Peringia ulvae
Encyclopedia
Hydrobia ulvae, also known as Peringia ulvae, common name the Laver spire shell, is an Europe
an species
of very small aquatic snail with gill
s and an operculum
, a gastropod mollusk in the family Hydrobiidae
.
This is arguably a marine snail, but it is often also listed as a non-marine species because it tolerates brackish water
and lives in salt marsh
es and similar habitats.
When it is within the genus Peringia, this species is the type genus
of the genus Peringia.
, the Eastern Atlantic and the western Mediterranean Sea
, including:
The type locality is "on the shores of Flintshire
", Wales, United Kingdom.
in 1777. Pennant's original text (the type description) reads as follows:
"T." is an abbreviated word testa from Latin language, that means "shell".
The shell
is often heavily corroded, usually whitish with brown peristome present on the last whorl. The shell has 5-7 very weakly convex whorls
, that are regularly increasing but not always regularly rounded. The lip is attached to the last whorl.
The width of the shell is 2.5-3 mm. The height of the shell is 4-5.5 mm.
and saltwater, in estuaries and salt marsh
es. It is most common in the upper half of the intertidal zone
. It tolerates salinity
1.0-3.3 %.
Hydrobia ulvae seems to prefer more exposed localities with less vegetation than Hydrobia ventrosa
and Hydrobia neglecta
.
Hydrobia ulvae feeds on detritus
and it also consumes seaweeds directly.
It is dioecious
with sexes being easily identified through dissection
. On the west coast of Wales
this species has peaks of spawning activity in spring and autumn and produces planktotrophic larvae (veliger
) that remain in the plankton for up to four weeks before settlement. This period of development affords the potential for dispersal
to new habitats and mixing with geographically separate populations. The species provides an interesting case for molecular analysis
as the pelagic dispersal phase raises fascinating questions on gene flow
, differentiation, recruitment, and inbreeding
, but there remains the potential for self-recruitment of estuarine populations.
One of its natural predators is the Arctic barrel-bubble (Retusa obtusa).
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
an species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of very small aquatic snail with gill
Gill
A gill is a respiratory organ found in many aquatic organisms that extracts dissolved oxygen from water, afterward excreting carbon dioxide. The gills of some species such as hermit crabs have adapted to allow respiration on land provided they are kept moist...
s and an operculum
Operculum (gastropod)
The operculum, meaning little lid, is a corneous or calcareous anatomical structure which exists in many groups of sea snails and freshwater snails, and also in a few groups of land snails...
, a gastropod mollusk in the family Hydrobiidae
Hydrobiidae
Hydrobiidae, common name mud snails, is a large cosmopolitan taxonomic family of very small freshwater snails and brackish water snails that have an operculum, aquatic gastropod mollusks in the clade Littorinimorpha.- Distribution :...
.
This is arguably a marine snail, but it is often also listed as a non-marine species because it tolerates brackish water
Brackish water
Brackish water is water that has more salinity than fresh water, but not as much as seawater. It may result from mixing of seawater with fresh water, as in estuaries, or it may occur in brackish fossil aquifers. The word comes from the Middle Dutch root "brak," meaning "salty"...
and lives in salt marsh
Salt marsh
A salt marsh is an environment in the upper coastal intertidal zone between land and salt water or brackish water, it is dominated by dense stands of halophytic plants such as herbs, grasses, or low shrubs. These plants are terrestrial in origin and are essential to the stability of the salt marsh...
es and similar habitats.
When it is within the genus Peringia, this species is the type genus
Type genus
In biological classification, a type genus is a representative genus, as with regard to a biological family. The term and concept is used much more often and much more formally in zoology than it is in botany, and the definition is dependent on the nomenclatural Code that applies:* In zoological...
of the genus Peringia.
Distribution
This species occurs on the coasts of the Baltic SeaBaltic Sea
The Baltic Sea is a brackish mediterranean sea located in Northern Europe, from 53°N to 66°N latitude and from 20°E to 26°E longitude. It is bounded by the Scandinavian Peninsula, the mainland of Europe, and the Danish islands. It drains into the Kattegat by way of the Øresund, the Great Belt and...
, the Eastern Atlantic and the western Mediterranean Sea
Mediterranean Sea
The Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant...
, including:
- Great Britain
- Ireland
- The Netherlands
The type locality is "on the shores of Flintshire
Flintshire
Flintshire is a county in north-east Wales. It borders Denbighshire, Wrexham and the English county of Cheshire. It is named after the historic county of Flintshire, which had notably different borders...
