Thalerosphyrus Eaton 1881

Larval key to the genus Thalerosphyrus from India 1. Posterolateral expansions of abdominal segments well developed on III–VIII and directed outwards (Figs 97–98); pronotum greatly enlarged laterally and posteriorly (Fig. 96); anterior margin of the labrum with a smooth, shallow depression in the middle area (Fig. 99)........................................................................... T. flowersi - Posterolateral expansions of abdominal segment III–VIII moderately developed (Figs 4–5, 53–54); pronotum is moderately enlarged laterally and posteriorly (Figs 4–5, 51); labrum a different shape......................................... 2 2. Posterior margins of terga with irregular pointed teeth and a row of microdenticles (Figs 84–86); hind tibia with two rows of thin setae on the dorsal face of hind femora arrow-shaped......................................................3 - Posterior margin of tergites with regular pointed teeth, and numerous microdenticles (Selvakumar et al. 2017: Fig. 21); hind tibia with one row of thin setae; setae on the dorsal surface of hind femora truncate or rounded at apex (Selvakumar et al. 2017: Fig. 15)............................................................................... T. meghalayensis 3. Hind femur dorsal surface with arrow-shaped, blunt and strong setae (Fig. 40); labrum expanded laterally, 4.5× wider than long, anterior margin straight, medially bulged with a concave shape and small blunt crenations on either side, (Fig. 12)........................................................................................... T. bengalensis sp. nov. - Hind femur dorsal surface with arrow-shaped setae, clearly point (Fig. 75); Labrum moderately broad, 3.5× wider than long, anterior margin straight (Figs 57–58)....................................................... T. sartorii sp. nov.