Thysanoplisna Volynkin 2023

Genus Thysanoplisna Volynkin, 2023 Thysanoplisna Volynkin, 2023, Ecologica Montenegrina, 69: 55. Type species: Lithosia brevimacula Alphéraky, 1897, by original designation. Note. The genus is herein re-characterised following the genitalia terminology suggested by Volynkin (2024). Diagnosis. Thysanoplisna (Figs 1–36) is morphologically most similar to the recently described Caliginoptyx (Figs 37, 38) and Medioptyx (Figs 39, 40) but superficially differs in the longer distal section of the forewing (between the cell and the outer margin), the ochreous grey or ochreous brown forewing ground colour (it is pale brownish-grey in Caliginoptyx and bright ochreous yellow in Medioptyx), and the short trapezoid or rounded medial black spot, which is more similar to Teulisna Walker, 1862 s. str. and Witteulisna Volynkin, 2020 (illustrated by Volynkin 2020), whereas it is shorter, diffuse and greyish-brown in Caliginoptyx and considerably longer and occupying most of the forewing in Medioptyx. The male genital capsule structure of Thysanoplisna (Figs 41–53) is characterised by the combination of the following features. (1) In the conjuga, the processus momenti is weakly sclerotised while the tendon is thick and heavily sclerotised and performs a skeletal function (vs. in Caliginoptyx (Fig. 54) and Medioptyx (Fig. 55), the conjuga is formed by the equally heavily sclerotised processus momenti and tendon). (2) The juxta consisting of two thin rod-like lateral plates, which are dorsally connected by the thin bridge and fused with two rod-like lobes of the caulis stretching laterally along the anterior (cranial) wall of the juxtal fold. (3) The membranous anellus. The juxta and anellus structures of Thysanoplisna are similar to Caliginoptyx whereas in Medioptyx, the dorsal section of the juxta is conical and well-sclerotised, and the anellus bears two broad ventro-lateral sclerotised plates. The vesica structure of Thysanoplisna is similar to Caliginoptyx with its sub-ejaculatorial section situated basally, but that of Thysanoplisna lacks the diverticula. Unlike in Thysanoplisna, the vesica ejaculatorius of Medioptyx originates distally. The female genitalia of Thysanoplisna (Figs 56–68) are most similar to Caliginoptyx (Fig. 69) but differ in the flat and evenly sclerotised ductus bursae (it is less dorso-ventrally flattened and has postero-lateral membranous areas in Caliginoptyx), the compact, elliptical or rounded signum bursae (it is markedly larger and ribbon-like in Caliginoptyx), and the ventrally situated appendix bursae (vs. dorsal position in Caliginoptyx). Compared to Medioptyx (Fig. 70), the female genitalia of Thysanoplisna have a medially constricted corpus bursae with a posterior section having a gelatinous enlargement protruding ventrally or laterally, and an anterior section bearing a signum, whereas in Medioptyx, the corpus bursae is sack-like and lacks both the posterior enlargement and the signum bursae. Note. Species of the genus significantly vary in their size and the size and shape of the forewing medial spot within the same population. Distribution. Species of the genus are known from northern Mainland Southeast Asia (Vietnam), mainland China and the island of Hainan, but absent from the island of Taiwan. Species content of Thysanoplisna The Th. signata species-group – Th. brevimacula (Alphéraky, 1897) – Th. signata (Walker, 1854) – Th. grandimacula sp. nov. – Th. minuta sp. nov. – Th. monotona sp. nov. – Th. bachma sp. nov. – Th. suffusa sp. nov. The Th. directa species-group – Th. directa (Leech, 1899), stat. rev. – Th. tenebrosa sp. nov. – Th. hoenei sp. nov. The Th. anomala species-group – Th. anomala (Volynkin, 2021)