Cyana butyracea Volynkin & Černý, 2019

Volynkin, Anton V. & Černý, Karel, 2019, Three new species of Cyana Walker, 1854 from Indochina and China (Lepidoptera, Erebidae, Arctiinae, Lithosiini), Zootaxa 4586 (2), pp. 338-350 : 340-341

Cyana butyracea Volynkin & Černý , sp. n.

( Figs 9, 10 , 26, 27 )

urn:lsid:zoobank.org:act:37BA6B72-4CD0-4131-9B6F-BFFF92B5B2BF

Type material. Holotype ( Figs 9 , 26 ): ♂, “ Nord-Vietnam [North Vietnam], Tam Dao (Sek. Wald [secondary forest]), 60 km NW Hanoi, 1200 m (21.34’ N 105.20 ’E), 1.–5.V.1993, leg. Sinajev & Simonov”, slide ZSM Arct. 112/2017 ♂ Volynkin (Coll. MWM/ ZSM).

Paratypes: VIETNAM: 1 ♂, same data as in the holotype ( Coll. MWM/ ZSM) ; 2 ♂, N Vietnam, 16[00]– 1800 m, Mt. Fan-si-pan ( West ), Cha-pa , sec. forest, 22.20’ N 103.40 ’E (cult.) IV.1995, leg. Sinjaev & local collectors (Coll. MWM/ ZSM) ; 2 ♂, S Vietnam, Kon Tum Prov., Dac Glei , 15°07’N 107°42’E, h= 700 m, 8.VIII.1996, leg. Siniaev & Afonin (Coll. MWM/ ZSM) ; 4 ♂, South Vietnam, Bao Loc (sec. forest), Rung Cat Tien , 1500 m (11.32’ N 107.48 ’E), 10.–20.XII.1992, leg. Sinajev & Simonov”, slide ZSM Arct. 113/2017 ♂ Volynkin (Coll. MWM/ ZSM).

Diagnosis. Cyana butyracea sp. n. ( Figs 9, 10 ) is similar externally to the narrow-lined specimens of C. intercomma (widespread in Malay Peninsula, Thailand, Laos, Cambodia and Yunnan Prov. of China) ( Černý & Pinratana 2009; Bayarsaikhan & Bae 2016) ( Figs 11–16 ) and C. moelleri ( Figs 5–8 ), but can easily be distinguished from them by its pale butter-yellow forewing coloration and small discal spot. The forewing pattern of the new species also resembles that of C. bacilla Fang, 1992 ( Figs 17–18 ) known from SE China and Laos, but in the latter the forewing coloration is white, the forewing pattern elements are red (those are dark yellow in C. butyracea sp. n.), the antemedial line is straight (that is slightly wavy in C. butyracea sp. n.), the hindwing is pale red (that is pale butter-yellow in C. butyracea sp. n.), and the male genitalia structure is principally different ( Figs 31 , 38 ). The male genitalia structure of the new species ( Figs 26, 27 ) is most similar to those of C. intercomma ( Figs 28–30 ) by the shape of valva and the vesica structure, but differs by its slightly broader valva, slightly larger sclerotised crest of the medial costal plate of valva, and weaker subapical dentation of the aedeagus. In comparison to that of C. intercomma , the vesica of C. butyracea sp. n. lacks subapical and basal ventral clusters of spinules; in addition, the dorsal diverticulum of C. butyracea sp. n. bears longer cluster of spinules stretching along its inner margin, whereas in C. intercomma that is bunch-like and situated apically.

