|A shell of Amphibola crenata|
Amphibola crenata (titiko in the Māori language or mud-flat snail in English) is a species of air breathing snail with an operculum, a pulmonate gastropod mollusc which lives in a habitat that is intermediate between the land and the sea, not entirely terrestrial and not entirely marine. 
This is not a true land snail, but it is also not a true sea snail. Unlike almost all other snails that have opercula, this species breathes air. It is common in New Zealand.
- Description 1
- Feeding habits 2.1
- Human use 3
- References 4
- External links 5
The thick shell of this species is about 20 mm in size.
Amphibola crenata is a curiosity, as it seems to represent a transitional state between marine and terrestrial gastropods. The mantle is employed as a lung, and therefore immersion of the animal in sea water is of secondary importance, and occurs for not more than an hour at each high tide.
This snail is a detritus or deposit feeder. It extracts bacteria, diatoms and decomposing matter from the surface sand. It egests the sand and a slimy secretion that is a rich source of food for bacteria.
In the past this species was an important food for the Māori.
- Schumacher H. C. F. (1817). Essai Vers test. 58: 190.
- Rosenberg, G. (2011). Amphibola crenata (Gmelin, 1791). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=590660 on 2012-04-06
- Powell A. W. B. (1979). William Collins Publishers Ltd, Auckland, New Zealand, ISBN 0-00-216906-1
- Rosenberg, G. 1992. Encyclopedia of Seashells. Dorset: New York. 224 pp. page(s): 125
- Golding R.E., Ponder W.F. & Byrne M. 2007. Taxonomy and anatomy of Amphiboloidea (Gastropoda: Heterobranchia: Archaeopulmonata). Zootaxa 1476: 1-50
- 1966 Te Ara encyclopedia entry