Tag: Shell Club

Tectus triserialis, Lamarck, 1822. Caught in 50 meters deep rocky & muddy bottom, Semirara Islands, Samar, Philippines.

Tectus conus, Gmelin, 1791. On rock and rubble, collected by local fishermen by nets near Rapu Rapu Island, Albay Gulf,  Philippines.

Trochus ferreirai, Bozzetti, 1996. Trawled in 50 meters depth, Masbate, Philippines.

Monodonta labio, Linné 1758. Rocky shore in shallow water, Negros Island, Philippines.

The Trochidae are conical shaped gastropods. They are herbivorous and found grazing on seaweed and algae covered rocks. Trochidae are found worldwide in tropical waters and well represented in the Philippines where all of our specimens were collected. These four specimens exhibit the diversity of the family in shape and size, although many come much much smaller and one, Tectus niloticus. grows so large that it dwarfs the largest of these. It is interesting that this family favors reds and greens, two colors not often found in other gastropods. These shells are pearlescent under the outer layer. This inner layer is called “nacre” or mother of pearl in plain English.  “Pearlized” specimens of the larger specie are found in the tourist shops. Trochus ferreirai was discovered less than twenty years ago and until very recently sold for over $20 each. Its red and white swirls make it very attractive Specimens of the upside down ice cream cone shaped Tectus triserialis, while not rare, are difficult to acquire. Tectus conus is the most popular of the lot, rightfully so due its large size, elegant shape and beautiful coloration.

Shells donated by Richard Kent

When B.C. Burgess wrote his monumental book “The Living Cowries” in 1970 little was known about the South African endemic cowries. In fact according to Burgess there existed no live collected specimens of either Cypraea fuscorobra or Cypraea edentula. In the years that have passed, SCUBA has become much more prevalent and live specimens of all the South Africans are available. Still they are anything but plentiful on the market. At the Cape of Good Hope the Atlantic and the Indian Oceans converge. All the major mollusc families have members indigenous to the area. Cypraea fuscorobra and Cypraea edentula are members of the genus Cypraeaovula, Gray 1824. Both belong to the “algoensis” group. Cypraeaovula are noted for ecological variations and hybridization. Some are quite difficult to identify, even with a guide book. Cypraea edentula, Gray 1825 lacks teeth and is called, as to be expected, the Toothless Cowrie. It is commonly between 18 and 24 millimeters in size. Small specimens are more available than large ones. Cypraea fuscorobra, Shaw 1909, has the boring common name of “Reddish Brown Cowrie.” It is rather globular in shape with a large callous and larger in size, the average being between 30-36 millimeters. Both retail in the $15 to $25 range. Choice specimens, especially of Cypraea edentula are hard to find. Both are prone to stress marks across the dorsums. Our two specimens both collected this year are donated by Richard Kent. They were acquired direct from a South African dealer, are of superior quality and fine starters for a South African collection. Many of the closely related and similar looking species are considerably more expensive and very difficult to acquire without a direct South African source.

Cypraea fuscorubra, Shaw 1910, Scuba on reef at 36-40m, Hout Bay, South Africa 2012

Cypraea edentula, Gray 1822, Scuba at 15m on reef, Port Elizabeth, South Africa 2012

It sure is a mouthful to pronounce the name! Pterynotus miyokoae is one of the most spectacular of the murex with elegant “wings” and marvelous delicate sculpturing. Scholars debate how it ended up a Pterynotus, with some saying it should be a Chicoreus. Other Pterynotus shells are awkward in appearance, misproportioned with their wings irregularly developed. Miyokoae are brown banded while Pterynotus are solid white or pastels. Pterynotus are very variable whereas the miyokoae are amazingly consistent. This was a very expensive shell when Kosuge described it in 1979 but prices have greatly declined. As all miyokoae look exactly the same, the lack of variety has reduced the value. It is indigenous to the Philippines where recently albino populations have been discovered.