Description. Adult ( Figs 9, 10 ). Forewing length 14–15 mm in males (14 mm in the holotype). Male antennae weakly ciliate. Head white. Thorax white, tegulae and patagiae encircled by orange hairs. Abdomen white with slight admixture of ochreous scales distally. Forewing ground color pale butter-yellow; transverse lines orange; subbasal line wavy, broadened at costa; antemedial line wavy; postmedial line oblique, strongly narrowed opposite the cell, with admixture of black scales near costa; subterminal line broad, crescent-like curved; two large black spots in the cell: round inner and reniform outer; orange stroke on costa opposite the outer reniform black spot. Cilia pale butter-yellow. Hindwing ligth butter-yellow; discal spot absent. Male genitalia ( Figs 26, 27 ). Uncus dorso-ventrally flattened, short, narrowly arrowhead-shaped, its basal third connected to tuba analis. Tuba analis broad; scaphium not developed; subscaphium as broad setose field. Tegumen narrow, shorter than valvae. Juxta moderately sclerotised, trapezoidal, with round short lower concavity. Vinculum robust, U-shaped. Valva broad and elongated; costal margin slightly curved medially; medial costal plate with a long and very short plate-like sclerotised crest; valva apex broad and rounded; sacculus narrow, heavily sclerotised, its distal process robust, slightly curved dorsally, pointed apically, shorter than distal lobe of valva. Aedeagus tube-like, straight, with heavily sclerotised subapical area bearing numerous small denticles. Vesica globular, membranous, with several diverticula: four short and granulated diverticula medially; long and finger-shaped, membranous dorsal diverticulum with a long cluster of robust spinules laterally; in medial part of vesica a small spinula may be present.

Female unknown.

Distribution. Cyana butyracea sp. n. is to date, found in North and South Vietnam (Provinces Vinh Phuc, Lao Cai, Kon Tum and Dong Nai).

Etymology. ‘Butyracea’ means ‘buttery’ in Latin. The specific epithet refers to the unusual pale butter-yellow forewing coloration of the new species.

Figures

FIGURES 9–16. Cyana spp.: adults. 9, C. butyracea, holotype ♂, N Vietnam (MWM/ZSM); 10, C. butyracea, paratype ♂, S Vietnam (MWM/ZSM); 11, C. intercomma, paratype ♂, W Thailand (CKC); 12, C. intercomma, paratype ♂, N Thailand (CKC); 13, C. intercomma, paratype ♂, S Thailand (CKC); 14, C. intercomma, ♂, Malay Peninsula (MWM/ZSM); 15, C. intercomma, ♂, China, Yunnan (MWM/ZSM); 16, C. intercomma, paratype ♀, W Thailand (CKC).

FIGURES 26–28. Cyana spp.: male genitalia. 26, C. butyracea, holotype, N Vietnam, slide ZSM Arct. 112/2017 Volynkin; 27, C. butyracea, holotype, S Vietnam, slide ZSM Arct. 113/2017 Volynkin; 28, C. intercomma, paratype, W Thailand, slide AV3821 Volynkin.

FIGURES 1–8. Cyana spp.: adults. 1, C. artemis, holotype ♂, N Vietnam (MWM/ZSM); 2, C. artemis, paratype ♂, China, Guangxi (MWM/ZSM); 3, C. artemis, paratype ♂, N Thailand (CKC); 4, C. artemis, paratype ♀, N Thailand (CKC); 5, C. moelleri, holotype ♂, NE India (©NHMUK); 6, C. moelleri, ♂, NE India (MWM/ZSM); 7, C. moelleri, ♂, N Nepal (MWM/ ZSM); 8, C. moelleri, ♀, NE India (MWM/ZSM).

FIGURES 17–22. Cyana spp.: adults. 17, C. bacilla, ♂, C Laos, Khammouan Prov. (CKC); 18, C. bacilla, ♀, C Laos, Khammouan Prov. (CKC); 19, C. kucheri, holotype ♂, N Vietnam (MWM/ZSM); 20, C. kucheri, paratype ♀, N Vietnam (MWM/ZSM); 21, C. gazella, ♂, N Vietnam (MWM/ZSM); 22, C. gazella, ♀, N Thailand (CKC).

FIGURES 29–31. Cyana spp.: male genitalia. 29, C. intercomma, Malay Peninsula, slide MWM 34532 Volynkin; 30, C. intercomma, China, Yunnan, slide MWM 34535 Volynkin; 31, C. bacilla, C Laos, slide MWM 34567 Volynkin.

FIGURES 35–40. Cyana spp.: female genitalia. 35, C. artemis, paratype, N Vietnam, slide MWM 34525 Volynkin; 36, C. moelleri, E Nepal, slide ZSM Arct. 108/2017 Volynkin; 37, C. intercomma, paratype, W Thailand, slide AV4663 Volynkin; 38, C. bacilla, C Laos, slide MWM 34568 Volynkin; 39, C. kucheri, paratype, N Vietnam, slide ZSM Arct. 79/2017 Volynkin; 40, C. gazella, N India, slide MWM 34493 Volynkin.