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The Atlantic thorny oyster can grow up to 10 centimetres (3.9 in) in diameter. The valves of the shell are roughly circular and the upper one is decorated with many spiny protuberances up to 5 centimetres (2.0 in) long. When growing in a crevice, the shape of the shell adapts itself to the available space. [4]
Spondylus shells were the driving factor of trade within the Central Andes and were used in a similar manner to gold nuggets, copper hatches, coca, salt, red pepper, and cotton cloth. [ 11 ] The use of Spondylus shells is what led to an economy of sorts in the Central Andes and led to the development of a merchant class, "mercardes", in ...
The Pectinoidea are a superfamily of marine bivalve molluscs, including the scallops and spiny oysters. [1] Shell anatomy
Spondylus varius is the largest of the spiny oysters, reaching a maximum size of about 20 cm. Aside from the size, the shell is easily recognisable because its adult part is white, but a colourful (usually crimson, but it can be yellow) prodissoconch is clearly visible at the apical end.
Called Shishania aculeata, the new fossil reveals that the most early molluscs were flat, shell-less slugs covered in a spikey armour. Half-a-billion-year-old spiny slug reveals the origins of ...
She also edited Lamprell's book, Spondylus: Spiny oyster shells of the world, in 1986. [2] Whitehead spent over 50 years collecting shells, particularly along the coast of Queensland. She found specimens in mangrove forests and on beaches, rocky outcrops and coral reefs. [3]
Thorium is a weakly radioactive light silver metal which tarnishes olive grey when it is exposed to air, forming thorium dioxide; it is moderately soft, malleable, and has a high melting point. Thorium is an electropositive actinide whose chemistry is dominated by the +4 oxidation state; it is quite reactive and can ignite in air when finely ...
The rigid shell has a pair of thick spiny valves held together by ligaments that run along the entire dorsal side of the bivalve. The bivalve is triangular with 15 to 25 low ribs radiating from the pointed anterior end (or umbo) to the large posterior edge. The exterior of the shell is usually a dull brownish color with many small tube-like ...