Comb jellies (phylum Ctenophora) are mostly free-swimming organisms that appear like jellyfish, though some species may not swim but instead creep over the substrate.
The free-swimming species usually appear transparent and somewhat rounded. Many come with a pair of tentacles fringed with smaller tentacles (or tentilla), and most have eight strips (called comb rows) running down the length of their bodies. Each strip bears bands of hair-like projections (or cilia) which resemble a comb, and hence the name Ctenophora (which means "comb carrying" in Greek) and the common name comb jellies. These free-swimming comb jellies swim by beating their celia.
The species that do not swim usually appear flatten, much like flatworms. Most of them lack the comb-row, but they possess a pair of tentacles much like many of the free-swimming species. See this photo from Wikimedia which features numerous worm-like ctenophores extending their long tentacles on a sea star.
Ctenophores are carnivorous, and use their tentacles to capture their prey, which include copepods, jellyfish and other zooplankton. Most species have special cells called colloblasts that discharge adhesive substances to stick and capture their prey. Those that feed on jellyfish may incorporate the latter's sting cells into their tentacles to sting their prey.
References
The free-swimming species usually appear transparent and somewhat rounded. Many come with a pair of tentacles fringed with smaller tentacles (or tentilla), and most have eight strips (called comb rows) running down the length of their bodies. Each strip bears bands of hair-like projections (or cilia) which resemble a comb, and hence the name Ctenophora (which means "comb carrying" in Greek) and the common name comb jellies. These free-swimming comb jellies swim by beating their celia.
The species that do not swim usually appear flatten, much like flatworms. Most of them lack the comb-row, but they possess a pair of tentacles much like many of the free-swimming species. See this photo from Wikimedia which features numerous worm-like ctenophores extending their long tentacles on a sea star.
Ctenophores are carnivorous, and use their tentacles to capture their prey, which include copepods, jellyfish and other zooplankton. Most species have special cells called colloblasts that discharge adhesive substances to stick and capture their prey. Those that feed on jellyfish may incorporate the latter's sting cells into their tentacles to sting their prey.
References
- 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 20, 2013, from http://www.marinespecies.org.
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