The Phuket and Similan Islands Trip (Thailand)

An older, reliable record of the local cowry fauna of forty years ago was Assembled by Ludwig Gabrielli, who collected in the depth between 1 and 3 meters, from the beach of Rawai as far as the southern tip at Cape Pronthep to Nai Harn Beach.  He recorded 22 species of cowries that were "abundant" as living specimens, and another 10, which he found in small quantities.

 

Judging from the material the compressor divers operating between 2 and 10 meters brought up during a week's diving, only E. caurica is still abundant in the area, plus five other species not on our search-list. We did not see any globulus, dead or alive, and may assume that this formerly abundant species has disappeared from the area.  It belongs to the genus Pustularia, which is usually found in clean, turbid water, in association with sponges and coral reefs. Gabrielli reported finding it in small groups among small colonies of Acropora corals.  The same is true for Blasicrura interrupta, a formerly abundant species in the vicinity of Phuket, judging from the amount of shells in collections.  

 

Not a single specimen was found by neither us or the compressor divers.  These experienced fishermen spend up to 5 hours at a time in the muddy waters, connected to a compressor with a garden hose. They managed to find a single living specimen of B. ursellus, whose DNA was analyzed by Dr. Christopher Meyer of the Smithsonian Institute, Washington. The data corresponds with that derived from a specimen collected off Phuket many years ago and confirms the Thai population of ursellus to represent a new subspecies (u. jomi). The same outcome was achieved from analyzing specimens of caurica (chrismeyeri), punctata (conleyi) and ziczac (yzac), all of which have been named in 2017. Apparently, the region around Phuket has a unique fauna of Cowries whose shells resemble those of their Indian Ocean relatives, while their molecules reveal a long history of reproductive separation.

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