Comparative Analysis Of The Morphometric And Meristic Character Of Lutjanidae From Lekki And Badagry Lagoons In Lagos State Nigeria.

Abstract

Due to identification problem that exist between fishes of different species, hence the need to compare the morphometric and meristic character of lutjanidae, L. goreensis (valenciennes 1830) and L. agennes (Blecker 1863) from Lekki lagoon and Badagry creek of Lagos State Nigeria. The lutjanids L. goreensis and L. agennes is one of the fish species that contribute to the fisheries of Lagos Lagoon. A total of 120 samples (60 from lekki and 60 from badagry) were caught from the two (2) sampling stations located in the Lagoon of Lagos State. Morphometric measurements and meristic characters were determined on the specimens to ascertain the possibility of morphological and meristic diversity among them. The morphometric measurements i.e. eye diameter (ED) for L. goreensis varied from 1.7-2.5cm, while L. agennes was 1.3-2.2cm; head length (HL) in L. goreensis was 8.8-11.2cm while L. agennes was 3.7-11.2; body depth (BD), in L. goreensis it was 10.2-17.9cm while L. agennes was 3.8-15.5cm; standard length (SL),in L.goreensis was 19-23.5 cm while that of L.agennes was11.7-23 cm and total length (TL), in L.goreenis was 28.5-35cm while that of L.agennes was 14.2-35cm. The meristic characters of the species included 10 dorsal spines for L.goreensis, 14 rays in the posterior dorsal fin; 3 was also recorded for the anal spine and 8 rays in the posterior anal fin, same value were also obtain in L. agennes except for a little difference in the number of scales with L.goreensis having 36-60 and L. agennes showing 36-58. The populations of the species from the two (2) sampling stations in the lagoon showed variations in morphometric measurements and similarities in meristic counts but these did not differ significantly (P>0.05) indicating that species from the stations may not be genetically diversed. These insignificant variations may be related to the geographical ecological activities of the lagoon. In the present study there was no taxonomic variation among the two species of fish L. goreensis and L. agennes in Lagos Lagoon based on the stated methodology. In furtherance of this work, a research programme must be embarked upon at molecular level of analysis (e.g. Randomly Amplified Polymorphic DNA (RAPD) primers, RAPD markers) which may provide better or more precise results on genetic and morphological diversities among the species of this fishes in Lagos Lagoon, Nigeria.