separable in the adult stage without recourse to examination of genitalia. The male genitalia are typical of the genus, with valva and associated digitus similar to Elegia atrifasciella , but the apices of the labides are rounded in both atrifasciella and similella , whilst acute in E. occultalis . Elegia fallax , also with acute labides, has these spines long and usually reaching as far as the apex of the gnathos. The female genitalia exhibit a cleft lateral lamella, and may not be distinguishable from those of E. atrifasciella . The moth should be readily distinguished from E. similella because it lacks the bright white wing fascia of the latter species. If it should transpire, as a result of further research, that the range of the new species overlaps geographically with that of E. iozona , then confusion between these two taxa is also likely to require genitalia examination for resolution. Separation from two recently described Turkish species is achievable by comparison of the shape of the gnathos, which is round in E. occultalis , spoon-shaped in feminina and ovoid, with an angular apex in saecula .

Description of the new species.

Holotype male (Fig. 3 ). Forewing length of set specimen 10 mm, measured from wing tip (including cilia) to thoracic wall. Head, including frons, vertex and entire antennae grey-scaled. Antennal scape modified, flattened laterally and with scales on dorsal aspect forming a smooth extension. Basal 5 segments of antennal flagellum separately modified, with enlarged scales front and rear curving dorsally to form, and enclose a concave depression ( “knot”) on the dorsal surface - internally black in colour. Labial palps grey-scaled, but with occasional darker scales and segment 3 (apical segment) darker than basal segments. Thorax, including tegulae and scutellum, grey-scaled - concolourous with basal area of forewing. Forewing with venation as in other Elegia species. Upper side with orbicular, reniform and claviform stigmata obscure. No basal spot. Wing grey-scaled in basal area (basal 2.5 mm), with some scales minutely irrorate whitish, beyond which is a black band, equating to the ante-median fascia, extending from costa to dorsum, approximately 1 mm wide at the costa and 1.5 mm wide at dorsum. Outer edge of this black band more or less straight and more or less meeting costa at 90 degrees; inner edge less sharply defined, bulging basad at mid-point where a small, almost indiscernible area of grey scales with white apices affects the central 50% of the wing, centred on the median fold. Distal edge of the black band is defined by a 0.5 mm wide band of whitish grey scales, poorly-defined on the distal edge, but macroscopically perceived as a narrow, dirty white band beyond the black band. Remaining (distal) area of forewing upper side grey-scaled with markings largely obfuscated, except for dentate subterminal line picked out by darker, blackish scales. Terminal line defined by 4 or 5 small dark spots. Cilia long, alternating grey and darker grey. Hind wing upper-side uniformly grey except for slightly darkened terminal line, most obvious in the apical region. Cilia uniformly pale grey with darker grey patches forming a grey sub-basal line. Forewing under-side dark grey, cilia concolorous except for very fine light basal line and darker grey sub-basal line. Hind wing underside whitish grey, with a narrow darker terminal line, long veins darkened, cilia with narrow pale basal line and greyish subterminal band. Abdomen grey-scaled, legs concolourous. Genitalia (Fig. 5 ): slide number CP/1997/20. Labides acute and with terminal spines not extending as far as the apex of the gnathos. Gnathos terminating in a dorso-ventrally flattened area, more or less round in shape.

Paratype female (Fig. 4 ). Forewing length of set specimen 10 mm (measured as mentioned above). Identical to male, except for antennal modifications, which are lacking, and in that the outer band of whitish scales beyond the black ante-median fascia is better defined and more distinct to the unaided human eye. Additionally, the darkish subterminal line is defined on its distal edge by a narrow zone of whitish grey scales. Genitalia (Fig. 6 ): slide number CP/1998/20, remarkably similar to that of E. atrifasciella with cleft lateral lamella antevaginalis.

Variation within the type series.

There is minimal variation in the type series in the width and definition of the various bands on the forewing, presumably resulting in large part from "wear and tear". Males display minor variation in the gnathos, with some specimens bearing an indentation in the posterior tip. The range of variation observed is shown in Fig. 5d, e . However, the overall shape of the gnathos is constant.

Etymology.

The name occultalis is derived from the Latin adjective occulta meaning “secretive”, in feminine form and in combination with the suffix “-alis” applied, historically, to many Pyralidae species. The name is a reflection of the supposition that the new species has been hidden amongst the other Elegia species.

Figures

Figure 3. Elegia occultalis Plant, sp. nov. Holotype male, Albania, 15. v. 2017. Photography by Graeme J. Smith (UK).

Figure 4. Elegia occultalis Plant, sp. nov. Paratype female, North Macedonia, 13. vii. 2019. Photography by Graeme J. Smith (UK). The slight yellowing of the forewings is a consequence of the specimen becoming " greasy "; in life, the wing colour is identical to that of the male.

Figure 5. genitalia of holotype male Elegia occultalis Plant, sp. nov. a. overall genital capsule, b. phallus (not everted) and c. culcita. d-e. variation in the gnathos in two different specimens from the type series. In euparal on glass slide, CP / 1997 / 20, images captured and photo stacked by Peter Hall (Worcester, UK).

Figure 6. Elegia occultalis Plant, sp. nov. genitalia of paratype female. In euparal on glass slide, CP / 1998 / 20, by CWP. Images captured and photo stacked by Peter Hall (Worcester, UK).