Diduga nigridentata Bayarsaikhan & Bae, 2019

Bayarsaikhan, Ulziijargal & Bae, Yang ˗ Seop, 2019, Four new and one newly recorded species of Diduga Moore, [1887] (Lepidoptera, Erebidae, Arctiinae) from Vietnam, with redescription of the little known species Diduga haematomiformis van Eecke, 1920, Zootaxa 4624 (3), pp. 365-376 : 373-375

Diduga nigridentata Bayarsaikhan & Bae , n. sp.

( Figs 7 , 13 )

Type materials. Holotype: 1 ♂, Vietnam, Prov. Hanoi, BaVi N.P., 19.VII˗5.VIII.2010 (700 m), (Y.S. Bae & X.V. Le), Gen. Slide No. INU˗ 1915V. Paratypes. (3 ♂) Vietnam : 1 ♂, Prov. Vinh Phuc, Tam Dao N.P., 14.VIII.2005 (Y.S. Bae, J.H. Bae & P.V. Nha leg.), Gen. Slide No. INU˗ 1929V ; 2 ♂, Prov. Ninh Binh, Cuc Phuong N.P., 24.IV.2006 (Y.S. Bae) , Gen. Slide No. INU˗ 1926V, 1935V.

Diagnosis. By the male genitalia, three species of Diduga , D. spinosusa Bucsek, 2012 ( Bucsek 2012: 24, Mal022) and D. cucphuonga Dubatolov & Bucsek, 2016 ( Dubatolov & Bucsek 2016: 237, Fig 37) with strong spines on the apex of valva, but significantly different from allied species: valva with two asymmetric, stout, basal projections of costal margin (in D. spinosusa and D. cucphuonga , its absent), and asymmetric valva with two dif- ferent sized apical spines (in D. spinosusa , more than five apical spines almost same sized to each other and 2˗3 times longer than D. nigridentata . In D. cucphuonga , four apical spines different sized to each other and shorter than D. nigridentata ); aedeagus vesica with one stout, spine˗shaped cornutus and one bundle of short spines (In D. spinosusa , with two bundles of short spines and weakly sclerotized plate. In D. cucphuonga , with several spines inside (in original description)).

Description. Adult ( Fig 7 ). Length of forewing 5.5– 6 mm in male. Head, patagium and tegula deep yellow. Thorax dark brown. Forewing ground color dark brown, with broad, deep yellow costal margin, which hind bor- der broadly waved; with row of small, dark brown dots or patches from basal of costa to tornus; cilia deep yellow. Hindwing ground color light brown; cilia light brown. Abdomen brown, except deep yellow ventral, with deep yellow anal tuft in male. Male genitalia ( Fig 13 ). Uncus slender, almost 90° bent to inward, with a hook˗shaped, small apical spine. Tegumen weakly sclerotized, triangular in apical half and roundly broad in basal half. Valva stout, asymmetric, left valva broader than right, with asymmetrical apical processes: in left valva, rectangular apical prominence weakly sclerotized, with two different sized, weakly waved spines, which upper spine (almost same length with uncus) almost four times longer than lower one; in right valva, excavate in between prominence weakly sclerotized, with three different sized spines, which almost straight, strongly sclerotized, ventral spine (0.5 times shorter than left upper spine) almost four times longer than strongly sclerotized lower angle’s one, and six times longer than weakly sclerotized medial one; basal projections of valva asymmetric (right one more stout), strongly sclerotized, weakly curved apically, with a bundle of small apical spines. Juxta sclerotized, tubular. Saccus “U”˗shaped. Aedeagus slender, strongly waved and vesica with one stout, spine˗shaped cornutus and one bundle of short spines. Female genitalia. Unknown.

Distribution. Vietnam (Hanoi, Ninh Binh, Vinh Phuc Prov.).

Etymology. The specific epithet is derived from the Latin “ nigri- ” meaning “black” and “ dentatus ” meaning “with teeth”, refers to the forewing with dentate blacking marking.

Figures

FIGURES 3–7.Adults of genus Diduga spp. from Vietnam. 3a. D. alternota, male (INU˗1934V). 3b ditto, female (INU˗1930V). 4a. D. hanoiensis n. sp., male (holotype, INU˗10012V). 4b. ditto n. sp., female (paratype, INU˗10015V). 5a. D. bayartogtokhi n. sp., male (holotype, INU˗1923V). 5b. ditto n. sp., female (paratype, INU˗10014V). 6a. D. quinquicornuta n. sp., male (holotype, INU˗1918V). 6b. ditto n. sp., female (paratype, INU˗10016V). 7. D. nigridentata n. sp., male (holotype, INU˗1915V).

FIGURES 12–13. Male genitalia of genus Diduga spp. from Vietnam. 12. D. quinquicornuta n. sp. (holotype, INU˗1918V). 13. D. nigridentata n. sp. (holotype, INU˗1915V).