Ocnus lacteus

Ocnus lacteus is a species of sea cucumber in the family Cucumariidae.

Ocnus lacteus
Conservation status
Not evaluated (IUCN 3.1)[1]
Scientific classification
Kingdom:	Animalia
Phylum:	Echinodermata
Class:	Holothuroidea
Order:	Dendrochirotida
Family:	Cucumariidae
Genus:	Ocnus
Species:	O. lacteus
Binomial name
Ocnus lacteus Forbes and Goodsir, 1839
Synonyms[2]
Holothuria lactea Forbes & Goodsir, 1839 Cucumaria lactea (Forbes, 1839)

Description

Ocnus lacteus is 1–4 cm (0.39–1.57 in) long. It crawls on rocks at shallow depths, using five rows of long tube feet. At the head are ten branching tentacles for catching food.^[3] It is white (hence the specific name lacteus, "milky"), with numerous spicules that each contain four holes.^[4]

Reproduction

Ocnus lacteus are gonochoric and each individual has only one gonad. Spawning and fertilization are external; some exhibit brooding. Embryos develop into planktotrophic larvae (auricularia) then into doliolaria (barrel-shaped) which later metamorphose into juvenile sea cucumbers.^[1]

Distribution and habitat

It is found in western Ireland.^[5] It lives in northerly waters from the Arctic to the Mediterranean.^[2] It lives at depths up to 200 m (660 ft), living on the seafloor and crawling over algae and seaweed.^[6]