Ilyanassa obsoleta
A common mud-flat snail with a dark brown periostracum.
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Ilyanassa obsoleta, commonly known as the eastern mudsnail, is a species of sea snail, a marine gastropod mollusk in the family Nassariidae, the nassa mud snails. It is notable for its abundance on mud flats and its role as a detritus feeder in intertidal and shallow subtidal zones.
Scientific classification
- KingdomAnimalia
- PhylumMollusca
- ClassGastropoda
- SubclassCaenogastropoda
- OrderNeogastropoda
- FamilyNassariidae
- GenusIlyanassa
- SpeciesIlyanassa obsoleta
Named by (Say, 1822)
Close relatives
Other species of Ilyanassa with a Codexery entry.
- Ilyanassa trivittata Ilyanassa trivittata
Sources: Wikipedia taxobox: Ilyanassa obsoleta (CC BY-SA 4.0) · order, family and genus agree with WoRMS AphiaID 467490 (CC BY 4.0)
How big is it?
Largest length in the source, 0.03 m, next to a 1.8 m person.
Diagram: drawn by Codexery, schematic shapes to scale (not a likeness). Length: Wikipedia: Ilyanassa obsoleta
Where the ilyanassa obsoleta has been recorded
Each dot is a place where the species has been observed and reported (5,512 records, half-degree grid) — not a modelled range. 63 inland records left out (institution coordinates).
Map: drawn by Codexery. Data: GBIF occurrence search (records CC0 / CC BY) · Natural Earth basemap (public domain) · place coordinates: Wikipedia (CC BY-SA 4.0)
Quick Facts
- Maximum shell length
- a little more than one inch, or about 28 mm / 1.1 in
- Indigenous distribution
- from Nova Scotia to Georgia in the United States
- Nonindigenous distribution
- West Coast of the United States
- Family
- Nassariidae
- Shell exterior color
- chalky white
- covered by a very dark brown
- closely adhering periostracum
Facts from the source article.
Background
The eastern mudsnail has a small shell with a slightly rough exterior, resulting from intersecting weak spiral and axial ribs. The shell features an oval aperture with a small notch or siphonal canal at the anterior end, a smooth inner lip with a partial shield, and a thin, smooth outer lip. The exterior of the shell is chalky white but is almost entirely covered by a very dark brown, closely adhering periostracum, except where the periostracum has eroded. The apex of the shell is almost always eroded, and the shell is often damaged by the acidic properties of the mud in which the animal lives.
This species is indigenous to the western Atlantic from Nova Scotia to Georgia in the United States, and has a nonindigenous distribution on the West Coast of the United States. It is very common on mud flats in the intertidal and shallow subtidal zones, in sounds and inlets. As a detritus feeder, it consumes whatever is found in the film on top of the mud where it lives, including many microscopic marine plants.
More in Marine Snails: Ceriths, Nassas and Conchs
Sources
Compiled from Wikipedia and the sources listed below. Text from Wikipedia is available under CC BY-SA 4.0; this entry is adapted from it.
- Wikipedia: Ilyanassa obsoleta (CC BY-SA 4.0).
- Classification: the source article's taxobox; order, family and genus checked against WoRMS, the World Register of Marine Species (CC BY 4.0).
- Occurrence records: GBIF (CC0 / CC BY). Basemap: Natural Earth (public domain).
- Word definitions: the , each quoted from its Wikipedia article.
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