Biogeographic distribution of the cyclopoid copepod genus Oithona – from mesoscales to global scales

• Distribution and abundance patterns of Oithona spp. vary locally and worldwide
• A remarkable horizontal variation and abundance patterns of Oithona spp.
• Wrong presence and abundance estimates are due to large mesh sizes

Abundance and productivity of smaller copepods such as the cyclopoid Oithona spp. have been substantially underestimated in most studies, primarily due to large mesh sizes employed during zooplankton tows. Several studies demonstrate that the assemblage structure of Oithona spp. shows considerable variation at temporal and spatial scales. We report here the remarkable horizontal variation in distribution as well as abundance patterns of 8 Oithona species off northeastern Taiwan in the southeastern East China Sea and compare this distribution pattern with community compositions worldwide. The present study provided the first explanation of a spatial distribution pattern and a relationship between species richness and area, as well as community similarities with increasing distance worldwide for the ecologically important planktonic copepod genus Oithona.