Dynamics of Odontella spp. in the Atlantic Ocean of Nigeri

Abstract

Odontella is a planktonic centric diatom widely distributed in saline waters. Although some studies on marine phytoplankton in Nigeria mention the genus, there is a considerable dearth of information on its distribution in the Atlantic Ocean (Nigeria). This paper examined the density, diversity, spatial and temporal distribution of Odontella species in the Atlantic Ocean, in the Bight of Benin and Bight of Bonny (Nigeria). Phytoplankton samples were collected from 10 locations on the stretch of the Atlantic Ocean (Nigeria), in four seasons (dry-wet, wet, wet-dry and dry). Results revealed that eight species of Odontella, namely O. aurita, O. granulata, O. longicruris, O. mobilensis, O. obtusa, O. regia, O. rhombus and O. sinensis occurred in the Atlantic Ocean (Nigeria). The eight Odontella species showed differential distributional pattern, both spatially and temporally. Akwa Ibom location had the highest Odontella abundance in the South-South region while Ondo was highest in the South-West region. Higher Odontella abundance was recorded in the transition seasons (dry-wet and wet-dry seasons) than in the typically wet and dry seasons. The species O. regia was dominant and widely distributed in the South-West region, while O. aurita was dominant in the South-South region. Relatively, the density of O. longicruris was low throughout the Atlantic Ocean (Nigeria) and at all seasons. O. regia and O. sinensis were the most widely distributed species in the Atlantic Ocean (Nigeria) and occurred all through the seasons studied while O. obtusa occurred sparingly throughout all the seasons.