Resolution of the Aetomylaeus nichofii species complex, with the description of a new eagle ray species from the northwest Indian Ocean and a key to the genus Aetomylaeus (Myliobatiformes: Myliobatidae)

In recent years, the eagle ray family Myliobatidae has undergone major taxonomic revisions due to molecular and morphological findings. A new species of eagle ray, Aetomylaeus wafickii sp. nov., is described based on specimens collected from the Arabian Gulf, Northwest Indian Ocean. The new species externally most closely resembles A. caeruleofasciatus White, Last, & Baje, 2015 in White et al. 2016 and A. nichofii (Bloch & Schneider, 1801 ). It can be distinguished from these species by a combination of morphological and meristic characteristics including a higher number of transverse pale bluish to light grey bands on its dorsal surface (8–10 in Aetomylaeus wafickii sp. nov. vs 5–8 in A. caeruleofasciatus and A. nichofii ), a higher number of tooth plate rows (13–15 vs 7), a shorter upper tooth plate width (3.1–4.3 vs 4.6–7.5%DW), and a shorter tail ((0.9–1.6) vs (1.4–1.8)) times disc width. Pelvic fin radial counts separate the new species from A. nichofii for males (14–16 vs 16–19) and females (16–19 vs 20–21). Geographically, it occurs from the southern Red Sea, eastwards to the Arabian Sea, and south to Sri Lanka, including in the Arabian Gulf. It appears to be frequently caught as bycatch in gillnets due to its habit of schooling, and is considered particularly susceptible to impacts from regional fisheries. Morphological and meristic findings complement prior molecular evidence documenting three species within the A. nichofii complex. A key to the genus Aetomylaeus is provided for the first time.