Agrotis mayrorum, Ronkay & Huemer, 2018

Ronkay, Laszlo & Huemer, Peter, 2018, Agrotis fatidica (Huebner, 1824) species-group revisited, with description of two new species from the Alps and the Pyrenees (Lepidoptera, Noctuidae), Nota Lepidopterologica 41 (1), pp. 145-179 : 145

Agrotis mayrorum sp. n. Figs 21-24 , 25-32 ; Gen. figs 4 -7 , 17

Holotype.

Male, Italy, Prov. Cuneo, Alpi Cozie, Demonte NW, Colle Valcavera NE, 2420 m, 17.VIII.2012, leg. P. Huemer; DNA Barcode ID TLMF Lep 08820 (TLMF).

Paratypes.

Italy. 15 males, Prov. Cuneo, Alpi Cozie, Demonte NW, Colle Valcavera NE, 2420 m, 17.viii.2012, leg. P. Huemer; slide No. RL11122m; DNA Barcode IDs TLMF Lep 08647, TLMF Lep 08648, TLMF Lep 08819 (TLMF); 2 males, Prov. Cuneo, Alpi Cozie, Demonte NW, Colle Valcavera, 2450 m, N 44°22,9', E 07°07,2', 16.viii.2013, leg. Mayr (RCTM); 10 males, Prov. Cuneo, Alpi Cozie, Demonte NW, Gias Valcavera, 2050 m, N 44°22,6', E 07°08,2', 17.viii.2012, leg. Mayr; slide No. P. Huemer N 1591♂ (RCTM; TLMF); 2 males, Prov. Cuneo, Alpi Cozie, Demonte NW, Gias Valcavera, 2050 m, N 44°22,6', E 07°08,2', 16.viii.2013, leg. Mayr (RCTM); 4 males, Prov. Cuneo, Alpi Cozie, Demonte NW, Gias Valcavera, 2050 m, N 44°22,6', E 07°08,2', 28.vii.2015, leg. Mayr (RCTM). France. 1 male, Alpes Maritimes, Colle di Tenda, Fort Central Alpi Marittimi, 1870 m, 6.viii.1996, leg. A. Otter; slide No. RL11123m (TLMF); 1 female, Alpes Maritimes, Vens, 14.viii.1954, slide No. RL11780f (TLMF); 2 males, Alpes Maritimes, Col de la Bonette, 2100 m, 14.viii.1977, leg. F. Dujardin (TLMF); 2 males, Alpes Maritimes, Col de la Bonette, 2100 m, 21.viii.1977, leg. F. Dujardin (TLMF); 2 males, Alpes Maritimes, Col de la Bonette, 2800 m, 27.viii.1978, leg. F. Dujardin (TLMF); 2 males, Basses-Alpes, Larche, Harold Powell, 1-27.viii.1918, ex coll. Oberthür, slide No. RL11513m (BMNH); 1 male, Larche, ex coll. Bellier, slide No. RL11514m (BMNH); 1 male, Basses Alpes, Larche, Aout 1897, 3 Coulet, coll. Oberthür (BMNH); 2 males, "Larche, ex coll. Oberthür” (BMNH); 1 male, Hautes Alpes, Col de la Cayolle, 2326 m, 29.-30.vii.2009, leg. B. Skule; DNA Barcode ID TLMF Lep 16460 (RCBS); 1 male, Hautes Alpes, col de Vars, 2115 m, 31.vii.-7.viii.1933, leg. Ch. Boursin (BMNH); 1 male, Hautes Alpes, St. Veran, viii.1929, coll. Stempffer (ZMHU); 2 males, Basses Alpes, Col de Restefond, 15.viii.1990, leg. E. von Mentzer, slide No. 13098; NRMS TOBI 00194, 00198 (NRMS).

Etymology.

Named in honour of Marlies and Toni Mayr (Feldkirch, Austria) who collected the new species in companionship with Peter Huemer and recognized its differing morphology.

