Elachista adunca Sruoga, 2010, new species

Elachista adunca, new species

(Figs. 1, 2, 5, 6, 10–16)

Type material. Holotype: ɗ, ‘ Ecuador | Pichincha Province | 11 km NW Aloag | 24.ii.2007, V. Sruoga leg [it].; ɗ | VS310 | Genitalia slide’. In VPU.

Diagnosis. In wing pattern and genitalia, this species is rather close to E. albisquamella Zeller, 1877, known from Colombia (for illustrations, see Kaila 2000) and E. laxa, known from the same locality as E. adunca. The main differences between E. adunca, E. albisquamella and E. laxa are the following:

The flagellum of antenna in E. adunca lacks visible cilia; in E. albisquamella and E. laxa it is densely ciliated below (length of cilia is about 1/3 of diameter of shaft in E. albisquamella and 2/3 of diameter of shaft in E. laxa);

The juxta lobe in E. adunca is 1.5 times longer than wide; in E. albisquamella it is 3 times longer than wide;

The phallus in E. adunca is gradually bent, s-shaped and longer than valva; in E. albisquamella it is straight and shorter than valva; in E. laxa it is curved at basal 1/2 and 4/5;

The apex of phallus in E. adunca is blunt; in E. laxa it is tapered;

The median ridge of vinculum in E. adunca is narrow; in E. albisquamella and E. laxa it is broad; The saccus in E. adunca is short and narrow; in E. laxa it is short and wide.

Male (Figs. 5, 6). Forewing length 4 mm; wingspan 8.7 mm (n=1). Head: Frons shiny pale grey; vertex and neck tuft fuscous grey; labial palpus 1.4 times as long as width of head, whitish above except base and tip of third segment brownish grey, below brownish grey except basal part of second segment; antenna brownish grey, basal articles weakly annulated with paler rings. Thorax and tegulae fuscous grey. Forewing ground colour brownish grey, mottled by darker tips of scales; distal half of wing darker than basal; fringe scales grey. Hindwing dark brownish grey, its fringe scales somewhat paler.

Female. Unknown.

Male genitalia (Figs. 10–16). Uncus lobes small, widely separate, apically rounded, ventral surface densely covered with long scales. Tegumen short and broad. Basal arms of gnathos fused along distal half; spinose knob of gnathos about 1.5 times longer than wide, dorsocaudally directed, only apex curved ventrad. Valva strongly curved and broadened towards cucullus; basal fold of costa gradually bent, distal fold small and wide, weakly sclerotized. Sacculus strongly curved joining wide cucullus without angle. Juxta lobes 1.5 times longer than wide, with some setae in ventral surface. Digitate process very narrow, about 5.5 times longer than wide, with single seta near apex. Vinculum with narrow median ridge, tapered towards small saccus. Phallus longer than valva, gradually bent, s-shaped, without caecum, ductus ejaculatorius posteriorly directed; carina formed from small spines around distal opening.

Biology. Unknown.

Flight period. Based upon the single specimen available, adults fly in February.

Distribution. So far this species is known only from Pichincha Province of Ecuador (Figs. 1, 2).

Etymology. The species name is derived from the Latin aduncus (bent, curved) in reference to the curved phallus.

Remarks. The holotype is in poor condition; the forewing and head are somewhat rubbed, the antennae are partly broken and therefore the description of external characters is incomplete.