Diduga taiwana Bayarsaikhan & Bae, 2021

Bayarsaikhan, Ulziijargal, Heppner, John B., Kwon, Hyung-Wook & Bae, Yang-Seop, 2021, Review of the genus Diduga Moore (Lepidoptera, Erebidae, Arctiinae) of Taiwan with descriptions of two new species, Zootaxa 5032 (2), pp. 216-224 : 217-219

Diduga taiwana Bayarsaikhan & Bae , sp. n.

( Figs 1 , 3 , 5 , 7 )

Type materials. Holotype: 1 ♂, Taiwan , Nantou Co., Yu-Chi , Wu-Cheng Hwa-Lung , Ca 600m, 18–19.XI.1997 (YS Bae & KT Park), Gen. Slide No. INU-1908 T (Coll. INU) . Paratypes. (24 ♂, 15 ♀) TAIWAN : 1 ♂, Taoyuan Co., Upper Palin (2260m), 11–12.VII.1996 (KT Park et JS Lee), Gen. Slide No. INU-1911 T ; 1 ♀, Taipei Co., Fushan (650m), 14–15.X.2000 (KT Park et MS Go), Gen. Slide No. INU-1907 T (Coll. INU) . 1 ♂, Nantou Co., Lushan-spa , 29.VII.1985 (Y. Kishida leg.), Gen. Slide No. CYKJ-10030 T (Coll. Mr. Kishida) . 7 ♂, 1 ♀, Ilan Co., Chilan ( Tuchan ) (480m), 1–2.VII.1982 (J.B. Heppner), adult photo 14602, Gen. Slide No. JBH 3904m ; 1 ♀, same site, 15–17.X.1984 (JBH & HYW); 7 ♂, 2 ♀, Kaohsiung Co., Shanpin For. Sta. , 23.IV–3. V.1989 (JBH & HYW), Gen. Slide No. JBH-3939f, adult photos 14598f, 14599m ; 1 ♂, 2 ♀, Pingtung Co., Taiyuan (200m), 8.III.1990 (J.B. Heppner) ; 2 ♂, 4 ♀, Taichung Co., Chingshan (1100m), 27.III–1.IV.1990, adult photo 14600m (JBH & HYW) ; 2 ♂, same site, 8–11. V.1989 (JBH & HYW); 2 ♂, 4 ♀, same site, 31.VIII–4.IX.1988 (JBH & HYW); 1 ♂, Taipei Co., Mayueyuan (990m), 16–17. V.1989 (JBH & HYW), adult photo 14605m , Gen. Slide No. JBH-3907 (Coll. second author).

Diagnosis. The wing pattern of this species is hardly distinguishable from many others of the genus Diduga . The male and female genitalia structures of the new species are similar with D. quinquicornuta ( Bayarsaikhan & Bae 2019: fig. 12), D. hainanensis ( Bayarsaikhan et al. 2020a: fig. 14), and D. chebalinga ( Zhao & Han 2020: fig. 16), but can be distinguished from the latter by the apex of left valva with just two different sized processes and short (almost same length with uncus) basal saccular process of left valva triangular, with diversely dentate margin; and the right valva with three diverse sized and shaped processes, among them stout, entire costal one cow horn-shaped (weakly curved); by the female genitalia of this new species significantly different from allied species by a larger right spur of ostial plate with strongly dentate margin and a smaller left spur covered with small spines. In D. quinquicornuta , the apex of left valva with four different sized processes and basal saccular process long (more than 3x longer than uncus), slender, waved, and the right valva with four diverse sized and shaped processes, among them stout, serrate costal one almost straight in the male genitalia; in female genitalia, a left spur of ostial plate larger, heavily covered with small spines, and a smaller right one blunt, partly covered with small spines. In D. hainanensis , the apex of the left valva with four different sized processes (apical one bifurcated) and basal saccular process long (more than 4x longer than uncus), straight, and right valva with two large diverse sized and shaped processes, among them rectangular costal one dentate in the male genitalia; in female genitalia, the ostial plate, covered with small spines wholly, and irregularly arch-shaped right and strongly waved left spurs. In D. chebalinga , the left cucullus is sclerotized, spoon-shaped with two short, rectangular, apical spur and the basal saccular processes asymmetrically bifurcated, the lower one about 6x shorter than the longer one (the longest one 2x longer than uncus), straight, and the right valva with four diverse sized and shaped processes, among them the rectangular costal one dentate; in female genitalia, the ostial plate, covered with small pines wholly, and irregularly blunted and with small spurs.

