Elachista arcuata, Sruoga & Rocienė, 2018

Sruoga, Virginijus & Rocienė, Agnė, 2018, Three new species of Elachistidae (Lepidoptera: Gelechioidea) from India, Zootaxa 4394 (4), pp. 575-585: 576-577

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Elachista arcuata

sp. nov.

Elachista arcuata   , sp. nov.

( Figs. 1–6 View FIGURE 1 View FIGURES 2–5 View FIGURE 6 )

Type material. Holotype: ♂, India, Uttarakhand, Dehradun district, Rishikesh , 30°08’13.73”N 78°19’55.12”E, 450 m, 09.viii.2010, V. Sruoga leg. Gen. prep. VS468 (LEU). GoogleMaps  

Diagnosis. The wing pattern of this species is hardly distinguishable from many others of the ElachiSta freyerella   species group. However, in male genitalia, the strongly bent phallus separates this species well from all the other known species of the E. freyerella   species group.

Male ( Figs. 2–3 View FIGURES 2–5 ). Forewing length 2.5 mm; wingspan 5.6 mm (n=1). Head: Frons creamy white; vertex and neck tuft creamy white, mottled with greyish brown; labial palpus almost as long as width of head, creamy white with some shine above, greyish brown below; antenna whitish brown, annulated with greyish brown, annulation indistinct in distal part. Thorax, tegula and forewing creamy white, strongly mottled with greyish brown tipped scales; wing darker beyond middle; antemedian fascia white, indistinct; blackish brown tipped scales beyond the middle of wing forming two irregular spots near the costal and tornal margins; same scales present in basal and apical parts, where they form small elongate spots; white costal and tornal spots indistinct; apical spot indistinctly delimited, small, creamy white, at base of fringe scales at apex; fringe scales whitish grey, fringe line blackish brown. Hindwing grey-brown, its fringe scales somewhat paler.

Female. Unknown.

Male genitalia ( Figs. 4–6 View FIGURES 2–5 View FIGURE 6 ). Uncus lobes narrow, about 3.5 times longer than wide, apically curved and tapered to pointed apex; ventral surface covered with mixture of short and thick, and long and slender setae. Basal arms of gnathos reinforced, spinose knob small, 1.5 times as long as wide. Valva broadest in basal part; sacculus weakly concave medially, distally with stout spine; cucullus neither expanded nor produced towards costa, tip almost rightangled; basal fold of costa extended to 2/3 of valva, where it meets distal fold forming a small hump. Medial margin of juxta lobes strongly sclerotized; lobes elongate, broadest medially, tapered distally; ventral surface with 4–5 long and 8–10 short setae. Digitate process narrow, distally obliquely expanded, covered with short and thin setae. Vinculum produced into long parallel-sided blunt-tipped saccus. Phallus narrow tubular, broadest at caecum, strongly curved at about 1/5 and 4/5; caecum dorsally with cusp-like lobe whose anterior margin is concave.

Biology. Unknown.

Flight period. The only known specimen was captured at the beginning of August.

Distribution. So far this species is known only from northern India ( Fig. 1 View FIGURE 1 ).

Etymology. The species name is derived from the Latin arcuata   (arched, bow-shaped) in reference to the shape of the phallus.

Remarks. The phallus is somewhat distorted during dissection (Gen. prep. VS468) and therefore looks constricted medially in Fig. 5 View FIGURES 2–5 .