Dentadra Dubatolov, Volynkin, N. Singh, Joshi & Černý, 2021

Dubatolov, Vladimir V., Volynkin, Anton V., Singh, Navneet, Joshi, Rahul & Černý, Karel, 2021, On the taxonomy of the Prabhasa / Zadadra generic complex with descriptions of two new genera and two new species (Lepidoptera, Erebidae, Arctiinae, Lithosiini), Zootaxa 4966 (5), pp. 519-534 : 521-522

Genus Dentadra Dubatolov, Volynkin, N. Singh, Joshi & Černý , gen. nov.

Type species: Prabhasa flavicosta Moore, 1878 .

Diagnosis. The wing pattern of the only species of the new genus ( Figs 1, 2 ) is similar to that of the genera Prabadra gen. nov. ( Figs 3–6 ), Chinasa ( Figs 7, 8 ) and Prabhasa ( Figs 9, 10 ) due to the presence of a mustard yellow streak along the forewing costa interrupted by the postmedial costal spot, but the male and female genitalia structures are unique among the known members of the subtribe Lithosiina . The male genitalia ( Figs 19, 20 ) are clearly different from those of other members of the Prabhasa / Zadadra generic complex ( Figs 21–32 ) and characterized by the combination of the following autapomorphic features: (1) the uncus is swollen, broadly triangular, bearing rounded lateral lobes, (2) the costa of valva is heavily sclerotized medially and distally and bears two processes that are asymmetrical: the left valva with broadly bifurcated process, while the right valva with single, reduced to a small, shortly dentate tubercle, (3) the ventral edge of the sacculus bears a row of various-sized thorn-shaped denticles, (4) the distal saccular process is short, flattened, plate-like, with irregularly dentate margins, fused with the distal end of the costa. Additionally, the aedeagus of the new genus is short and thick, whereas in other related genera it is narrow and elongate. The aedeagus vesica of Dentadra gen. nov. is armed with two clusters of robust, various-sized triangular cornuti, whereas in other genera, the vesica generally lacks sclerotized elements and only in Prabadra gen. nov. it bears a single narrow cornutus. The intervalval commissura of the new genus is short, connecting valvae basally only, like in Prabhasa , but the latter genus differs fundamentally from Dentadra gen. nov. by its structure of uncus, valva and ornamentation of vesica. The female genitalia of Dentadra gen. nov. ( Figs 33 ) differ clearly from those of the other genera ( Figs 34–38 ) by (1) the ductus bursae funnel-like with sclerotized and rugose lateral margins (whereas in other genera, it is narrow and flattened dorso-ventrally), (2) the presence of broad lateral subostial lobes connected to margins of ostium bursae by triangular apical processes (an autapomorphic feature), (3) the presence of a wide sclerotized dorsal plate with dentate anterior margin covering ductus bursae (an autapomorphic feature), (4) the broad, sack-like and weakly rugose corpus bursae (whereas in other genera, it is weakly membranous and lacking sclerotized elements except for Prabadra gen. nov. having a large dentate signum bursae), and (5) the short but broad, weakly rugose appendix bursae (whereas in other genera, it is narrowly conical and membranous).

Description. Adult. Forewing length 12–12.5 mm in males and 14–15 mm in females. Male antenna ciliate, female antenna filiform. Sexual dimorphism limited: in male ( Fig. 1 ), forewing less elongate, with cell bearing elongate area of androconial scales along the basal two thirds of vein R, and tip of abdomen covered in mustard yellow hair-like scales; in female ( Fig. 2 ), forewing lacking androconial scales, and abdomen monotonous brown. Body dark brown, frons mustard yellow. Forewing dark brown with blackish brown suffusion medially and subterminally; costal margin mustard yellow with dark brown postmedial spot and thin blackish outer edge in basal half; cilia mustard yellow. Hindwing monotonous dark brown. Male genitalia ( Figs 19, 20 ). Uncus swollen, broadly triangular, with rounded lateral lobes. Tegumen short, weak, dilated and fused apically at uncus. Vinculum short, weak, rectangular with rounded corners. Juxta weakly sclerotized. Intervalval commissura short, connecting approximately basal one fourth of valvae. Valva relatively short, lobe-like; costa heavily sclerotized medially and distally, bearing asymmetrical ventral processes: the left valva with broadly bifurcated process, while the right valva with single, reduced to a small, shortly dentate tubercle. Cucullus short, represented as short rounded protrusion of costa. Ventral edge of sacculus bearing row of various-sized thorn-shaped denticles; distal saccular process short, flattened, plate-like, with irregularly dentate margins, fused with distal end of costa. Aedeagus short and thick, its carinal plate short, broad, rounded, with dentate distal margin; main chamber of aedeagus vesica short but broad, nearly globular, bearing two clusters of robust, various-sized triangular cornuti; vesica ejaculatorius originates subbasally. Female genitalia ( Fig. 33 ). Papillae anales trapezoidal with rounded corners. Apophyses long and thin, apophyses anteriores longer than apophyses posteriores. Ostium bursae wide. Ductus bursae short, funnel-like with sclerotized and rugose lateral margins. 7 th sternite bearing wide lateral subostial lobes connected to margins of ostium bursae by triangular apical processes and broad sclerotized dorsal plate with dentate anterior margin covering ductus bursae. Sclerotized pockets of 7 th sternite short, broadly triangular with rounded tips. Corpus bursae broad, sack-like, weakly rugose. Appendix bursae short but broad, weakly rugose.

Etymology. The genus name is an aggregate of the Latin word ‘dentatus’ meaning ‘dentate’ and the genus group name Zadadra . The name refers to the strongly dentate margin of the sacculus of the type species. Gender feminine.

Figures

FIGURES 1–10. Lithosiina spp.: adults. Depositories of the specimens: 1, 2 and 9 in NHMUK (© The Trustees of the Natural History Museum); 3 and 8 in SZMN; 4 in NZCZSI; 5 and 6 in CKC; 7 and 10 in ZFMK.

FIGURES 19–22. Lithosiina spp.: male genitalia. The specimens are deposited in NHMUK (© The Trustees of the Natural History Museum).

FIGURES 33–38. Lithosiina spp.: female genitalia. Depositories of the specimens: 33 and 36 in NHMUK (© The Trustees of the Natural History Museum); 34 and 38 in CKC; 35 and 37 in MWM/ZSM.