The pregenital complex of the male abdomen ( Fig. 7 ) remains unclear as to function and is unique among the Diduga species known thus far, contrasting also with the simple lyre-like forked structure of D. nantouensis sp. n. ( Fig 8 ). The female has the pregenital abdominal segment simple and without any specialized structure, contrasting with the pouched structures (pheromone pouches?) of D. nantouensis sp. n. ( Fig 9 ).

Description. Adult ( Figs 1a, 1b ). Length of forewing 6–7 mm in males (n=25), 7 mm in females (n=15). Head, patagium, and tegula deep yellow. Thorax dark brown. Forewing ground color dark brown, with broad, deep yellow costal margin, which hind border broadly waved; with a row of small, dark brown dots or patches from basal of costa to tornus; cilia deep yellow, mixed with dark brown scales. Hindwing ground color pale gray; cilia pale gray. Abdomen dark brown, except deep yellow ventral, with deep yellow anal tuft in. Male genitalia ( Fig 3 ). Uncus stout, bent, apex excavated, which upper angle curved, with a small spine and lower angle roundly blunt, weakly covered with setae. Tegumen pyriform, heavily sclerotized apical half. Valva asymmetric: tapering left valva with two same-sized (slightly shorter than uncus) processes, stout apical one with triangular outline and lower one slen- der, thorn shaped; costal margin with a horn-shaped basal process (slenderer and shorter than right valva’s process); cucullus rounded, partly sclerotized, heavily covered with setae apically; triangular basal saccular process with diversely dentate margin; short, stout right valva with three diverse sized and shaped processes, which first costal one stout, entirely cow-horn shaped, the medial short one with a triangular outline, and lower one slender, spoon-shaped, 2x longer than medial process; membranous cucullus long (0.5x longer than left cucullus), spoon-shaped, heavily covered with setae apically; basal saccular process short thorn shaped. Juxta elongated. Saccus “V” shaped. Aedeagus stout, weakly sclerotized, apex strongly curved, with slender, waved spines and vesica without cornutus and scobination. Pregenital plate ( Fig 7 ) with an extremely complicated complex of sclerotized parts, with two anterior medial appendages and a median posterior projecting structure from a basal half horseshoe-like anterior arch.

Female genitalia ( Fig 5 ). Papillae anales are weakly covered with setose. Apophysis posterioris about 0.5 times longer than apophysis anterioris, and both apophysis slender. Asymmetrical ostial plate strongly sclerotized: archshaped left spur half of length of right one, covered with small spines wholly and irregularly triangular right spur strongly dentate margin, weakly covered with small spines. Ductus bursae tubular, membranous, weakly wrinkled. Corpus bursae irregularly ovoid, heavily covered with dense spinulose scobination in proximal half.

Etymology. Names after the island of Taiwan where the type locality belonging.

Figures

FIGURE 9. Female pregenital abdomen of Diduga nantouensis sp. n., showing ventral lateral pouches. 9a. 4–5th abdominal segment (JBH–3940f, Tienchih, Kaohsiung Co., Taiwan). 9b. 1–4th abdominal segment (INU–1912m, Wulai (550m), Taipei Co., Taiwan).

FIGURES 1–2. Adults of genus Diduga spp. from Taiwan. 1a. D. taiwana sp. n., male (holotype, INU–1908Taiwan). 1b. ditto, female (paratype, INU–1907Taiwan). 2a. D. nantouensis sp. n., male (holotype, INU–1910Taiwan). 2b. ditto, female (paratype, INU–1912Taiwan).

FIGURES 3–4. Male genitalia of genus Diduga spp. from Taiwan. 3. D. taiwana sp. n. (holotype, INU–1908Taiwan). 4. D. nantouensis sp. n. (holotype, INU–1910Taiwan).

FIGURES 5–6. Female genitalia of genus Diduga spp. from Taiwan. 5. D. taiwana sp. n. (paratype, INU–1907Taiwan). 6. D. nantouensis sp. n. (paratype, INU–1912Taiwan).

FIGURES 7–8. Male pregenital abdomen of genus Diduga spp. from Taiwan. 7. D. taiwana sp. n. (JBH–3902m, Chingshan, Taichiung Co., Taiwan). 8. D. nantouensis sp. n. (JBH–3901m, Shanpin For. Sta., Kaohsiung Co., Taiwan).