Correlation between Morphometric and Dimorphic Variables to Characterize Potamon ebonyicum (Crustacea: Decapoda: Brachyura) from Ebonyi River Basin of Nigeria
Rupert C. Akpaniteaku *
Department of Biological Science, Evangel University Akaeze, P.M.B. 129, Abakaliki, Ebonyi State, Nigeria
John N. Ofoma
Unit of Mathematics, Department of Physical Science, Evangel University Akaeze, P.M.B. 129, Abakaliki, Ebonyi State, Nigeria
Richard C. Ogbonna
Unit of Mathematics, Department of Physical Science, Evangel University Akaeze, P.M.B. 129, Abakaliki, Ebonyi State, Nigeria
*Author to whom correspondence should be addressed.
Abstract
Studies were carried out to determine relationships between morphometric and dimorphic variables of freshwater crab, Potamon ebonyicum. Parameter measurements were taken from side to side (left and right); and from tip to the extremity of characteristic features, to ensure that values were obtained at the widest points. The dimorphic variables showed positive correlation and linear relationship between male and female. Nonlinear relationship was recorded in most variables morphologically. Regression analyses revealed poor correlation between carapace length (CL) and weight, and between carapace width (CW) and weight. There was a positive correlation between CL and CW of both sexes. The findings could be a guide for determining condition factor. They could also be useful in field identification and further classification of freshwater crab.
Keywords: Relationship, characteristic variables, freshwater crab, Potamon ebonyicum, South East Nigeria