Sword of Venus

It reaches about 60–65 mm (2.4–2.6 in) in length and has a translucent, bluish body with two wing-like parapods used for slow movement. During development it retains a transparent, cartilaginous internal shell (pseudoconch) with five dentate ridges that resembles a “glass slipper” or gelatinous crystal-like structure often found washed up on beaches after the animal’s death, sometimes called a "venus' hoof".

The species inhabits waters concentrating around the extreme south-east United States, the Balearic Islands of Spain, Svalbard, and the offshores of Namibia, sometimes down to about 2,000 m (6,560 ft) depth, carried by currents. It can withstand temperatures of 13–27 °C (55–81 °F).

Reproduction and breeding takes place temporally from June to August. The animals are protandrous hermaphrodites, meaning male characteristics develop first, with individuals becoming female as they age; this is known as successive hermaphroditism. Reproduction takes place in the planktonic environment through the release of gametes and the development of veliger larvae (gastropod larvae).

== References ==

Cymbulia peronii often captures prey by having its oral organs open while drifting, and feeds on phytoplankton, mucus, diatoms and other chromists. It is a passive predator, and utilizes hair-like tentacles to sense and detect nearby prey.