COMPARATIVE MORPHOMETRIC AND MERSTIC STUDY ON YELLOW FIN SEABREAM, ACANTHOPAGRUS LATUS IN IRAQI WATERS

Abstract

Yellow fin seabream Acanthopagrus latus (Houttuyu, 1782) collected from Shatt al-Arab river, Shatt al-Basrah Canal and Iraqi marine water, North West Arabian Gulf were classified depending on the morphometric and merstic characters. Samples were obtained from December 2006 to October 2007. Twenty two morphometric characters and twelve characters for the species were described. The morphometric characters were calculated as numerical ratio to standard and head lengths and the relationships between the standard length and other morphometric characters were calculated. The indices characters associated with standard length varied from 0.79 of fork length in Shatt al-Arab to 17.54 of snout length in Iraqi marine water. While indices of characters associated head length ranged from 0.93 of head depth in Shatt Al-Arab to 5.95 of snout length in marine water. The slopes of the regression line between the standard length and the morphometric measurements ranged from 0.026 of eye diameter in marine water to 1.084 of total length in Shatt Al-Arab. The lowest values of correlation coefficient were observed between the standard length and eye diameter (0.75) and between the head length and eye diameter 0.83 in Shatt Al-Arab. No significant variations in merstic characters of fish between the three regions. The low values of the coefficient of variation (CV%) for characters (<10) may indicate little influence of environmental variation on morphometric variability. The morphometric and merstic characters showed that the A. latus in Shatt Al-Arab river, Shatt Al-Basrah Canal and Iraqi marine water considered as one group no more.