Tamba cosmoloma Prout, 1928: 468 (Figs 8, 22–23) Type locality: Mt. Poi, Sarawak (Borneo, Malaysia) Material examined: India, Andaman and Nicobar Islands, Great Nicobar Island: 2 ♂, Steel Bridge, East West Road, 13.xi.2018 (NZCZSI, 9283/H10); 1 ♂, Bird Watching Point, 14.xi.2018 (NZCZSI, 9284/H10); 1♂, Afrabay, 14.xi.2018 (NZCZSI, 9285/H10), K.C. Gopi & party leg. Diagnosis: Forewing length: ♂ 17–18 mm. T. cosmoloma has characteristic pale reddish-brown, obliquely sinuous, transverse fasciae on fawn ground colour of both the wings. Double post-median fascia of both the wings is little more prominent than the rest of the fasciae and beyond which faint reddish-brown shading, restricted within the anterior half of the marginal area of only forewing. Each wing with a sub-tornal black spot, that on hindwing is larger. Male genitalia have typical triangular valva with short costa and long, straight and broad sacculus, a thumb like distal costal process, asymmetrically bilobed distal saccular process and elongated, distally setose, tongue-like juxta. Distribution: Indonesia (Java, Sulawesi, Sumatra), Malaysia (Borneo and Malay Peninsula), Thailand (Holloway 2005), India (the Great Nicobar) (present study). Remarks: Based on reddish-brown shading of both wings, T. cosmoloma exists in two distinct forms. The form studied herein has faint shading restricted within the anterior half of the marginal area of forewing, whereas, the other form has more intense, dark reddish-brown shading on both the wings. T. cosmoloma is infrequent, but generally found in lowland, tropical rainforests and in both pristine and disturbed habitats (Holloway 2005). The present records of this and the next species add two more members to the existing 10 species of Tamba in India.

Published as part of Singh, Navneet, Ahmad, Jalil & Raha, Angshuman, 2022, Contribution to the Erebidae fauna of the Great Nicobar Island, India with description of two new species (Lepidoptera: Noctuoidea), pp. 79-94 in Zootaxa 5165 (1) on pages 86-87, DOI: 10.11646/zootaxa.5165.1.3, http://zenodo.org/record/6825519