Elachista brevis, Sruoga, Virginijus & Prins, Jurate De, 2009

Sruoga, Virginijus & Prins, Jurate De, 2009, The Elachistinae (Lepidoptera: Elachistidae) of Kenya with descriptions of eight new species, Zootaxa 2172, pp. 1-31 : 4-7

Elachista brevis , new species

( Figs. 3 , 5 , 11–14 , 15 )

Type material. Holotype: 3, KENYA, Naivasha region, 1960 m, Hell’s Gate National Park, 00°53’S 36°19’E, 17.iv.2002, leg. J. De Prins, specimen ID RMCA ENT 0 0 0 0 0 5186, gen. prep. MRAC / KMMA 0 0 483 ( RMCA).

Diagnosis. E. brevis is a medium-sized and lightly-coloured species belonging to E. freyerella species group. In wing pattern and male genitalia, this species is rather close to E. ksarella Chrétien, 1908 known from Algeria (for the genitalia image please refer to Parenti 1972). The main differences in male genitalia between E. brevis and E. ksarella are (1) the basal fold of the costa in E. brevis extends to about 1/2 length of valva, in E. ksarella to about 3/5 length of valva; (2) the sacculus in E. brevis is nearly straight, in E. ksarella it is concave in the middle; (3) the cucullus in E. brevis is wide, meeting the costa at about right angle, and in E. ksarella it is rounded and its apical part is obviously narrower; (4) the phallus length/width in E. brevis = 11.8, and in E. ksarella = 7.7; (5) the phallus length/cornutus length in E. brevis = 3.7, and in E. ksarella = 7.7.

Male ( Fig. 5 ). Forewing length 3.3 mm; wingspan 7.3 mm (n=1). Head of holotype is worn, with only a few scales left, labial palpus whitish. Forewing: ground colour whitish, mottled with ochreous or greyish at tips of scales, especially along costa; brownish black-tipped scales forming two small spots, one at 2/5 and another at 2/3 of wing; fringe greyish. Hindwing grey, fringe slightly paler.

Female. Unknown.

Male genitalia ( Figs. 11–14 ). Uncus lobes curved, basally bulbous, narrowed towards tip; ventral surface covered with mixture of short and thick and long setae. Spinose knob of gnathos round, nearly as long as wide. Valva about 3.5 times longer than wide; sacculus nearly straight, distally with very short spine; cucullus meeting costa at about right angle, one long seta on outer surface; basal fold of costa extending to about 1/2 of valva, where it meets distal fold forming small hump. Median margin of juxta lobes strongly sclerotized, weakly S-shaped; lobes triangular, folded towards apex; ventral surface with several setae ( Fig. 13 ). Digitate process relatively short, about three times shorter than valva, distally dilated and covered with few thin setae.

Vinculum produced into short and wide saccus. Phallus straight, relatively wide (only 13 times longer than wide) and short (about 0.8 as long as valva); vesica with one long cornutus and group of tiny spines ( Figs. 12, 14 ).

Biology. Unknown.

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

Distribution. So far known only from Hell’s Gate National Park in the Rift Valley Province of Kenya ( Figs. 3 , 15 ).

Etymology. The species name is derived from the Latin brevis (short) in reference to the short distal spine of the sacculus.

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

Figures

FIGURE 15. Collecting localities of Elachistinae species in Kenya: 1, Arabuko Sokoke Forest National Park; 2, Aberdares National Park; 3, Hell's Gate National Park; 4, Kakamega Forest National Reserve.

FIGURES 1 – 4. Collecting localities in Kenya. 1, Arabuko Sokoke Forest National Park; 2, Aberdares National Park; 3, Hell’s Gate National Park; 4, Kakamega Forest National Reserve.

FIGURES 5 – 10. Adults of Elachista species. 5, E. brevis sp. n., male, holotype. Specimen ID: RMCA ENT 000005186; 6, E. chelonitis Meyrick, female. Specimen ID: RMCA ENT 000002718; 7, E. kakamegensis sp. n., male, holotype. Specimen ID: RMCA ENT 000005183; 8, E. kakamegensis sp. n., female, paratype. Specimen ID: RMCA ENT 000005185; 9, E. longispina sp. n., male, holotype. Specimen ID: RMCA ENT 000005182; 10, E. planca sp. n., female, holotype. Specimen ID: RMCA ENT 0 0 0 0 0 5181. Scale bar 1 mm.

FIGURES 11 – 14. Elachista brevis sp. n., male genitalia, holotype. 11, general view (phallus removed); 12, phallus. Scale bar 0.1 mm; 13, juxta lobes region; 14, apical part of phallus. Gen. prep. MRAC / KMMA 0 0 483, specimen ID: RMCA ENT 0 0 0 0 0 5186.