Diversity and distribution of the cladocerans (Crustacea, Branchiopoda) in Thailand.

An updated checklist of the cladoceran fauna from inland aquatic habitats in Thailand (a high-diversity hotspot in Southeast Asia), based on published cladoceran records found in literature is presented. The checklist updates nomenclature and species distributions, especially habitat preferences. A total of 138 valid recorded species is relatively high. However, the estimators indicate that more species are expected to be found with more research. The north-eastern and southern regions of Thailand are well-studied regions of high species richness with 100 and 96 cladoceran species, respectively, whereas the northern and eastern regions have large research gaps that should be studied further. Moreover, each habitat type seems to have a unique cladoceran community as the similarity values amongst them are mostly low (Sorensen similarity index < 0.50). Therefore, it is suggested that habitats with unique characteristics, such as peat swamps, stream and cave pools, are worthy of further exploration. If the current records of cladoceran diversity in Thailand confirms a high diversity of this animal in the tropical region, then the geographical distribution of each species can be properly explained.