Among animal phyla, the Ctenophores are more complex than sponges, about as complex as cnidarians (jellyfish, sea anemones, etc.), and less complex than bilaterians (which include almost all other animals). U… See more

For a phylum with relatively few species, ctenophores have a wide range of body plans. Coastal species need to be tough enough to withstand waves and swirling sediment particles, while some oceanic species ar… See more

Ctenophores are found in most marine environments: from polar waters at −2°C to the tropics at 30°C; near coasts and in mid-ocean; from the surface waters to the ocean depths at more than 7000 meters. The best-u… See more

The number of known living ctenophore species is uncertain since many of those named and formally described have turned out to be identical to species known under other scientific names. Claudia Mills estimates t… See more

Despite their fragile, gelatinous bodies, fossils thought to represent ctenophores – apparently with no tentacles but many more comb-rows than modern forms – have been found in Lagerstätten as far back as the early … See more