''Cerithideopsis scalariformis'', commonly known as the ladder hornsnail, is a species of

sea snail Sea snail is a common name for slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the ...

, a marine

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

mollusk in the family Potamididae. This amphibious species occurs in the western Atlantic Ocean, the Caribbean Sea and the Gulf of Mexico. The maximum recorded shell length is .

Description

Like other members of its genus, the ladder hornsnail has an elongated, spirally coiled shell. The

radula The radula (, ; plural radulae or radulas) is an anatomical structure used by molluscs for feeding, sometimes compared to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food ...

, the rasping structure used in feeding, lacks cusps on the underside of its rachidian tooth. This species is usually some shade of grey, the transverse sculpturing often being eroded and whitish. It grows to a maximum length of .Welch J. J. (2010). "The "Island Rule" and Deep-Sea Gastropods: Re-Examining the Evidence". '' PLOS One'' 5(1): e8776. .

Distribution and habitat

This species is native to the warm waters of the tropical and subtropical western Atlantic Ocean, the Caribbean Sea and the Gulf of Mexico. Its range includes the coast of Georgia and the west and east coasts of Florida, including the

Indian River Lagoon The Indian River Lagoon is a grouping of three lagoons: the Mosquito Lagoon, the Banana River, and the Indian River, on the Atlantic Coast of Florida; one of the most biodiverse estuaries in the Northern Hemisphere and is home to more than 4,300 ...

. It is an amphibious species, living in mud above and below high water mark. Within its range, it is plentiful in tidal creeks, estuaries, salt marshes and mangrove swamps. It is tolerant of wide variations in temperature and is resistant to desiccation.

Ecology

The ladder hornsnail feeds on

detritus In biology, detritus () is dead particulate organic material, as distinguished from dissolved organic material. Detritus typically includes the bodies or fragments of bodies of dead organisms, and fecal material. Detritus typically hosts commun ...

and

microalgae Microalgae or microphytes are microscopic algae invisible to the naked eye. They are phytoplankton typically found in freshwater and marine systems, living in both the water column and sediment. They are unicellular species which exist indiv ...

. It is predated by mud crabs and probably also by fiddler crabs,

blue crab Blue crab may refer to: * Blue Crab 11, an American sailboat design * ''Callinectes sapidus'' – Chesapeake or Atlantic blue crab of the West Atlantic, introduced elsewhere * ''Cardisoma guanhumi'' – blue land crab of the West Atlantic * '' Disc ...

s, clapper rails, other wading birds,

opossum Opossums () are members of the marsupial order Didelphimorphia () endemic to the Americas. The largest order of marsupials in the Western Hemisphere, it comprises 93 species in 18 genera. Opossums originated in South America and entered North ...

s and raccoons. Juveniles sometimes exhibit incomplete tentacles, and this may be the result of attacks by killifish. In the Indian River Lagoon, breeding takes place between September and November, when jelly-clad spirals of bright green eggs are produced. The eggs hatch after about three weeks and the young develop directly into juveniles without a free-living larval stage. The juveniles tend to live underwater while the adults mostly live above high water mark. The juveniles reach maturity by August or September. Over time, the shells of adults become eroded and they are often parasitized by trematodes; most individuals probably die in their second winter.

References

Reid D.G. & Claremont M. (2014) ''The genus Cerithideopsis Thiele, 1929 (Gastropoda: Potamididae) in the Indo-West Pacific region''. Zootaxa 3779(1): 61–80
{{DEFAULTSORT:Cerithideopsis Scalariformis Potamididae Gastropods described in 1825 Taxa named by Thomas Say