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Biogeography of marine podocopid ostracodes in Micronesia

January 1, 1989

Bottom lagoonal sediment samples from 12 islands and atolls yielded >70 species representing >32 ostracode genera. All or most samples from a particular lagoon generally form distinct subgroups (Jaccard =0.45-0.50). At lower levels, 5 groups delineate faunal regions within Micronesia: the Gilbert Islands (Onotoa) in the SE part of the region, the N Marshall Islands (Enewetak, Rongelap, Bikini), the SE Marshall Islands (Kwajalein, Jaluit, Majuro, Arno), the Marianas and Caroline Islands (Guam, Truk, Pohnpei) and Pingelap. Pingelap, Kwajalein and Onotoa have the highest species richness (S=32-42) and Shannon-Wiener diversity values (H(S)=2.62-3.02) in the study area. Enewetak, Jaluit, Majuro and Arno show lower values (S=23-27, H(S)=2.29-2.70). Of the ostracode species living in Micronesia, 64.3% have Indo-West Pacific affinities, 7.1% are circumtropical, 5.7% have East Pacific-Caribbean affinities, 11.4% are endemic to Micronesia, and 11.4% have unknown affinities. If the SE Asian region is a primary species-source, results show that each Micronesian lagoon is equally likely to be colonized by dispersal from the source region, despite differences in distance from a hypothetical source. However, each lagoon has a distinct ostracode assemblage, probably the result of unique history of random colonization events, local extinctions and environmental disturbances. -from Authors

Citation Information

Publication Year 1989
Title Biogeography of marine podocopid ostracodes in Micronesia
Authors L.S. Weissleader, N.L. Gilinsky, R.M. Ross, T. M. Cronin
Publication Type Article
Publication Subtype Journal Article
Series Title Journal of Biogeography
Index ID 70015991
Record Source USGS Publications Warehouse