Meristic and Morphometric Studies of African River Prawn (Macrobrachium vollenhovenii - Herklots, 1857) from Badagry, Lagos and Epe Lagoons, South-West, Nigeria

Abstract

Macrobrachium vollenhovenii is a decapod that has been widely identified in terms of its economic importance and recruitment into aquaculture. The racial studies of M. vollenhovenii collected from Badagry, Lagos and Epe Lagoons were carried out for 12 months in order to determine the variation among the populations within the interconnected lagoons. The physico-chemical parameters of the lagoons were also determined using standard methods. The result from these physico-chemical parameters reflected environmental differences as a result of the variation in salinity from the three lagoons. Eleven characters (eight morphometric and three meristic) were studied and the results showed significant differences (P < 0.05) in the carapace length, carapace width, egg diameter, dorsal and ventral rostrum teeth with no significant differences (P > 0.05) in the total length, telson length, rostrum length, 3^rd abdominal somite, left cheliped length and the right cheliped length of M. vollenhovenii. The result gave an indication that the populations of M. vollenhovenii from the lagoons are morphologically inseparable. Though, the variations in the meristic and some of the morphometric features could be as a result of changes in salinity gradients from the three lagoons and maybe an indication of genetically distinct populations. Therefore, further work in the search for genetic diversification will require molecular characterization to detect probable variation among the populations. The study provided a concrete and important biological database useful in the species identification, nomenclature, rational exploitation and proper management of the prawn populations in the three lagoons.