Podocoryna carnea M. Sars, 1846

The colonies of this species have feeding polyps (gastrozooids), reproductive polyps (gonozooids), and defensive polyps (dactylozooids), although the dactylozooids may be absent depending on the substrate the colony is growing on. The gastrozooids are usually 1–3 mm high and have 6–19 tentacles. The gonozooids are slender and smaller compared to the gastrozooids and usually have less tentacles (4–10). Spines may be present in the colony, depending on the substrate and exposure to abrasive conditions. When they are present they are small, smooth, and are never distributed in groups. Young colonies that lack gonozooids are not identifiable to species.

Adult hydromedusae are smaller than 2.0 mm high and wide. When fully mature, each hydromedusa has 8 tentacles, the lowest number of all Norwegian species of Podocoryna. All the tentacles are similar in structure and length. The mouth has four lips, each ending in one cluster of stinging cells. Young medusae have at least 4–5 tentacles when they are liberated.

The colonies of P. carnea grow preferably on snail shells inhabited by living snails or hermit crabs. When the colonies grow on living snails, these are often members of genus Tritia, although colonies growing on Calliostoma snails have also been observed. When the colonies grow on hermit crabs they are less specific. The preferred depth for the hydroid colonies is 0–180 m. Very little is known about the biology and ecology of the hydromedusae of P. carnea, because they are only rarely collected in standard plankton nets.

The hydromedusae of P. carnea have rarely been recorded and their distribution is unknown. The observations of the colonies are more common and include western and southern Norway, Sweden, Denmark, and the British Isles.