Guildfordia Yoka Shell
Guildfordia yoka, the yoka star turban, are deep-water sea snails, marine gastropod mollusks, in the family Turbinidae, the turban snails.
These tropical marine species are found in the Western Pacific off Japan and the Philippines, living at depths between 660 to 1,640 feet.
The Guildfordia Yoka grows to an average of 2 1/2 to 4 inches. The color pattern of the shell ranges from very light brownish to purple-brown. Some specimens contain only 6 whorls instead of 7 as in the holotype. The upper whorls are smooth, then follows the body whorl with 2 rows of granules, instead of 7 or 8. The Guildfordia Yoka keel has irregular radiating ribs, which leave a nearly smooth zone above the keel, with only a few spiral striae.
The base of the shell is less convex than the upper part. Some specimens lack the rose-colored line around the umbilical callosity. The aperture is oval & thick, with the nucleus in the external lower corner. The outer surface is rugose, by irregular wrinkles, nearly parallel with the basal margin of the operculum. The nucleus is marked by an olive spot.
Embryos of Guildfordia Yoka develop into free-swimming planktonic larvae with several bands of cilia (trochophore). Later they develop into juvenile veligers, finally into fully grown adults.
(REF G.W. Tryon (1888), Manual of Conchology X; Academy of Natural Sciences, Philadelphia) (REF: Beu, A. G. (1970). Descriptions of new species and notes on taxonomy of New Zealand Mollusca. Transactions of the Royal Society of New Zealand, Earth Science.)
Scientific classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
Subclass: Vetigastropoda
Order: Trochida
Super family: Trochoidea
Family: Turbinidae
Genus: Guildfordia
Gray, 1850
Type species: Trochus triumphans
Philippi, 1841
GY-17
One Guildfordia Yoka shell, measuring 2 3/4 to 3 inches....... $2.49