Lamp shells (phylum Brachiopoda) are solitary, clam-like animals with a two-part shell (i.e. two valves). However, unlike a clam which has a left valve and a right valve (based on how the valves are oriented to the body), a lamp shell has a dorsal (or "upper") valve and a ventral (or "lower") valve. In addition, clams have a ligament that joins the valves near the hinge, which forces the two valves open when the adductor muscles relax. Brachiopods lack this ligament, and hence their shells often remain close even after the animal is dead. They got their common name as the shells of some species somewhat resemble pottery oil lamps.
Most lamp shells attach themselves to hard substrates or anchor themselves in soft substrates with a stalk-like structure called a pedicle, while others may cemented themselves to the substrate or lie freely.
They have a crown of tentacles (known as a lophophore) with fine hair-like structures (or cilia) to generate a current for the filtering of plankton and other tiny organic particles to feed on.
Most species are of separate sexes, and to reproduce, the males will release the sperm into the water, while the females may either release their eggs into the water for external fertilisation, or brood fertilised eggs in brood chambers until they hatch into planktonic larvae.
Lingula anatina is sometimes seen burrowed in sandy or muddy substrates on our shores.
References
Most lamp shells attach themselves to hard substrates or anchor themselves in soft substrates with a stalk-like structure called a pedicle, while others may cemented themselves to the substrate or lie freely.
They have a crown of tentacles (known as a lophophore) with fine hair-like structures (or cilia) to generate a current for the filtering of plankton and other tiny organic particles to feed on.
Most species are of separate sexes, and to reproduce, the males will release the sperm into the water, while the females may either release their eggs into the water for external fertilisation, or brood fertilised eggs in brood chambers until they hatch into planktonic larvae.
Lingula anatina is sometimes seen burrowed in sandy or muddy substrates on our shores.
References
- Emig C. C., A. Fernando, & M. A. Bitner. 2011. Brachiopoda world database. Retrieved Feb 4, 2013, from http://www.marinespecies.org/brachiopoda
- Ruppert, E.E. and R.D. Barnes. 1991. Invertebrate Zoology (International Edition). Saunders College Publishing. U.S.A. 1056 pp.
- Tan, L. W. H. & P. K. L. Ng. 1988. A Guide to Seashore Life. Singapore Science Centre. Singapore. 160 pp.
- World Register of Marine Species. 2012. Retrieved Feb 4, 2013, from http://www.marinespecies.org.
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