Cnidaria vs. Ctenophora — What's the Difference?

Includes jellyfish, corals, and sea anemones.

A phylum of marine animals known as comb jellies.

Found in marine and freshwater environments.

Lacks stinging cells, using sticky cells called colloblasts instead.

Uses specialized stinging cells called nematocysts.

Exclusively marine and solitary.

Can switch between polyp and medusa forms.

Has a unique apical organ to sense direction.

A phylum of aquatic animals with stinging cells.

Propels itself using rows of cilia resembling combs.

Cnidaria () is a phylum under kingdom Animalia containing over 11,000 species of aquatic animals found both in freshwater and marine environments, predominantly the latter. Their distinguishing feature is cnidocytes, specialized cells that they use mainly for capturing prey.

Ctenophora (; singular ctenophore, or ; from Ancient Greek: κτείς, romanized: kteis, lit. 'comb' and φέρω, pherō, 'to carry'; commonly known as comb jellies) comprise a phylum of invertebrate animals that live in marine waters worldwide. They are notable for the groups of cilia they use for swimming (commonly referred to as "combs"), and they are the largest animals to swim with the help of cilia.

Cnidarian

A phylum of invertebrates, commonly ellipsoidal in shape, swimming by means of eight longitudinal rows of paddles. They are commonly called the comb jellies, because the separate paddles somewhat resemble combs. This phylum was formerly classified as a subdivision (class) within the Cœlenterata.

A comprehensive group equivalent to the true Cœlenterata, i. e., exclusive of the sponges. They are so named from presence of stinging cells (cnidae) in the tissues. See Coelenterata.

Comb jellies; sea acorns; a small phylum formerly considered a class of Coelenterata

Hydras; polyps; jellyfishes; sea anemones; corals

Ctenophores use colloblasts, sticky cells on their tentacles or body, to trap plankton and small prey.

Cnidarians can form large colonies like coral reefs, while ctenophores are typically solitary.

Cnidarians have nematocysts (stinging cells) and can switch between polyp and medusa forms, while ctenophores have ciliated comb rows and sticky colloblasts.

No, ctenophores lack venom and pose no stinging threat to humans.

Nematocysts inject venom into prey, allowing cnidarians to capture and immobilize them.

Cnidarians move by pulsating their bell or floating passively, while ctenophores use rows of cilia for propulsion.

While all ctenophores are marine, some cnidarians can also live in freshwater environments.

Both groups exhibit radial symmetry, but ctenophores also have an apical organ for balance.

Ctenophore cilia rows, or "combs," are used for locomotion, refracting light to create a shimmering effect.

Cnidarians often form reefs or act as predators, while ctenophores are primarily open-water planktonic predators.

Cnidarians can have both polyp and medusa stages, while ctenophores generally have one form.

Corals belong to the phylum Cnidaria.

The nerve net helps cnidarians detect changes in their environment and coordinate simple movements.

Yes, many ctenophores can produce light through bioluminescence.

No, comb jellies belong to a separate phylum and are not considered true jellyfish.