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

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of sea snail, a marine gastropod

mollusk Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...

in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Potamididae ''Potamididae'', common name potamidids (also known as horn snails or mudwhelks) are a family of small to large brackish water snails that live on mud flats, mangroves and similar habitats. They are amphibious gastropod molluscs in the superfam ...

. This amphibious species occurs in the western Atlantic Ocean, the Caribbean Sea and the

Gulf of Mexico The Gulf of Mexico ( es, Golfo de México) is an ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of the United ...

. The maximum recorded

shell Shell may refer to: Architecture and design * Shell (structure), a thin structure ** Concrete shell, a thin shell of concrete, usually with no interior columns or exterior buttresses ** Thin-shell structure Science Biology * Seashell, a hard o ...

length is .

Description

Like other members of its genus, the ladder hornsnail has an elongated, spirally coiled shell. The radula, 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 The Caribbean Sea ( es, Mar Caribe; french: Mer des Caraïbes; ht, Lanmè Karayib; jam, Kiaribiyan Sii; nl, Caraïbische Zee; pap, Laman Karibe) is a sea of the Atlantic Ocean in the tropics of the Western Hemisphere. It is bounded by Mexico ...

and the

. Its range includes the coast of

Georgia Georgia most commonly refers to: * Georgia (country), a country in the Caucasus region of Eurasia * Georgia (U.S. state), a state in the Southeast United States Georgia may also refer to: Places Historical states and entities * Related to the ...

and the west and east coasts of

Florida Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and to ...

, including the Indian River Lagoon. It is an amphibious species, living in mud above and below high water mark. Within its range, it is plentiful in

tidal creek A tidal creek or tidal channel is a narrow inlet or estuary that is affected by the ebb and flow of ocean tides. Thus, it has variable salinity and electrical conductivity over the tidal cycle, and flushes salts from inland soils. Tidal cree ...

estuaries An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environmen ...

salt marsh A salt marsh or saltmarsh, also known as a coastal salt marsh or a tidal marsh, is a coastal ecosystem in the upper coastal intertidal zone between land and open saltwater or brackish water that is regularly flooded by the tides. It is domin ...

es and

mangrove A mangrove is a shrub or tree that grows in coastal saline or brackish water. The term is also used for tropical coastal vegetation consisting of such species. Mangroves are taxonomically diverse, as a result of convergent evolution in severa ...

swamps. It is tolerant of wide variations in temperature and is resistant to desiccation.

Ecology

The ladder hornsnail feeds on detritus and microalgae. It is predated by

mud crab Mud crab may refer to any crab that lives in or near mud, such as: *'' Scylla serrata'' *'' Scylla tranquebarica'' *'' Scylla paramamosain'' *'' Scylla olivacea'' *Members of the family Panopeidae, such as '' Panopeus herbstii'' *Members of the ...

s and probably also by

fiddler crab The fiddler crab or calling crab may be any of more than one hundred species of semiterrestrial marine crabs in the family Ocypodidae, well known for their sexually dimorphic claws; the males' major claw is much larger than the minor claw, while ...

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 * '' Dis ...

clapper rail The clapper rail (''Rallus crepitans'') is a member of the rail family, Rallidae. The taxonomy for this species is confusing and still being determined. It is a large brown rail that is resident in wetlands along the Atlantic coasts of the easte ...

s, other wading birds, opossums and

raccoon The raccoon ( or , ''Procyon lotor''), sometimes called the common raccoon to distinguish it from other species, is a mammal native to North America. It is the largest of the procyonid family, having a body length of , and a body weight of ...

s. Juveniles sometimes exhibit incomplete tentacles, and this may be the result of attacks by

killifish A killifish is any of various oviparous (egg-laying) cyprinodontiform fish (including families Aplocheilidae, Cyprinodontidae, Fundulidae, Profundulidae and Valenciidae). All together, there are 1,270 species of killifish, the biggest family ...

. 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

trematode Trematoda is a class of flatworms known as flukes. They are obligate internal parasites with a complex life cycle requiring at least two hosts. The intermediate host, in which asexual reproduction occurs, is usually a snail. The definitive h ...

s; 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