Ixa cylindrus

Ixa cylindrus (Fabricius, 1777) Ixa cylindrus — Shen 1940a: 216; Hill 1982: 201, pl. 4A. Taxonomy: Holthuis and Gottlieb (1956), Chen and Sun (2002), Takeda and Nagai (2009). Type: Syntypes in NHMD (Zimsen 1964). Type locality: Tharangambadi (= Tranquebar), India. Distribution: Western Indian Ocean to West Pacific: from East Africa, India, Singapore, Thailand, South China Sea, Taiwan, and Australia (Chen and Sun 2002; Davie 2002). Habitat: Subtidal; substrates of fine sand, muddy sand or soft mud; depths 19 to 33 m (Chen and Sun 2002). Ixa edwardsii Lucas, 1858 # Ixa cf. inermis — Hill 1982: 201, pl. 4B [not I. inermis Leach, 1817]. Ixa edwardsii — Wong et al. 2021: 19, fig. 29, pl. 6B. Taxonomy: Holthuis and Gottlieb (1956), Chen (1989), CGS Tan (1996), Chen and Sun (2002), Takeda and Nagai (2009). Type: Status unknown. Type locality: Unknown. Distribution: Western Indian Ocean to South China Sea: from East Africa, Red Sea, Persian/Arabian Gulf, India, to South China, Taiwan, Philippines and Indonesia (Holthuis and Gottlieb 1956; Chen and Sun 2002). Habitat: Subtidal; substrates of muddy-sand, sandy-mud or soft mud; depths 16 to 76 m (Chen and Sun 2002).