Diagnosis.

The new species can be distinguished from the pale forms of A. fatidica by its lighter appearance, which is the consequence of the generally paler, milky whitish hindwings. The hindwings of the new species have only sparse, light greyish-brown irroration along the costal margin and narrow and discontinuous submarginal stripe while the narrow marginal ribbon along the variably dark, often obsolescent or deleted terminal line is whitish, as are the hindwing cilia. The discal lunule is just a fine shadow on the upperside, and the veins have a fine brownish covering. The underside of the hindwing lacks the transverse stripe (only a diffuse patch at costal margin may be present), the costal area is paler, suffused with brown, and the discal spot is rather weak, usually with a whitish inner liner on the crossvein of the cell.

By contrast, in A. fatidica , the typical specimens have dark greyish-brown suffused hindwings, with variably strongly diluted inner area, and a more prominently marked discal spot. Specimens with paler hindwings are relatively rare, but even they have broader and darker marginal field, extending in almost every specimen to the terminal line, and the discal lunule is stronger and darker, more contrasting than in A. mayrorum . The hindwing underside of A. fatidica is generally darker, usually with a broad and diffuse transverse stripe and a darker discal spot; these elements of the underside pattern are more strongly marked even in the palest A. fatidica specimens than in the new species. Another typical feature of A. mayrorum is the diffuse or obsolete postmedial line, which is less curved at the costa than in A. fatidica and A. mazeli . The dark dots tracking the fine terminal line are less prominent on the upperside than in the other two close relatives, and are almost invisible on the underside, only the thin terminal line is clearly marked. The detailed comparison of A. mayrorum and A. mazeli is given under the diagnosis of the latter species.

Agrotis mayrorum can easily be distinguished from A. proverai by the external features of the moths, being on average remarkably larger, with a more robust body and distinctly broader forewings, paler and more greyish ground colour and more prominent tessellate wing pattern, having characteristically prominent pale lining of the cubital vein and the much paler, never strongly dark filled reniform stigma. The other elements of the wing pattern (e.g. the shape and distinctness of the postmedial line, its distance from the reniform stigma, the shape and size of the arrowhead-spots, etc.) sometimes overlap with the condition in A. proverai so are unreliable, although they are usually different in the majority of the specimens.

The frontal prominence of A. mayrorum , although somewhat variable in shape and size, is less thick and more rounded or drop-shaped than the taller, more protruding frontal prominence of A. proverai .

The diagnostic features of the male genitalia of A. mayrorum are the long and slender valva (comparatively the longest and narrowest within the European species of the fatidica complex), with a less dilated distal section and only a slightly convex distal dorsal margin and reduced membranous ventral edge along the sacculus; the most often elongated-triangular cucullus with pointed apex; the short and broad clasper, which is distinctly shorter than in A. mazeli and on average shorter and apically more rounded than in A. fatidica ; the juxta is also somewhat larger and broader, more pentagonal than in A. fatidica and A. proverai . The basal dilated section of the vesica is large with a well-developed, rounded conical dorsal diverticulum; the ventral carinal bar and the subbasal serrate-dentate plate of vesica are connected by an angled membranous part. The carinal bar and the dentated plate are usually directly connected in the other three close relatives and the dentated plate is regularly stronger and more densely spiny in A. mayrorum than in the related species.

The female genitalia of the three closely related species are very similar (the female of A. proverai is still unknown), although some differences can be found in the length and proportion of the ovipositor, the apophyses anteriores and the appendix bursae. Agrotis mayrorum has, in comparison with A. fatidica , proportionally a longer and more elongated ovipositor, longer apophyses anteriores and a longer appendix bursae; while the ovipositor, the ductus bursae, and the appendix bursae are proportionally longer than in A. mazeli .

Description.

