|
Family Olividae - olive shells
|
Order |
: |
|
||
Class |
: |
Gastropoda |
||
No. of Genera in Ref. |
: |
|||
No. of Species in Ref. |
: |
|||
Environment |
: |
Fresh : No |
Brackish : No |
Marine : Yes |
||
Aquarium |
: |
|||
First Fossil Record |
: |
|||
Remark |
: |
Shell thick and porcelaneous, elongate-ovate, with a short spire, a lrage body whorl and usually deeply channeled sutures. Surface smooth, highly polishes and often vividly coloured. No periostracum. Aperture elongate, with a wide and short anterior siphonal canal and an indistinct posterior notch. Outer lip slightly thickened in adult stage, smooth. Inner lip calloused, often eith fine transverse lirae, and with oblique, columellar grooves anteriorly. Columellar callus usually bordered posteriorly by a distinct, calloused spiral band. Operculum absent. Head broad but poorly defined, with an extensible snout and reduced tentacles. Eyes small to absent. Foot large and wide, with a distinct, more or less triangular to shield shaped anterior part. Posterior part of the foot voluminous, partially reflecting over the shell when expanded. Mantle with a long, cylindrical fleshy siphon anteriorly. Sand-dwelling, active animals inhabiting the intertidal and shallow sublittoral areas of most tropical or subtropical seas. Crawl on top of the substrate, or most commonly below the surface, with only the tip of the fleshy siphon exposed, leaving a characteristic trail. Carnivores or scavengers, mostly feeding on various invertebrates which are captured and held with the large foot. Sexes separate, fertilization internal. Eggs released in small capsules which may be free-floating, attached together and half buried in the sediment, or even fixed with mucus to the shell of a living, burrowing bivalve (Ref. 349). |
||
Etymology |
: |
|||
Division |
: |
|||
Reproductive guild |
: |
|||
Typical activity level |
: |
|||
Main Ref. |
: |
|||
Coordinator |
: |
|||