Genetic and morphological differentiation in the Sakura shrimp (Sergia lucens) between Japanese and Taiwanese populations

Abstract

The Sakura shrimp Sergia lucens is a remarkable meso-pelagic crustacean species, which is harvested for human consumption in restricted geographical areas of Taiwan and Japan in the northwestern Pacific. Nucleotide sequence analysis of the mitochondrial DNA control region was conducted to investigate the levels of genetic variability and differentiation between Japanese and Taiwanese populations of S. lucens. The latter half of the control region, which contained 589 nucleotide sites, was sequenced using DNA extracted from 178 individuals from the two geographical regions. Analyses yielded 162 haplotypes, and the amount of genetic variability within the populations as shown by the levels of haplotype and nucleotide diversity revealed that the two populations included in this study have higher levels of diversity than intraspecific variation previously reported in other crustaceans. Our AMOVA and pairwise Fst results indicated the existence of significant genetic differences between the Japanese and Taiwanese populations. Morphological analyses also revealed minor but notable differences between the two groups. These findings suggest that postulated gene flow of S. lucens is unlikely to occur across the isolated Japanese and Taiwanese populations, and that each population completes their life history in a restricted geographical area.

Genetic Isolation among the Northwestern, Southwestern and Central-Eastern Indian Ocean Populations of the Pronghorn Spiny Lobster Panulirus penicillatus

“…The values generated in this study are comparable with those derived from the mtDNA control region sequences for the crustaceans Farfantepenaeus aztecus , Litopenaeus setiferus and Sergia lucens [16,17]. Haplotype diversity ( h ) within the geographical populations was high, ranging from 0.9986 in Nilandhoo atoll, Maldives to 1.0000 in Fort Dauphin, Madagascar.…”

New record of <i>Lucensosergia lucens</i> (Hansen, 1922) in the waters off Nagasaki, western Japan

“…Besides Suruga Bay, it is distributed in the neighboring waters of Sagami Bay and Tokyo Bay (Omori 1969). The same shrimp has been found and is being fished commercially off Tung-kang and around Gueishan Island, Taiwan (Omori et al 1988, Lee et al 1996, Imai et al 2013. These locations in Japan and Taiwan have the similar characteristic that water from large rivers discharges into a deep submarine canyon adjacent to a river mouth.…”

“…These locations in Japan and Taiwan have the similar characteristic that water from large rivers discharges into a deep submarine canyon adjacent to a river mouth. Imai et al (2013) indicated that the populations of Suruga Bay and off Taiwan are isolated breeding units due to a lack of observed ongoing gene flow. The distribution of L. lucens is similar to the organisms that comprise the East Asiatic endemic population (Nishimura 1981).…”

Extreme mitochondrial variation in the Atlantic gall crab Opecarcinus hypostegus (Decapoda: Cryptochiridae) reveals adaptive genetic divergence over Agaricia coral hosts

“…This result was confirmed by the ABGD analysis. Extreme levels of genetic variation have been reported within natural populations in, for example, planktonic chaetognaths (arrow worms)40 and mesopelagic shrimp41. Many instances of high mitochondrial diversity have directly or indirectly been interpreted as evidence of cryptic speciation, but some of these cases may need to be subjected to re-evaluation when investigated using nuclear loci4042.…”