Pyraustinae, Meyrick, 1890

Singh, Navneet, Ranjan, Rahul, Talukdar, Avishek, Joshi, Rahul, Kirti, Jagbir Singh, Chandra, Kailash & Mally, Richard, 2022, A catalogue of Indian Pyraloidea (Lepidoptera), Zootaxa 5197 (1), pp. 1-423 : 37-39

2.8. Pyraustinae

Diversity and distribution: the third largest subfamily in Crambidae and globally comprises 1,274 valid species in 172 genera (Nuss et al. 2003–2022, Léger et al. 2020), with 94 genera (52%) monotypic and only three genera with more than 50 species: Loxostege Hübner , Anania Hübner and Pyrausta Schrank (Nuss et al. 2003–2022). From India, 183 species in 53 genera are reported, representing 14.36% of the global species of Pyraustinae . 24 genera are known through single species only, 26 genera are reported by 10 species or less and three genera are reported by having more than 10 species: Crocidophora Lederer , Pyrausta Shrank , and Pagyda Walker ( Fig. 25 ). The subfamily is most diverse in the North East and central Himalaya, with fewer species in the remainder of the biogeographic zones ( Fig. 26 ).

Adult characters: generally, have the triangular forewings, long legs and a somewhat satiny appearance. The antennae are long and sometimes crossing the forewing apex. In both sexes, the third labial palpomere is well developed. The forewing in males often exhibits a retinacular hook. CuP of the forewing is absent or represented by a fold, and 2A and 1A form a large, closed loop. M 1 of the hindwing is often stalked with Rs, and the base of CuA is not pectinate. In the paired tympanal organ, the surface of the fornix tympani is recessed within the tympanic frame. In the genitalia, males have a conical uncus and a tegumen with a distinct sclerotisation pattern. The gnathos is almost rudimentary or lost. The valvae often exhibit a sclerotised process (sella) carrying strong hairs of different shapes (editum). The female genitalia usually exhibit an appendix bursae and a long, coiled ductus bursae. The signum is usually rhombical and broad, with the transverse axis longer than the longitudinal axis, it often exhibits distinct ridges (carinae) ( Marion 1952, Solis & Maes 2003, Mally et al. 2019).

Larval characters: according to Allyson (1981), last-instar larvae of Pyraustinae exhibit the following diagnostic characters: Posterior angle of frons extending to two-thirds or more of distance to occipital foramen, prothorax with two L setae, D- and SD-bearing pinacula never fused on metathorax, SD 1 bearing pinaculum always present on A2 and A7, distance of V1-V1 larger on A10 than on A9, latter with one L seta, L2 present on A1 to A8, proleg crochets bi- or triordinal, arranged in a complete or incomplete circle. These characters are shared with the sister group of Pyraustinae , the Spilomelinae ( Allyson 1984) .

Food plants: larvae feed on a variety of dicotyledonous plants, with the tribe Euclastini on Apocynaceae and Portentomorphini primarily on Phyllanthaceae ( Mally et al. 2019) .

Figures

FIGURE 25. Species diversity of Indian Pyraustinae genera.

FIGURE 26. Species diversity of Indian Pyraustinae in different biogeographic zones/zones.