Roeslerstammia metaplastica Meyrick

Hirowatari, Toshiya, Huang, Guo-Hua & Wang, Min, 2017, Review of the genus Roeslerstammia, with a new species from China (Lepidoptera, Roeslerstammiidae), ZooKeys 668, pp. 107-122 : 108-109

Roeslerstammia metaplastica Meyrick Figs 1, 2, 3

Roeslerstammia metaplastica Meyrick, 1921: 439, lectotype here designated; Kyrki 1983: 322; Heppner 2005: 27.

Roeslerstammia hemiadelpha Meyrick, 1922: 553, lectotype here designated; Kyrki 1983: 322. syn. n.

Roeslerstammia hemidelpha (!): Heppner 2005: 26. Misspelling.

Type material.

Lectotype ♂ (here designated), "Murree [Hills, Punjab] / 7500 ft/June 18 / Dutt Coll", "Presented by / R.L.E.Ford. / B.M.1949 –487.”, " Roeslerstammia metaplastica Meyrick / det.T.B.Flecher", “♂” (Fig. 1A, B), in BMNH. B.M. Genitalia slide No. 29548.

Paralectotype ♀, same labels as lectotype except for “♀” (Fig. 1C, D), in BMNH. B.M. Genitalia slide No. 29549.

Lectotype ♂of Roeslerstammia hemiadelpha Meyrick, 1922 (here designated), "Murree Hills / Punjab / 7500 ft / May 1920 / Dutt Coll", "Presented by / R.L.E.Ford. / B.M.1949 –487.”, " Roeslerstammia hemiadelpha Meyrick / det.T.B.Flecher", "in Cop /C" “♂” (Fig. 1E, F), in BMNH. B.M. Genitalia slide No. 29550.

Paralectotype ♀of Roeslerstammia hemiadelpha Meyrick, 1922, same labels as lectotype except for “♀” (Fig. 1G, H), in BMNH. B.M. Genitalia slide No. 29551.

Diagnosis.

Distinguished from the other species by the narrow triangular creamy-white tornal spot of the forewing. In the male genitalia, the uncus is rectangular, apically bilobed and broad; the valva has a short sacculus terminating in a blunt process; the phallus is short, sinuate, and tapered toward the apex. In the female genitalia, the ductus bursae is slender, nearly straight; the corpus bursae is long-ellipsoidal, with a strongly sclerotized sword-shaped signum.

Description.

Male (Fig. 1A, E).

Forewing length 5.3 mm. Wing expanse 11.3 mm.

Head vertex, including between antennae, with raised pale yellow hairs; frons smooth, ochreous with golden luster, laterally pale yellow along eyes. Eyes moderate, interocular index ca 0.8. Antenna filiform, ca 0.9 × as long as forewing; scales in flagellar segments near the middle of the antenna somewhat raised; scape pale yellow on basal half and dark brown on distal half; flagellum dark brown on basal 2/3, white on distal third, densely ciliate with sensory hairs ventrally. Labial palpus slightly upcurved, relatively long ca 2.2 × as long as horizontal eye diameter, 3rd segment as long as 2nd, entirely smooth, 2nd pale yellow, 3rd pale yellow with dark brown laterally.

Thorax tegula pale yellow (scales partly removed); mesonotum dark brown with metallic luster. Fore- and midlegs pale yellow, tarsomeres brown distally; hindleg pale yellow. Forewing, lanceolate, dark brown with metallic blue or golden luster; a narrow indistinct oblique marking present at basal 2/3 near costa, a line along fold from base, terminating in a narrow triangular creamy-white tornal spot; fringe dark brown. Hindwing dark brown, darker near apex; fringe dark brown.

Abdomen pale brown with golden luster, terminally with pale yellow tufts.

Male genitalia (Fig. 2). Uncus rectangular, apically broad and bilobed. Tegumen broad, slightly shorter than uncus. Gnathos consisting of two slender arms united medially with a membranous part. Valva rectangular; sacculus short, about 1/3 length of valva, terminating in a blunt process; a small pad of long hair scales near the base ventrally. Vinculum broad ventromedially; saccus cylindrical, as long as dorsal part of tegumen. Phallus, short, sinuate, tapered toward apex, with indistinct minute spine-like cornuti.

Female (Fig. 1C, G).

Forewing length 5.5 mm. Wing expanse 12.1 mm.

Similar to male but differs as follows: scales in flagellar segments near the middle of the antenna not raised; flagellum without dense sensory hairs ventrally. Forewing with the oblique marking on costa broader, but indistinct in " R. hemiadelpha ".

Female genitalia (Fig. 3). Papillae anales broad and truncate in ventral view, nearly rectangular in lateral view. Apophysis posterioris slender, 0.7 × as long as papilla analis. Apophysis anterioris slender and moderate in length, 0.6 × as long as eighth tergite. Eighth tergite weakly sclerotized, dorsal posterior margin nearly straight. Ostium bursae situated at posterior margin of eighth abdominal segment, posterior margin weakly emarginate at middle. Ductus bursae slender, nearly straight. Ductus seminalis attached to ductus bursae near ostium. Corpus bursae long-ellipsoidal, with a strongly sclerotized sword-shaped signum.

Host plant.

Unknown.

Distribution.

India (Punjab).

Remarks.

Meyrick (1921) described R. metaplastica from the "Murree Hills, Punjab" based on five specimens collected by Dutt in June. Subsequently, Meyrick (1922) described R. hemiadelpha based on six specimens, which were collected by the same collector in the same locality in May 1920. Meyrick distinguished his two species on the basis of external characters such as coloration and wing markings (see Fig. 1). Since then, these specimens have not been studied again and they have been regarded as two distinct species following Meyrick. Both the male and female genitalia of some syntypes of R. metaplastica and R. hemiadelpha were examined, but there were no differences in the shape of male or female genitalia between the two taxa. Therefore, it was concluded that the latter is a junior synonym of the former. Of the original syntype series, only one male and female of each taxon was found in BMNH: both males are selected as lectotypes.