Loxoneptera albicostalis Swinhoe, 1906

Xiang, Lanbin, Chen, Kai & Zhang, Dandan, 2021, Revision and phylogeny of the genus Loxoneptera Hampson, 1896 (Lepidoptera, Crambidae, Pyraustinae), based on morphology and molecular data, ZooKeys 1036, pp. 75-98 : 75

Loxoneptera albicostalis Swinhoe, 1906 Figs 4 , 14 , 16

Loxoneptera albicostalis Swinhoe, 1906: 415.

Material examined.

Type material. Type ♂, Padang, W. Sumatra, Pyralidae Brit. Mus. Slide No. 9753 (NHMUK).

Other material examined. China. Yunnan: 1♂, Jingpo Village, Nabang, Yingjiang Country , 24.71°N, 97.39°E, alt. 231 m, 2.VIII.2013, leg. Teng Kaijian et al., genitalia slide no. ZDD12108 (NKU) .

Diagnosis.

In appearance, Loxoneptera albicostalis is extremely similar to L. crassiuncata and Eumorphobotys horakae Chen & Zhang, 2018 in the wing shape, the clean reddish brown forewing and the dark brown hindwing, but can be distinguished by the whiter costa of both wings, a group of dark brown scales on the posterior margin of forewing, and a group of scales on each side of the 5th abdominal segment in male. The underside of forewing in L. albicostalis is smoky brown, while that of E. horakae is pale yellow from anterior margin of cell to posterior margin. The male genitalia resemble that of L. crassiuncata but can be differentiated by the shorter and stouter uncus, the relatively longer and slender dorsal projection of transtilla, nearly triangular dorsal sella, the long and hook-shaped process of the ventral sella, as well as the absence of the spine-shaped cornutus in phallus.

Redescription.

Head. Frons brown. Vertex brown, mixed with some yellow erected scales. Labial palpus dark brown, with white scales on ventral side. Maxillary palpus brown. Antennae yellowish brown. Thorax. Dorsal side, patagia and tegula brown, ventral side grey white. Legs pale yellow to grey white; hindleg basal outer spur 1/5 of basal inner spur. Wings. Wingspan 32.0-36.0 mm. Forewing wide, reddish brown, without pattern; costal area white, mixed with pale brown scales at apex; termen straight; a small triangular indentation presented on the 1/3 of posterior margin in male, and with a group of black-brown scales; fringe white, with basal 1/4 black-brown. Hindwing black-brown, costa area pale yellow; a triangular patch presented near the posterior angle of cell, densely covered with pale brown scales; fringe black-brown. Underside smoky dark brown on forewing, and pale brown on posterior margin area. Abdomen. Dorsal side black-brown, ventral side grey white; abdominal segment V with a group of dark scales on each side in male; sternite VIII in male slightly sclerotised with two pointed anterolateral processes.

Male genitalia (Fig. 16 ). Uncus wide and short, distally broadly rounded, with few hair-like setae. Saccus rounded. Dorsal projection of transtilla relatively thick and slightly curved, ~ 1/3 length of costa, distally bearing hairs longer than projection. Valvae with dorsal margin slightly straight, ventral margin sinuated, apex narrowly rounded; costa narrow; dorsal sella membranous with several setae, nearly triangular; ventral sella with a long, hook-shaped, and sclerotised process; dorso-distal sella bearing a short sclerotised process distally; sacculus broad, extended dorsad a triangular protrusion in middle. Juxta shield-shaped, middle part weakly sclerotised. Phallus slowly narrow to end, vesica mostly granulated.

Female genitalia. Unknown.

Distribution.

China (Yunnan), Indonesia (Sumatra), Malaysia.

Remarks.

The forewing colour of the type material of Loxoneptera albicostalis is pale yellow tinged with some reddish brown scales and differs from the specimen collected in China. No obvious difference could be found in the male genitalia between the type specimen and the Chinese specimen.

Figures

Figures 2 - 9. Adults of Loxoneptera spp. 2 L. hampsoni nom. nov., male (Tibet) 3 L. hampsoni nom. nov., female (Hainan) 4 L. albicostalis, male (Yunnan) 5 L. crassiuncata sp. nov., paratype, male (Yunnan) 6 L. carnealis, male (Yunnan) 7 L. triangularis sp. nov., holotype, male (Yunnan) 8 L. rectacerosa sp. nov., holotype, male (Yunnan) 9 L. medialis, male (Guangdong). Scale bars: 5.0 mm.

Figures 14 - 19. 14 The sternite VIII in male of L. albicostalis 15 - 19 Male genitalia of Loxoneptera spp. 15 L. hampsoni nom. nov., Hainan (genitalia slide no. SYSU 0929) 16 L. albicostalis, Yunnan (genitalia slide no. ZDD 12108) 17 L. crassiuncata sp. nov., Yunnan (genitalia slide no. FCEL 0010) 18 L. carnealis, Guizhou (genitalia slide no. SYSU 0165) 19 L. triangularis sp. nov., Yunnan (genitalia slide no. FCEL 0004). Scale bars: 1.0 mm.