Sibling species in the mangrove genus Ceriops (Rhizophoraceae), detected using biochemical genetics*

Abstract

Starch gel electrophoresis of enzymes from the mangrove trees Ceriops tagal (Perr.) C. B. Robinson var. tagal, Ceriops tagal (Perr.) C. B. Robinson var. australis C. T. White, and Ceriops decandra (Griff.) Ding Hou in northern Queensland, Australia, revealed a uniform genetic structure within taxa, but high levels of genetic divergence among taxa. No more than 20% of enzyme phenotypic characters were shared by any pair of the taxa, and patterns of enzyme phenotypic variation consistent with hybridisation among them were not seen in any samples, including those from areas of spmpatry. This evidence of reproductive isolation is considered sufficient to accord species status to C. tagal var. australis.

* Aust. lnst. Marine Sci. Contrib. No. 453.