Thubana siantarensis Park & Heppner, 2023

Park, Kyu-Tek & Heppner, John B., 2023, Review of the genera Thubana Walker and Torodora Meyrick (Lepidoptera: Lecithoceridae) from Sumatra, Indonesia, Zootaxa 5256 (5), pp. 434-456 : 444

Thubana siantarensis Park & Heppner , sp. nov.

LSID: urn:lsid:zoobank.org:act:B80013E1-5148-4111-BE48-03BD973BA844

( Fig. 7 )

Type specimen. Holotype: Female, Indonesia, N. Sumatra, 43 km SW P[ematang] Siantar (HW 4 [forest road 4]), 24–26 Aug. 1992, ca. 1,200 m, J.B. Heppner & E.W. Diehl, gen. slide no. JBH-4151.

Diagnosis. The new species can be distinguished from its congeners by the color pattern of the forewing with dark grayish-brown ground color, the head covered with shiny yellowish-white appressed scales, and the abdomen dark-fuscous dorsally but yellowish white mixed with brownish scales in the last 3-4 segments. The female genitalia also can be distinguished from any other known species by the thumb-shaped sclerotized antrum.

Description. Female ( Figs 7A, B ). Wingspan 15.7 mm.

Head: frons and vertex yellowish white, with same color of erect rough scales laterally. Antenna longer than forewing, about 1.3 times; scape elongated, grayish brown ventrally; flagellum shiny, yellowish white in basal 4/5, then dark brown in apical 1/5, with dark-brown annulations in about basal half. Second segment of labial palpus light brownish white.

Thorax: tegula and thorax deep grayish brown dorsally, with yellowish-white scales laterally. Hind tibia yellowish-white sales dorsally, with deep grayish brown scales apically; tarsi yellowish white with dark-brown scales apically. Forewing densely covered with deep grayish-brown scales irregularly; costal patch large, more or less ovate, yellowish white, near at middle; costa arched from beyond 2/3; apex obtuse; termen oblique; fringe with narrow yellowish-white basal line, yellowish mixing with brownish scales. Hindwing ground color as same as that of forewing; termen with blackish line along margin; fringe with narrow yellowish-white basal line. Abdomen: dark fuscous dorsally on segments I-V and then yellowish white mixing with brownish scales on dorsal surface of segments VI-VIII; spinous zones well-developed.

Female genitalia ( Figs 7C–E ): Abdominal sternite VIII deeply emarginated into U-shape at middle. Antrum thumb-like, heavily sclerotized. Ductus bursae broad, without conjunction between antrum and ductus bursae. Corpus bursae ovate, al song as ductus bursae; signum dish- shaped, positioned in distal 1/3, with minute conical spines, stronger spines along posterior margin.

Male unknown.

Distribution. Indonesia (N. Sumatra).

Etymology. The specific name is derived from the name of the nearest town where the type specimen was collected, Pematang Siantar.

Remarks. Another species with a similar wing pattern was collected from the same locality and date, but it was found that both are different species from each other by the female genitalia. That species, however, is not included in this study, due to the damage of the genitalia during collection.

Figures

FIGURE 7. Thubana siantarensis Park & Heppner, sp. nov.: A, adult, female, holotype; B, head, dorsal view; C, female genitalia, slide no. JBH-4151; D, close-up pregenital segments with antrum; E, close-up signum. Scale bar: 1.0 mm.