Elachista, Treitschke, 1833

Sruoga, Virginijus, Kaila, Lauri & Rocienė, Agnė, 2019, The Elachistinae (Lepidoptera: Gelechioidea, Elachistidae) of Thailand, with description of eight new species, European Journal of Taxonomy 574, pp. 1-34 : 23-25

Elachista species Nr. VS3/ 29.03.19

Figs 59–62

Diagnosis

Elachista species Nr. VS3/ 29.03.19 is a small species with peculiarly coloured forewings and a dorsoventrally flattened head. In wing pattern this species is comparable to E. heteroplaca (for illustrations, we refer to Kaila 1998: figs 1–5), E. lorigera Meyrick, 1921 (for illustrations, we refer to Kaila 1998: figs 6–7), E. albrechti (for illustrations, we refer to Kaila 1998: figs 12–17) and Thailandese species of Elachista saccharella species group described here as new (comprising E. oryx Sruoga & Kaila sp. nov., E. pellineni Sruoga & Kaila sp. nov., E. capricornis Sruoga & Kaila sp. nov. and E. phichaiensis Sruoga & Kaila sp. nov.). Female genitalia of E. species Nr. VS3/ 29.03.19 are distinctive with the long, narrow, almost straight signum and corpus bursae devoid of internal spines.

Material examined

THAILAND • 1 ♀; Lampang, Phichai ; 18°20ʹ N, 99°32ʹ E; 1–30 Oct. 2007; M.J. Pellinen leg.; MZH VS3 / 29.03.19 .

Description

Female

EXTERNAL CHARACTERS ( Figs 59–60 ). Forewing length 3.4 mm; wingspan 7.3 mm (n = 1). Head: frons shiny, creamy white; vertex and neck tuft brownish white, some scales with dark brown tips; labial palpus upwards curved, diverging, about 1.8 times as long as width of head, creamy white, third segment medially with few dark brown scales; scape creamy white below, with few dark brown scales above, without pecten; flagellum creamy white below, greyish brown above, annulated with paler rings, last flagellomere creamy white. Thorax grey brown. Forewing: ground colour greyish brown with scattered rusty brown scales, costa narrowly dark except at ⅓ where indistinctly delimited oblique creamy white streak and at ⅔ where larger oblique creamy white streak almost reaches fold; in the middle of wing at fold blackish brown spot formed of raised scales; tornal area creamy white; narrow longitudinal blackish brown stripe to apex of wing; fringe scales brownish grey, fringe line dark brown. Hindwing and its fringe scales brownish grey.

FEMALE GENITALIA ( Figs 61–62 ). Papilla analis longer than wide, setose. Apophysis posterioris slightly longer than apophysis anterioris. Ostium bursae situated at posterior margin of sternum 7, occupying 2/5 of the space between apophyses anteriores, dorsal wall covered with minute spines. Antrum large, about 1.5 times longer than wide, inwardly densely covered with small spines. Colliculum weakly sclerotized, as long as antrum. Ductus bursae membranous, gradually widened towards corpus bursae with which it is incepted without distinct border; corpus bursae without internal spines. Signum long, narrow, almost straight, with a few rows of teeth.

Male

Unknown.

Biology

Unknown. The specimen was collected by artificial light.

Flight period

The only known specimen was captured in December.

Distribution

So far this species is known only from northern Thailand.

Remarks

This female singleton externally resembles several other species found at the same site. It may be conspecific with some other species of Elachista albrechti-heteroplaca species group, now only known from males. Therefore, this taxon is documented but not named pending availability of additional male material.

Figures

Figs 59–62. Elachista sp. (MZH VS3/29.03.19). 59. Adult female. 60. Head, latero-frontal view. 61. Female genitalia, caudal part. 62. Ductus and corpus bursae. Scale bars: 59–60 = 1 mm; 61– 62 = 0.1 mm.