Philine aperta and Philine quadripartita have long been treated as synonyms. However, according to Price et al. (2011), based on anatomy, there are two distinct species, the first one in South Africa and Mozambique, the second one in European seas. [1]
Distribution
This species can be found in the eastern Atlantic Ocean from northern Europe to southern Africa and is also found in the Pacific and Indian Oceans. It lives subtidally to several hundreds of metres underwater; in tropical waters it is found in deeper water.[2] In southern Africa it occurs from Saldanha Bay, West coast to Mozambique, subtidal to 100 m. [3]
Description
The body length of the adult is 60–70 mm, up to 100 mm. [3]
Philine aperta is a sturdy, solid-bodied animal, white to cream in colour, with an internal shell and a folded appearance. It grows up to 100 mm in length.[4]
The shell is internal and fully covered by the animal’s body. The body is divided into a head shield, which is flattened for burrowing in sandy substrates, a posterior shield that overlies the viscera and internal shell, and two lateral lobes, one on each side. The internal shell is thin and translucent. [3]
The somewhat translucent animal is uniformly milky white to yellowish. [3]
Ecology
Philine aperta is an active, sand-dwelling, predatory species; it eats small molluscs and worms which are swallowed whole, and then crushed in its gizzard. The animal secretes sulphuric acid to deter predators.
Its egg masses are translucent, sausage-shaped and are attached to sandy bottoms by long mucous threads.