Biological and morphological aspects of spiny eel Mastacembelus mastacembelus (Banks and Solander, 1794) inhabiting Al-Tharthar canal / Samarra, Iraq

Abstract

Biological aspects (size composition, length-weight relationship, condition factor, food habit and reproduction season), and morphological of Mastacembelus mastacembelus inhabiting Al-Tharthar canal studied during the period from April to September 2012. The growth pattern was negative allometric with (b) values for males 2.680, females 2.845 and for combined sexes 2.597. Condition factor values were lower than one, ranged from 0.183 to 0.432 with average 0.282 ±0.053 for combined sexes. Food items from stomach collected and analyzed using both points and frequency methods. Two food items found only in the diet. M. mastacembelus is a predator, the males preferring fish while the females preferring fish and crustacean (prawns). The research cover, the ratios each of sixteen morphometric measurements to standard length, and each of four morphometric measurements to head length and their linear regression equations. All the length-length relationships between standard length and the others measurements were highly correlated except head depth, body depth and body width, and for head length, head depth only.