Paedoclione doliiformis is a species of sea angel, a small floating sea slug, a pelagic marine gastropod mollusk in the family Clionidae.
Paedoclione doliiformis is the only species in the genus Paedoclione.[1]
The generic name is a reference to the paedomorphic habit of this genus, which retains many larval features throughout its life.[2]
Paedoclione doliiformis was originally described by Charles Haskell Danforth in 1907. It was not collected by zoologists for the next 61 years. It was rediscovered in 1968 by Lalli (1972).[3]
The type locality of Paedoclione doliiformis is Casco Bay, Portland, Maine.
The distribution includes St. Margarets Bay, Nova Scotia, the Gulf of Maine[2] [3] and possibly elsewhere.
Paedoclione doliiformis retains juvenile (larval) physical characteristics for the whole of its life.[3] This is called neoteny (a kind of pedomorphosis).[3]
The body length is up to 1.5 mm.[1] Paedoclione doliiformis has no shell.[1]
It is a gelatinous, mostly transparent pteropod, and it only has a shell in its embryonic stage.
The orange visceral sac is confined to the anterior part.
Mating is carried out ventrally for mutual fertilization. The following spring, this results in a free-floating, gelatinous egg mass.
Eggs hatch after three days, and the shell is retained until the 11th day.[2]
Paedoclione doliiformis feeds exclusively on Limacina helicina and on Limacina retroversa, but solely on juveniles with shells smaller than 1 mm.[4] Its abundance is closely linked to that of its prey.[2]