Thisizima subceratella, Yang, Linlin, Li, Houhun & Kendrick, Roger C., 2012

Yang, Linlin, Li, Houhun & Kendrick, Roger C., 2012, Taxonomic study of the genus Thisizima Walker, 1864 in China, with descriptions of two new species (Lepidoptera, Tineidae), ZooKeys 254, pp. 109-120 : 114-115

Thisizima subceratella sp. n. Figs 3−9

Type material.

CHINA, Holotype ♂, Fujian Province: Mt. Tianzhu (24°35'N, 117°55'E), Xiamen City, 220 m, 12.ix.2010, leg. Yinghui Sun & Jing Zhang (NKU).

Paratypes: 2 ♂, 30.viii,19.ix.2010, other same data as holotype, genitalia slide No. NKYLL010 (NKU). Hainan Province: 1 ♂, Mt. Wuzhi (18°31'E, 109°24'E), 700 m, 19.v.2007, leg. Zhiwei Zhang & Weichun Li (NKU). Hong Kong: 2 ♂, Kadoorie Agricultural Research Centre (22°25'N, 114°06'E), Shek Kong, N.T., UTM: 50Q KV 030833, 125 W MBF, 28.iv.1997, leg. R.C. Kendrick (KFBG).

Description.

Imago (Figs 3−8). Wingspan 18.5−20.5 mm in male. Vertex and frons yellowish white, tinged with brown around eyes. Antenna about 1.2 × length of forewing including fringe; scape yellowish white above, scattered with brown scales below, pecten with 8−12 black bristles; flagellum ochreous yellow, compressed broadly and flatly. Labial palpus yellowish white, first segment black on outer surface, second segment black on outer surface of basal 2/3, with sparse black lateral bristles. Thorax black, tegula black on anterior half and dark cupreous brown on posterior half. Forewing index about 0.3; ground color creamy white, with scattered dark brown scales on distal 1/4; a triangular black patch on basal 1/5, broader at costa, sinuate along outer margin; a broad black costal blotch narrowly confluent with basal patch on anterior margin, curved in W shape on posterior margin, its basal half apically rounded and reaching half width, distal half triangularly crossing midwing; two small indistinct spots along costa before apex; termen and dorsum scattered with faint dark brown dots; fringe light yellowish brown. Hind wing index 0.38; cupreous brown; fringe grayish brown; frenulum one stout bristle. Fore leg black except distal half of coxa yellowish brown on ventral surface; mid leg black except tarsus yellowish brown on ventral surface, spurs dark brown; hind leg yellowish brown mixed with black scales.

Male genitalia (Fig. 9). Vinculum convex anteriorly in arch, slightly convex at middle on posterior margin; with a longitudinal suture in middle posteriorly, 0.5 × length of vinculum. Uncus membranous, trapezoidal; uncus lobes digitate, slightly sclerotized, with elongate setae on ventral surface. Valva with base broad and gently arched, connected ventrally at base by a sclerotized, somewhat funnel-shaped plate on inner surface; basal 2/3 membranous and inverted fan-shaped, scattered with strong hairs on outer surface; apex as wide as base, heavily sclerotized, sinuate, dorsoapically with a tuft of 3−4 strong spines, ventroapically convex, with dense, stout spines on outer surface. Juxta membranous. Aedeagus membranous dorsally, sclerotized ventrally, with a shallow keel at base; cornutus absent.

Female. Unknown.

Diagnosis.

The new species is quite similar to Thisizima ceratella , but can be separated by the forewing having a broad blackish costal blotch narrowly confluent with the basal patch on anterior margin, curved in W-shape on posterior margin; while Thisizima ceratella has an irregular cupreous black costal stripe broadly confluent with the basal patch on anterior margin, curved outward before middle on posterior margin.

Distribution.

China (Fujian, Hainan, Hong Kong).

Etymology.

The specific name is derived from the Latin prefix sub-, meaning similar, and another specific name ceratella, referring to the similarities of the two species.

Remarks.

K. Tuck (BMNH) assisted us to check the identity of Thisizima ceratella . Unfortunately, the holotype has lost its hindwings and abdomen. The late G. Robinson had therefore dissected a male specimen identified as ceratella in the Meyrick collection, collected in Koni, Burma. Tuck kindly compared our illustrations of Thisizima subceratella sp. n.with Robinson’s slide BMNH Microlep. No. 27736. He noticed a small but distinct difference in the shape of the valva: in Robinson’s dissection the valva is slightly larger and therefore extends further laterally and has five strong spines, whereas our illustration shows a relatively short valva with only 3−4 spines on each.

Furthermore, the adult photograph of Thisizima ceratella given by Robinson et al. (1994) shows that the forewing pattern is coincident with Walker’s original description. We thus base our understanding of the identity of Thisizima ceratella on this dissected specimen.

There are many tineid species showing small differences in genitalia, but they can usually be recognized by the external morphology, such as forewing pattern and venation (eg. species of Monopis Hübner). The forewing pattern in the new species is quite different from that of Thisizima ceratella , and the shape of the valva does have small but distinct difference between the two species, which we regard as sufficient evidence that this is a good species.