Crambinae, Latreille, 1810

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 : 28-29

2.2. Crambinae

Diversity and distribution: worldwide, ranging from cold-temperate to tropical regions. Globally, the subfamily comprises 2,072 species in 175 genera (Nuss et al. 2003 – 2022, Léger et al. 2020). In India, 149 species in 40 genera are reported, representing 7.19% of the total global diversity of Crambinae . Of the 40 genera reported from India, 19 genera are known through single Indian species, 15 genera comprise two to 10 species in India, and the remaining six genera, Ancylolomia Hübner , Calamotropha Zeller , Charltona Swinhoe , Chilo Zincken , Eschata Walker and Glaucocharis Meyrick are known by more than 10 and fewer than 20 species ( Fig. 16 ). In India, the highest diversity of Crambinae is reported from North East, followed by the Deccan Peninsula, the West- and North West Himalaya, Western Ghats, the central Himalaya, the Semi-Arid, the Gangetic plain, and Coasts ( Fig. 17 ).

Adult characters: mostly of small to moderate size. With their longitudinally streaky patterns on the forewings that are wrapped closely around the body in resting position, they generally mimic grass foliage ( Landry 1995, Holloway et al. 2001). The forewing termen is often notched. The discocellular spots in the hindwing are usually incomplete. The labial palps are long and porrect, and the maxillary palps have distally expanded scaling. In the forewing, the stem of CuA mostly exhibits a pecten of erect setae. In the male genitalia, the uncus and gnathos are distant from vinculum, juxta and valvae. The gnathos bears lateral arms articulating with the junction of tegument and uncus. The valvae usually exhibit a sclerotized and process-bearing costal region and sacculus. The phallus is medially attached to the juxta, which is a synapomorphy for the subfamily. In the female genitalia, signa are absent, but sometimes present as an inconspicuous group of spicules ( Munroe & Solis 1999).

Larval characters: in the head, the adfrontals usually reach maximally half of the coronal suture, AF2 above the furcation of the epicranial suture, lower than P2. Stemma 5 is dorsocaudal or caudal of stemma 6, and stemmata 4–6–5 form an acute or a right angle. O3 is below the line of stemmata 4–5, substantially closer to SO3 than to O2, O1–O2–O 3 in an acute or a right angle. The pinacula are usually well developed, but sometimes unpigmented. Prothorax with XD2– SD 1– SD 2 in a right to obtuse angle, meso- and metathorax with L2 macroscopic. Distance of D2–D2 on A1–A8 considerably longer than D1–D1, and L1 posterodorsal of L2. A1 with three SV setae. Stigma on A8 located caudal of the lines connecting D1 and SD 1 as well as SD 1 and L1. A9 with D1 near to and anterodorsally of DS1, and D2 of both sides on a single pinaculum, L2 absent. Anal plate well developed. A10: distance of II–II ≤ II–III, III a is macroscopic, distance V1–V1 smaller than on A9. The abdominal legs are fully developed, with crochets bearing two to three rows of hooks ( Hasenfuss 1960, 1963).

Food plants: larvae are mainly stem or root borers or ground-living leaf feeders of various grasses, sedges, rushes, bamboos, or mosses, rarely on other plants ( Munroe & Solis 1999, Holloway et al. 2001). The root-feeding species are most diverse in temperate zones, whereas stem-borers are more diverse in tropical and subtropical areas ( Munroe & Solis 1999). The genus Chilo has several species that are stem borers of cereal crops and sugarcane in the Africa ( Holloway et al. 2001). Crambinae larvae are common turf and sod species, and numerous species also feed on maize and other field including sugar cane and rice, where they are considered pests.

Figures

FIGURE 16. Species diversity of Indian Crambinae genera.

FIGURE 17. Species diversity of Indian Crambinae in different biogeographic zones/zones.