Biometric relationships and condition factor of Tetralia glaberrima Herbst, 1790, Gulf of Aqaba, Red Sea, Egypt

Abstract

The biometric relationships of the Tetralia glaberrima individuals collected from hermatypic branched coral colonies at Gulf of Aqaba were treated during this study. These results showed that the relationship between carapace length (CL) and total body weight (W) for the whole population (sex combined) is highly correlated with the formula Log W= - 0.42 + 3.32 Log CL, while carapace width-weight relationship for whole population was Log W= - 0.62 + 3.4 Log CW. No significant difference between sexes, these relations are curve linear and has positive high correlation coefficient ‘r’ being 0.87 and 0.94 respectively. The regression coefficient ‘b’ is 3.32 and 3.4 with an intercept of Y- axis ‘a’= - 0.42, -0.62 respectively, showing an allometric positive correlation coefficients which denotes to the faster increase in body weight than in carapace length. On contrast, the relationship between carapace length (CL) and carapace width (CW) for sex combined was isometric with regression coefficient (b= 1.0557). The relative condition factor ‘Kn’ varied from 0.758 in immatures and juveniles, increased to 1.180, with an average of 0.991±0.102 in adults. The average value for “kn” was ideally and very close to 1, indicating good well- being allover the year round.