Simplicia Guenée, 1854

Raha, Angshuman, Sanyal, Abesh Kumar & Singh, Navneet, 2025, On the taxonomy of genus Simplicia Guenée, with a new species from India (Lepidoptera: Erebidae: Herminiinae), Zootaxa 5631 (3), pp. 451-474 : 458-459

Genus Simplicia Guenée, 1854

Simplicia Guenée, 1854 , Hist. nat. Ins., Spec. gén. Lépid., 8: 51. (TS: Herminia rectalis Eversmann, 1842 )

= Libisosa Walker, [1859] , List Spec. Lepid. Insects Colln Br. Mus., 16: 187. (TS: Libisosa butesalis Walker, [1859] )

= Culicula Walker, 1864 , J. Proc. Linn. Soc. (Zool.), 7: 178. (TS: Culicula bimarginata Walker, 1864 )

= Aginna Walker, 1865 , List Spec. Lepid. Insects Colln Br. Mus., 33: 1022. (TS: Aginna circumscripta Walker, 1865 )

= Nabartha Moore, [1885] , Lepid. Ceylon, 3 (2): 234. (TS: Bocana schaldusalis Walker, [1859] )

Taxonomic note

The members of the genus Simplicia are phenotypically very similar as they are mostly brownish or greyish having apparently similar wing fasciation. The differences between the species are visible mainly in the male antennae, overall size of adults, intensity of brown shading on the wings, curvature of the pale sub-marginal line on the forewing, and minutely in the conspicuousness, curvature and obliqueness of the ante-medial and post-medial lines on the wings. Although the antenna is ciliate, the arrangement of cilia on flagellomeres may be either uniform or fasciculate or a combination of both. The genus may be broadly divided into two groups based on the male antennae; in one group, the male antennae have a node with long scales at variable length; in other group, the males have simpler antennae without any node. The flagellomeres may too vary in size and shape with the central ones having stout spines on the inner side. The forelegs in male have relatively short and robust coxa in respect to other genera and tibial sheath associated with buff-brown tuft of hairs whose length varies depending on species. In some species this tibial tuft of hairs is present on all the legs. The forewing venation shows remarkable inter-specific variations rendering more stable characters of wing fasciae and male genitalia as diagnostics for the genus ( Prout 1929). Externally, Simplicia is best separable from other Herminiinae genera by the presence of a thin and pale sub-marginal line on the wings which on the hindwing is obtusely angled near the anal angle. In some species, this pale sub-marginal line on both wings is highlighted by the darkening of the ground colour immediately basal to it. The male genitalia have curved and elongated uncus with slender proximal half and laterally compressed, broad, often dorsally domed and apically acute distal half. Valva is typically tongue-like, sometimes very elongated ending in a slender, acute apex and with a spur of variable size at the distal end of the sacculus and usually a short apical or sub-apical spine on the costa. Aedeagus vesica is large, usually with large patch of coarse tuberose signa and short to moderate distal diverticulum of variable shape. The female genitalia have long, slender, typically sclerotized ductus bursae and bulbous corpus bursae whose basal half to two-thirds, usually has coarse tuberose signa.

The genus generally inhabits lowland to upper montane tropical forest habitats with annual precipitation of more than 2000 mm. The larvae are known to feed on leaf litters and sometimes on fresh leaves ( Holloway 2008). Larvae of several Bornean species are reported to forage on a range of plant families, like Amaranthaceae , Dipterocarpaceae , Euphorbiaceae, Gramineae etc., but without any information on the part of the plant or the condition they are being devoured ( Robinson et al. 2001).