Marine biologists have described a new species of the oyster genus Pinctada from the east coast of Phuket Island, Thailand, in the Andaman Sea.
Shell of Pinctada phuketensis from Dok Mai Island, Phuket, Thailand; external and internal views of left and right valves: (A and C) paratypes; (B) holotype. Abbreviations: LV – left valve; RV – right valve. Scale bars – 5 cm in (A), 4 cm in (C). Image credit: Somrup et al., doi: 10.3897/zookeys.1119.87724.
Pinctada is a genus of saltwater oysters in the bivalve mollusk family Pteriidae.
There are approximately 20 scientifically recognized Pinctada species.
They are widely distributed from shallow to deep waters of the tropical and subtropical regions between the Indo-Pacific and western Atlantic.
They are not closely related to either the edible oysters or the freshwater pearl mussels.
Several Pinctada species produce the pearls of jewelry quality that seem to have sustained from ancient times the human definition of beauty and rarity.
“Several Pinctada species are used widely in pearl aquaculture and in industry including the Akoya pearl oyster (Pinctada fucata) in Japan; the black-lip pearl oyster (Pinctada margaritifera) in the South Pacific and Indo-Pacific Islands; and the silver-lipped pearl oyster (Pinctada maxima) in western Australia,” said Kasetsart University researcher Narongrit Muangmai and colleagues.
“While the pearl farming industry has expanded rapidly during recent decades, our understanding of biodiversity, evolution, and conservation of Pinctada species is still limited.”
In their new study, the scientists examined 15 specimens of pearl oysters collected around Dok Mai Island by SCUBA diving.
“We recently collected several Pinctada specimens from Phuket, and some of them were quite different in external appearance from other reported Pinctada species in this area,” they said.
“In the present study, we aimed to clarify the taxonomic status of these specimens based on morphological and molecular analyses.”
Their analyses and species delimitation approach showed that the specimens were genetically distinct from other species in the genus.
Named Pinctada phuketensis, the new species resembles the Akoya pearl oyster but differs by its smaller size (shell height does not exceed 8 cm, or 3.1 inches) and the absence of hinge teeth.
“The new species can be distinguished from other members of the genus by its smaller size, a subquadrate shell with moderately long ligament, slightly developed to undeveloped posterior auricle, the absence of hinge teeth, a pale to transparent non-nacreous margin with dark brown or black blotches, and brownish stripes on the external surface,” the authors said.
“It is apparent that further work on Pinctada species based on combined data of different genetic markers and more expansive sampling from different geographic regions will uncover their diversity, phylogenetic relationships and evolutionary patterns,” they added.
The team’s paper was published in the journal Zootaxa.
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S. Somrup et al. 2022. Pinctada phuketensis sp. nov. (Bivalvia, Ostreida, Margaritidae), a new pearl oyster species from Phuket, western coast of Thailand. ZooKeys 1119: 181-195; doi: 10.3897/zookeys.1119.87724
Source link: https://www.sci.news/biology/pinctada-phuketensis-11165.html
