Abstract:
Thadsin Panithanarak, Ratima Karuwancharoen, Uthairat Na-Nakorn, and Thuy Thi Thu Nguyen (2010)
Population genetics of the spotted seahorse (Hippocampus kuda) in Thai waters: implications for conservation.
Zoological Studies 49(4): 564-576. A population genetics approach was used to investigate the genetic diversity
of the spotted seahorse (Hippocampus kuda) in Thai waters; specifically, the degree of genetic differentiation
and species evolution was inferred from sequence analysis of 353 bp of the mitochondrial (mt)DNA control
region. The data were then used to identify discrete populations in Thai waters for effective conservation
and management. Spotted seahorses were collected from 4 regions on the east and west coasts of the
Gulf of Thailand and a geographically separated region in the Andaman Sea. Of the 101 mtDNA sequences
analyzed, 7 haplotypes were identified, 5 of which were shared among individuals from the east and west
coasts of the Gulf of Thailand. The remaining haplotypes were restricted to individuals from the Andaman Sea.
Nucleotide and haplotype diversities were similar within the Gulf of Thailand samples, whereas diversity was
lower in the Andaman Sea sample. Genetic differentiation appeared between pairs of samples from the Gulf
of Thailand and Andaman Sea (FST, p < 0.0001). A large genetic variance appeared among the 2 population
groups (94.46%, ΦCT = 0.94464, p < 0.01). A Neighbor-joining tree indicated that individuals from the Gulf of
Thailand and Andaman Sea formed 2 phylogenetically distinct groups, which were segregated into different
population-based clades. While results reported here indicate that populations from the Gulf of Thailand and
Andaman Sea should be treated as separate conservation units, a larger sample size from the Andaman
Sea is required to confirm this genetic partitioning and low level of diversity observed in the present study.