Macroschisma productum

Macroschisma productum, common name the elongated keyhole limpet, is a species of sea snail, a marine gastropod mollusk in the family Fissurellidae, the keyhole limpets and slit limpets.

Description

The shell is elongated and narrowly oblong, elevated dorsally and convex, with flattened sides and a strongly sinuous margin. The apical opening (foramen) is very long, triangular, and expanded posteriorly.

The shell is thin, whitish, and may be variegated with pale brown markings. Its surface shows fine radial striae crossed by faint concentric lines, producing an obsolete decussate sculpture.

The anterior end is narrowed and produced, while the posterior extremity is rounded and elevated.

SThe shell is very elongate and depressed posteriorly by a broad flat rib and may be drawn out into a beak-like point. The foramen is wide anteriorly and situated near the front margin.

The shell resembles other members of the family Fissurellidae in having compressed sides and elevated extremities, but is distinguished by its marked posterior prolongation and unusually long opening.

Distribution

This marine species occurs in southern Australia and the western Indian Ocean.

In Australia it has been recorded from Port Lincoln, South Australia, including deep-water habitats.

In Madagascar, it has been reported from Nosy Nasatrana, where specimens were collected on the beach.

External links

• . Gastropods.com.