Record of <i>Oreochromis aureus</i> (Steindachner, 1864) (Teleostei: Perciformes: Cichlidae) in the natural waters of Tamil Nadu, India

Of the many fish introduced globally for aquaculture, Tilapia can be considered as the most widely introduced species. The Mozambique Tilapia, Oreochromis mossambicus Peters, 1852, was the first species to be widely introduced for aquaculture. FAO Database on Introductions of Aquatic Species (DIAS; FAO, 2000-2009) states that O. mossambicus was first introduced to India during the year 1952 (Devadas & Chako, 1953) from Sri Lanka and Thailand for aquaculture with the idea of reservoir fisheries. O. niloticus Linnaeus, 1758, was introduced to India as late as 1990 from Thailand. O. mossambicus has found its way into the list of 100 of the World’s worst Invasive Alien Species published by Invasive Species Specialist Group (ISSG) (Lowe et al., 2000). It has established itself in the wild which may be attributed to intentional release or escapes from fish farms. widely spread throughout Asia and occur in natural and quasi-natural waters. This has caused increased concern among conservationists and environmentalists (Pethiyagoda, 1994). A similar species, Oreochromis aureus (Steindachner, 1864), commonly called the Blue Tilapia which is a native of Africa and Middle East has also been introduced for commercial fisheries. Though there is no official record of blue tilapia being introduced into India, specimens of O. aureus (fig. 2A, B & C) were collected by the senior author from water bodies in and around Pallikaranai marsh in Chennai, Tamil Nadu, India. These fishes could have been brought in accidentally along with O. mossambicus fingerlings for aquaculture. The meristic details of ten specimens of O. aureus collected from Chennai are as follows: D.17/12-13; P.1/12-13; V.1/5; A.3/9-11; C.16; Lateral row of scales: 30-33; L.l. pored scales in upper and lower rows: 20-23/14-18 and gill rakers in the first arch: 21-23/5-7. The TAPROBANICA, ISSN 1800-427X. October, 2009. Vol. 01, No. 02: pp. 126-129. © Taprobanica Nature Conservation Society, 146, Kendalanda, Homagama, Sri Lanka.