Elachista loeiensis Sruoga & Kaila, 2019

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 : 25-26

Elachista loeiensis Sruoga & Kaila sp. nov.

urn:lsid:zoobank.org:act:C7B51906-9FE4-4AA2-9220-C91DB0BF31F7

Figs 63–66

Diagnosis

The wing pattern of this species is hardly distinguishable from many others of the Elachista freyerella species group. It is one of the six known eastern Palaearctic or Oriental species of the E. freyerella species group whose phallus contains a cornutus. These species can be divided into two groups: species with the cornutus elongate, and species with the cornutus short and arrow-shaped. Elachista spiculifera Meyrick, 1922 described from India, E. cornutifera Sruoga, 1995 described from Russian Far East, E. nipponicella Sugisima, 2006 described from Japan and E. loeiensis Sruoga & Kaila sp. nov. belongs to the species group with an elongate cornutus. They can be separated from each other as follows: the distal spine of the cucullus is very robust in E. spiculifera (cf. Sruoga & Diškus 2006), slender in the three other species. The phallus is distally markedly bent in E. cornutifera (cf. Sruoga 1995) and E. nipponicella (cf. Sugisima 2006), evenly bent from middle to apex in E. loeiensis Sruoga & Kaila sp. nov. Elachista stichospora Meyrick, 1932 and E. siamensis Sruoga & Kaila sp. nov. have a short, arrow-shaped cornutus. They can be separated from each other as follows: the distal spine of E. stichospora is evenly bent towards cucullus, straight in E. siamensis Sruoga & Kaila sp. nov.; the phallus is very narrow and distinctly longer than valva, with a small tooth near apex in E. stichospora ( Sruoga & Diškus 2006) ; the phallus is broader, and approximately as long as the valva in E. siamensis Sruoga & Kaila sp. nov.

Etymology

In reference to the host location, Loei Province, northeastern Thailand, where the holotype was collected.

Type material

Holotype

THAILAND • ♂; Loei Province, Phu Luang Wildlife Sanctuary ; 700–900 m; 8–14 Oct. 1984; Karsholt, Lomholdt and Nielsen leg.; ZMUC 2073 .

Description

Male

EXTERNAL CHARACTERS ( Figs 63–64 ). Forewing length 2.6 mm; wingspan 5.8 mm (n = 1). Head: frons shiny, creamy white; labial palpus upwards curved, diverging, about two times as long as width of head; antenna greyish brown, basal articles weakly annulated with paler rings; pecten present as a few short stiff seta-like scales at base of scape. Forewing ground colour pale greyish white, powdered with greyish brown-tipped scales; distal half of wing darker than basal; fringe scales greyish brown. Hindwing and its fringe scales greyish brown.

MALE GENITALIA ( Figs 65–66 ). Uncus lobes narrow and long, 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 about 1.7 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 right-angled; basal fold of costa extended to ⅔ of valva, where it meets distal fold forming broad indistinct hump. Median plate of juxta about 2.3 times as long as broad, proximal end formed as rounded sac; medial margin of juxta lobes strongly sclerotized; lobes elongate, broadest medially, tapered distally; ventral surface with few long and short setae. Digitate process ⅓ length of valva, narrow, distally somewhat dilated and setose. Vinculum produced into very long parallel-sided blunt-tipped saccus. Phallus about 0.9 length of valva, narrow, broadest basally, curved at basal ¼ and more strongly at distal ⅓; caecum dorsally with cusp-like lobe whose anterior margin is concave; vesica with one stout straight cornutus, about 1/6 length of phallus.

Female

Unknown.

Biology

Unknown.

Flight period

The only known specimen was captured in October.

Distribution

So far this species is known only from northeastern Thailand.

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.

Figures

Figs 63–66. Elachista loeiensis Sruoga & Kaila sp. nov., holotype, ♂ (ZMUC 2073). 63. Adult male. 64. Head, latero-frontal view. 65. General view of male genitalia (phallus removed). 66. Phallus. Scale bars: 63–64 = 1 mm; 65–66 = 0.1 mm.