Elachista acutella Kaila, in Kaila et al.: 2003
Creators: name: Kaila, Lauri
name: Nupponen, Kari
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Lepidoptera
Elachistidae
Elachista
Elachista acutella

description: Elachista acutella Kaila, 2003
Figs. 19, 43
Elachista acutella Kaila, in Kaila et al.: 2003: 80.
Material examined: Type material: holotype ♂: Russia, S. Ural, 51°23’N 56°49’E, 130–340 m, Orenburg distr., 6 km W Donskoje village, Mt. Verbljushka, 10.vi.1998, T. & K. Nupponen leg. (L. Kaila prep. 3390; Coll. Nupponen). Paratypes (3 ♂): the same locality, 10.–12.VI.1998, 1 ♂, J. Junnilainen leg. (Coll. Junnilainen), 2 ♂, T. & K. Nupponen leg. (Coll. Nupponen, MZH). Other material: Kazakhstan: 48°38’N 57°54’E, 200 m, Kumzhargan sands by Emba River, 5.vi.2011, 2 ♂, K. Nupponen leg. (DNA sample 22509 Lepid. Phyl.; Coll. Nupponen, MZH).
Diagnosis. E. acutella is a unicolorous white species. It is distinguishable from other species of the E. subula species complex, apart from E. cultella, by the long uncus lobes which are 2x as long as wide, as well as the medially produced juxta lobes whose median and distal margins are joined at an acute angle. The genitalia of E. acutella could be characterized as being prolonged in every direction as compared to E. cultella; thus ratios of relative sizes between different parts do not markedly differ but the general appearance, best visible in images, does. The phallus of E. acutella is narrow, its length approximately 20x its width at its median area, whereas in E. cultella the length of phallus is approximately 9x its width at its median area. The acute shape of the juxta lobes in E. acutella, as compared to other species, also readily distinguishes E. acutella from E. cultella.
Molecular characterization. There was no intraspecific variation among the three included specimens. Of the species included the closest taxon in terms of similarity of barcodes is E. scalpra (distance 3.61 %).
Redescription. Forewing length 5 mm. Labial palpus straight or upcurved, white, length equal to diameter of head. Head, neck tuft, thorax, scape and pedicel of antenna white; scape with distinctive pecten formed of elongate, white scales; flagellum brown. Fore- and midleg inwardly dark grey, outwardly white, tarsal articles distally pale; hindleg pale grey, spurs nearly black, tibia and tarsus above grey with distally pale tibia and tarsal articles. Forewing chalky white, basal third of costa narrowly dark grey. Indistinctly developed plical and discal spots, if present, formed of a few dark grey scales; fringe concolorous with forewing ground colour. Underside of forewing dark grey, in basal third two broad, pale longitudinal lines, fringe white. Underside of hindwing grey, translucent, except on costal side where it is dark grey; fringe pale grey.
Male genitalia. Uncus lobe elongate, twice as long as broad, sparsely covered by setae distally, lobes separated by distinct U-shaped incision, depth of incision half of the length of uncus. Spinose knob of gnathos basally narrow, oval-shaped. Valva elongate and straight, 6–6.5x as long as wide in the widest point a little basal to middle; Cucullus indistinctly delineated, elongate, distally somewhat tapered, apically rounded. Digitate process narrow, parallel-sided, 0.25x as long as valva, distal 2/3 with setae. Juxta lobe somewhat shorter than digitate process, distally produced and with a few setae at apex; median margin straight, joining the straight distal margin at an acute angle. Median plate of juxta narrowed posteriorly, forming dorsally projected lobe. Vinculum broad, U-shaped. Phallus 0.7–0.8x as long as valva, slightly bent, about 10x as long as broad at its broadest place near base, tapered into sclerotized, acute-tipped apex. Vesica with cornutus that consists of oval, indistinctly delineated, weakly sclerotized elongate plate which one blunt tooth.
Female. Unknown.
Biology. The species inhabits xerothermic slopes in calcareous and sandy steppes.
Distribution. W. Kazakhstan, Russia (S. Ural).
Etymology. The name acutella was originally derived from two traits: the distally acute-shaped juxta lobes, as well as the acute-tipped apex of the phallus.
description: Published as part of Kaila, Lauri & Nupponen, Kari, 2018, A review of the Elachista subula Parenti species complex (Lepidoptera, Elachistidae), with descriptions of nine new Palearctic species, pp. 401-433 in Zootaxa 4433 (3) on pages 418-420, DOI: 10.11646/zootaxa.4433.3.1, http://zenodo.org/record/1290285