Microlithosia laosana Bayarsaikhan & Bae, 2018

Bayarsaikhan, Ulziijargal, Lee, Dong-June & Bae, Yang-Seop, 2018, Genus Microlithosia (Lepidoptera, Erebidae, Arctiinae) in Laos, with the description of a new species, Zootaxa 4420 (4), pp. 502-508 : 503

Microlithosia laosana Bayarsaikhan & Bae , n. sp.

( Figs. 1 , 4 )

Type materials. Holotype: 1 ♂, Laos, Prov. Xieng Khouang, Ban Tha (N19˚43′0.70″, E103˚35′24.20″, Alt : 1204 m), 30.VI.2017 (Y.S. Bae, S.M. Na, D.J. Lee, J.H. Ko and T.K. Lee), Gen. Slide No. INU ˗1846L . Paratypes (4 ♀): Laos. 1♀, Prov. Bolikhamsai, Phou Khao Khouay NP. (N18˚30′11.37″, E102˚58′05.52″, Alt : 648 m), 9.XI.2015 (Y.S. Bae, B.S. Park, S.M. Na, J.W. Kim and D.J. Lee), Gen. Slide No. INU ˗1817L ; 1 ♂, Prov. Bolikhamsai, Phou Khao Khouay NP. (N18˚28′25.28″, E103˚05′6.11″), 1.IV.2016 (Y.S. Bae, B.S. Park, S.M. Na, J.W. Kim and D.J. Lee), Gen. Slide No. INU ˗1832L ; 1 ♂, Prov. Xieng Khouang, Ban Tha (N19˚44′50.20″, E103˚37′28.10″), 29.VI.2017 (Y.S. Bae, S.M. Na, D.J. Lee, J.H. Ko and T.K. Lee), Gen. Slide No. INU ˗1845L ; 1 ♂, Prov. Xieng Khouang, Ban Tha (N19˚44′50.20″, E103˚37′28.10″), 1.VII.2017 (Y.S. Bae, S.M. Na, D.J. Lee, J.H. Ko and T.K. Lee), Gen. Slide No. INU ˗1847L.

Diagnosis. This species is similar to members of shaowuica- species group by general appearance, which including: Microlithosia shaowuica Daniel , M. umbripuncta (de Joannis) , and M. nanlingica Dubatolov, Kishida & Wang. All species of this group have the forewing with a discal and a costal dark spots, and roundly convex costal margin. However, M. laosana n. sp. is differs from members by having the slightly convex forewing costal margin, about 1/3 of apex, plus the dark discal and claviform spots, and diffused distal area ( Figs. 1–3 ; Daniel 1954: 135).

In male genitalia, all species of shaowuica- species group have asymmetrical distal and basal saccular process and vesica with field of small spines. On its turn, M. laosana Bayarsaikhan & Bae , n. sp. presents symmetrically branched distal saccular processes and aedeagus with a bundle of slender spines and field of short spines ( Figs. 4– 6 ; Daniel 1954: 135, Abb. 97).

Description. Adult ( Fig. 1 ). Length of forewing 8˗10 mm. Head and thorax yellowish brown. Ground color of forewing yellow brownish, costal margin slightly convex about 1/3 of apex, a clear dark discal and a diffuse dark claviform spots; cilia pale yellowish. Hindwing white yellowish; cilia as in forewing. Abdomen pale, with yellowish tuft.

Male genitalia ( Fig. 4 ). Uncus slender, hook-shaped, with small spine at tip, with almost same length of tegumen; cucullus tapering to apex, shark dorsal fin-shaped; distal saccular process slender, curved downwards, with two asymmetric branch, reaching apex of valvae; basal saccular process stout, finger-shaped, bearing stout setae throughout its length, and with an apical spine, left basal saccular process twice longer than right; juxta domeshaped; aedeagus short, stout, with a long medial process; vesica with a bundle of slender spines and field of short spines.

Female unknown.

Distribution. Laos (Ban Tha, Prov. Xieng Khouang; NP. Phou Khao Khouay, Prov. Bolikhamsai).

Etymology. The species is named the country of type locality ( Laos).

Figures

FIGURES 1–3. Adults of genus Microlithosia spp. form Laos. 1. M. laosana sp. n., holotype, male, Laos. 2. M. umbripuncta, male, Laos. 3. M. nanlingica, male, Laos.

FIGURES 4–6. Male genitalia of genus Microlithosia spp. from Laos. 4. M. laosana sp. n., Laos (INU˗1846L, holotype). 5. M. umbripuncta, Laos (INU˗1827L). 6. M. nanlingica, Laos (INU˗1819L).