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Bivalve of the Day |
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Smith’s Tiny Condyl Clam
Carditopsis smithii (Dall, 1896)
Family Condylocardiidae (Condyl Clams)
The prodissoconch or larval shell (artificially colored green in this scanning electron micrograph) of diminutive Carditopsis smithi is relatively large and bordered by a strong ridge. Very little is understood about the anatomy of condylocardiids. The family is very young paleontologically, known only since the Tertiary, and is represented by at least 21 living genera and at least 65 species, distributed worldwide but mainly in the antiboreal regions. Some features of condylocardiids (such as an adult byssus, brooding larvae, absence of the outer demibranch of the gill) suggest that their evolution involves pedomorphosis, or the retention of larval characters in the reproductive adult.
Evolution on the Half Shell...
The Assembling the Tree of Life: Bivalvia project (BivAToL) is a part of the Assembling the Tree of Life initiative, a large research effort sponsored by the National Science Foundation. Its goal is to reconstruct the evolutionary origins of all living things.
Jetsam & Flotsam
Not only do bivalves vary greatly in size and shape, but they also look different inside. Below is the internal anatomy of 2 species of clams.
[+]In July 2011 at the 77th Annual Meeting of the American Malacological Society, Ilya Temkin presented a paper in the “Cretaceous and Cenozoic Molluscan Paleontology Symposium,” coauthored with Ellen Strong, entitled “Evolution of the alimentary system in heterodont bivalves,” about his excellent anatomical work on bivalve stomachs. Also presenting from our team were Paula Mikkelsen, Dan Graf, and John Pfeiffer. More...
