Platychasma elegantula Chen, Kishida & Wang

Chen, Liusheng, Kishida, Yasunori & Wang, Min, 2008, A new species of Platychasma (Lepidoptera: Notodontidae) from China, Zootaxa 1842, pp. 63-65 : 63-65

Platychasma elegantula Chen, Kishida & Wang sp. nov. ( Figs. 1, 2 , 5 )

Description: Male. Head dark brown. Antenna filiform, brown; labial palpus yellowish brown, porrect and reaching beyond the frontal tuft, second segment with yellow scales, tip cuspidal; vertex covered with yellow to brown hairs; compound eyes naked and rounded, black. Thorax covered with dark brown long hairs uniformly. Thorax and the second segment of abdomen dorsally brown; abdomen primrose yellow. Tibia of legs fringed with long yellow brown hairs. Forewing length: 23-26 mm. Forewing broad and long; specimens collected in May with costal margin yellow ( Fig. 2 ), in July brown; subterminal fasciae margined with yellow from middle to dorsum; costa straight, smoothly curved at base, less protruded outwardly basally than P. v i rg o and P. flavida ; apex slightly pointed; termen rounded with serrated cilia at the end of each vein; tornus smoothly rounded; dorsum with two dentations, one of near basal area is large, and another near tornus is small. Hyaline cell at base of anal vein very large. Antemedial fasciae narrow, yellowish, inner margin dark brown basally, outer edge from cell to costa intermittent; medial fasciae two-ply, inner line yellowish, outer line brown; subterminal line ivory white, from near apex to tornus. Hindwing broad, ground color yellow, submarginal area covered with brown scales. Underside of the wings light yellow. Male genitalia ( Fig. 5 ): uncus stubby, slightly concaved dorsally; gnathos with two crook-shaped branches, aculeated apically; tegumen high and narrow; valva narrow and long, with a slender ventral process apically; sacculus with a thumb-shaped process; juxta trapezium, posterior margin double reversed triangle; saccus trigonal, apex slightly rounded; aedeagus stout, heavily sclerotized, carina penis with several thorn like processes apically.

Type Material: Holotype: Male, Mao’ershan National Nature Reserve, Guilin City, Guangxi Zhuang Autonomous Region, China, 800m, 21 May 2007, leg. Liusheng Chen. Paratypes: 1 male, Mao’ershan National Nature Reserve, Guilin City, Guangxi Zhuang Autonomous Region, China, 15 May 2004, leg. Min Wang; 1 male, 4 May 2007, leg. Liusheng Chen, the same location as holotype; 1 male, Shunhuangshan National Forest Park, Dong’an County, Yongzhou City, Hunan Province, China. 21 May 2007, leg. Min Wang and Liusheng Chen. All type specimens are deposited in the Insect Collections of Department of Entomology, South China Agricultural University, Guangzhou, P. R. China.

Distribution: China (Guangxi Autonomous Region; Hunan Province).

Etymology: The name is derived from the Latin “elegantulus”, meaning slightly noble.

Remarks: The new species can be easily distinguished from P. v i rg o by the adult facies ( Figs. 1, 2, 3 ), with a forewing costa that is straight and lacking basal swelling, and a median fascia of yellow to brown. The male genitalia of P. elegantula are similar to those of P. v i rg o ( Figs. 5, 6 ), but differ as follows: the apex of the valva is smooth; the gnathos is smaller, short and crook-shaped, and about half the length of the uncus; the aedeagus is stout, with thorn-like processes apically.

Discussion: The new species has characteristics of both Platychasma and Cyphanta . The forewing fasciae are similar to Platychasma , while the smooth and straight forewing costa is similar to Cyphanta ( Fig. 4 ). The valva of the male genitalia are similar to those of Platychasma , but the aedeagus is stout, and has a toothed portion caudally, which is a character present in Cyphanta ( Fig. 7 ). It is possible P. elegantula represents an intermediate species between Platychasma and Cyphanta . Sugi (1994) described the genus Paracyphanta on the basis of Thai and Sumatran species, of which the male genitalia are quite different. Herein, P. elegantula is placed for the present in Platychasma , awaiting a systematic review of both Platychasma and Cyphanta .

Figures

FIGURES 1 – 4. Adults. 1. Platychasma elegantula sp. nov. Holotype, Guangxi, China, 21 July 2007, leg. L. Chen; 2. Platychasma elegantula sp. nov. Paratype, Guangxi, China, 4 May 2007, leg. L. Chen; 3. Platychasma virgo Butler, Honshu, Japan, 3 May 2004, leg. M. Owada; 4. Cyphanta xanthochlora Walker, Yunnan, China, 21 July 2006, leg. M. Wang and X. Fan.

FIGURES 5 – 7. Male genitalia. 5. Platychasma elegantula sp. nov. Holotype, Mao’ershan, Guangxi, China, 21 July 2007, leg. L. Chen; 6. Platychasma virgo Butler, Honshu, Japan, 1 May 1986, leg. K. Umetsu (Genitalia slide, SS- 5837, in National Science Museum, Tokyo, Japan); 7. Cyphanta xanthochlora Walker, Yunnan, China, 21 July 2006, leg. M. Wang and X. Fan.