
%0 Journal Article
%A Mukai, H 
%T Biogeography of the tropical seagrasses in the western Pacific
%J Marine and Freshwater Research
%D 1993/02/01
%V 44
%N 1
%P 1-17
%K 
%R https://doi.org/10.1071/MF9930001
%U https://www.publish.csiro.au/paper/MF9930001 
%X Seagrass species and their distributions were recorded from 18 localities in the tropical  and subtropical Pacific. These field observations were collated with a review of the  recent literature, enabling the present distribution patterns of seagrass species in the western  Pacific to be described and the origin of those species to be discussed in relation to the major  oceanic currents of the region. The major tropical seagrasses of the western Pacific are  Thalassia hemprichii, Enhalus acoroides, Cymodocea rotundata, C. serrulata, Halodule uninervis,  Syringodium isoetifolium and Thalassodendron ciliatum, with T. hemprichii and E. acoroides  being the two most widely distributed species. Species are found in coastal waters along the  Equatorial Countercurrent and the Kuroshio and East Australian Currents. The highest number  of seagrass species occurs in the coastal waters of Malesia enclosed by Indonesia, Borneo,  Papua New Guinea and the Torres Strait (northern Australia). This area is considered to be  the source of all of the seagrass species of the western Pacific, i.e. the centre of their origin.  A relationship between the distance from this centre of origin along the above three major ocean  currents and the diversity of seagrass species was found: the further from the origin, the poorer  the seagrass diversity. These observations support the centre-of-origin theory that was first  proposed by den Hartog to describe the processes responsible for the present distribution  patterns of seagrasses in the western Pacific. 