Wingspan: males 40-45 mm, female 31 mm. The external appearance of A. mayrorum is similar to that of A. fatidica , but has narrower, more elongated and somewhat paler coloured forewings and much paler, ochreous-shaded whitish hindwings. Forewing ground colour pale creamy beige, mottled with pale brown and grey; costal area and all veins somewhat darker grey or grey-brown and defined broadly with paler ochreous-grey stripes. Antemedial line indistinct, double, strongest at dark claviform stigma, its lower tooth relatively long. Median fascia absent; median area with a few intracellular dark streaks running from postmedial line to lower cellvein; postmedial line obsolete, appearing as a thin pale shadow defined by a few darker dots between veins. Subterminal line faint, zigzagged, pale ochreous-grey, defined by conspicuous though not very sharply marked chevron-spots; terminal line fine, black(ish), either continuous or divided into a row of fine black lunules and/or streaks; fringe pale creamy beige, occasionally with somewhat darker brown midline. Stigmata well-defined, regularly outlined by black or dark blackish-brown; claviform stigma long, apically faintly rounded, with fine blackish-brown streak connecting it to postmedial line, its filling darker brown; orbicular of variable size and shape, most often flattened-elliptical, sometimes with pointed lateral edges and darker brown centre; reniform stigma large, elliptical, darkened, particularly in its distal half. Intracellular patch between stigmata dark brown or blackish; supracellular marking between crossvein and postmedial line also well-defined, blackish. Hindwing pale whitish or milky-white with fine ochreous sheen, costal area, termen and diffuse marginal stripe suffused with ochreous-brown; veins also brownish. Discal spot weak, small, often obsolete or missing; terminal line more or less continuous, pale ochreous-brown; cilia whitish or ivory-coloured. Forewing underside ochreous-whitish, variably suffused with pale fuscous, with faint discal dot and postmedial line; hindwing underside whitish with fine ochreous sheen, veins darkened, transversal line absent or very pale, shadow-like; discal spot also indistinct, pale brown with whitish centre.

Molecular data.

BIN URI: BOLD: ACE4355. The intraspecific average and maximum distances of the barcode region are 0% (p-dist) (n=5), however intraspecific divergence may increase with additional samples from the Alps. The minimum distance to the nearest neighbour Agrotis mazeli is 1.12%, whereas the minimum distance to Agrotis fatidica is 1.71%.

Bionomics.

Host-plant and early stages are unknown. The adults fly relatively late in the season within a period lasting from late July to mid-August, probably even later. Most of the specimens were obtained by light trapping using both UV tubes and mercury vapour lamp. Adult records are restricted to alpine meadows and scree at high altitudes from ca. 1900 to 2450 m a.s.l. (Figs 57-59 ).

Distribution.

The new species is known from the south-western Alps in Italy (Alpi Cozie) and in France from the Alpes Maritimes and the Alpes-de-Haute-Provence (formerly Basses Alpes, Hautes Alpes).

Figures

Figures 17 - 24. 17 - 20 Agrotis proverai, paratype males, Italy, Abbruzzo region; 21 - 24 Agrotis mayrorum, 21 - 22 holotype male, Italy, 23 - 24 paratype male, Italy.

Figures 25 - 32. Agrotis mayrorum. 25 - 28 paratype males, France, 29 - 30 male, " Corsica ", 31 - 32 paratype female, France.

Gen. figs 4 - 6. Agrotis mayrorum sp. n., paratype, male genitalia.

Gen. figs 7 - 9. 7 Agrotis mayrorum sp. n., male genitalia, " Corsica ", 8 - 9 Agrotis mazeli sp. n., male genitalia, 8 holotype, 9 paratype.

Gen. figs 16 - 18. 16 Agrotis fatidica, female genitalia, Austria, 17 Agrotis mayrorum sp. n., paratype, female genitalia, France, 18 Agrotis mazeli sp. n., paratype, female genitalia, France.

Figures 57 - 59. The type-locality of Agrotis mayrorum.