", Wales, United Kingdom.
Description
This species was originally described by Welsh naturalist Thomas PennantThomas Pennant
Thomas Pennant was a Welsh naturalist and antiquary.The Pennants were a Welsh gentry family from the parish of Whitford, Flintshire, who had built up a modest estate at Bychton by the seventeenth century...
in 1777. Pennant's original text (the type description) reads as follows:
"T." is an abbreviated word testa from Latin language, that means "shell".
The shell
Gastropod shell
The gastropod shell is a shell which is part of the body of a gastropod or snail, one kind of mollusc. The gastropod shell is an external skeleton or exoskeleton, which serves not only for muscle attachment, but also for protection from predators and from mechanical damage...
is often heavily corroded, usually whitish with brown peristome present on the last whorl. The shell has 5-7 very weakly convex whorls
Whorl (mollusc)
A whorl is a single, complete 360° revolution or turn in the spiral growth of a mollusc shell. A spiral configuration of the shell is found in of numerous gastropods, but it is also found in shelled cephalopods including Nautilus, Spirula and the large extinct subclass of cephalopods known as the...
, that are regularly increasing but not always regularly rounded. The lip is attached to the last whorl.
The width of the shell is 2.5-3 mm. The height of the shell is 4-5.5 mm.
Habitat
Hydrobia ulvae is a widespread and abundant member of the benthic fauna of estuarine habitats and coastal brackish and salt waters. It is very common in brackish waterBrackish water
Brackish water is water that has more salinity than fresh water, but not as much as seawater. It may result from mixing of seawater with fresh water, as in estuaries, or it may occur in brackish fossil aquifers. The word comes from the Middle Dutch root "brak," meaning "salty"...
and saltwater, in estuaries and salt marsh
Salt marsh
A salt marsh is an environment in the upper coastal intertidal zone between land and salt water or brackish water, it is dominated by dense stands of halophytic plants such as herbs, grasses, or low shrubs. These plants are terrestrial in origin and are essential to the stability of the salt marsh...
es. It is most common in the upper half of the intertidal zone
Intertidal zone
The intertidal zone is the area that is above water at low tide and under water at high tide . This area can include many different types of habitats, with many types of animals like starfish, sea urchins, and some species of coral...
. It tolerates salinity
Salinity
Salinity is the saltiness or dissolved salt content of a body of water. It is a general term used to describe the levels of different salts such as sodium chloride, magnesium and calcium sulfates, and bicarbonates...
1.0-3.3 %.
Hydrobia ulvae seems to prefer more exposed localities with less vegetation than Hydrobia ventrosa
Hydrobia ventrosa
Ecrobia ventrosa, common name : the spire snail, is a European species of small brackish water snail with a gill and an operculum, an aquatic gastropod mollusk in the family Hydrobiidae.-Distribution:This species occurs on the coasts of:...
and Hydrobia neglecta
Hydrobia neglecta
Hydrobia acuta neglecta is an European subspecies of small brackish water snail with a gill and an operculum, an aquatic gastropod mollusk in the family Hydrobiidae.-Distribution:...
.
Hydrobia ulvae feeds on detritus
Detritus
Detritus is a biological term used to describe dead or waste organic material.Detritus may also refer to:* Detritus , a geological term used to describe the particles of rock produced by weathering...
and it also consumes seaweeds directly.
It is dioecious
Dioecious
Dioecy is the property of a group of biological organisms that have males and females, but not members that have organs of both sexes at the same time. I.e., those whose individual members can usually produce only one type of gamete; each individual organism is thus distinctly female or male...
with sexes being easily identified through dissection
Dissection
Dissection is usually the process of disassembling and observing something to determine its internal structure and as an aid to discerning the functions and relationships of its components....
. On the west coast of Wales
Wales
Wales is a country that is part of the United Kingdom and the island of Great Britain, bordered by England to its east and the Atlantic Ocean and Irish Sea to its west. It has a population of three million, and a total area of 20,779 km²...
this species has peaks of spawning activity in spring and autumn and produces planktotrophic larvae (veliger
Veliger
A veliger is the planktonic larva of many kinds of marine and freshwater gastropod molluscs, as well as most bivalve mollusks.- Description :...
) that remain in the plankton for up to four weeks before settlement. This period of development affords the potential for dispersal
Biological dispersal
Biological dispersal refers to species movement away from an existing population or away from the parent organism. Through simply moving from one habitat patch to another, the dispersal of an individual has consequences not only for individual fitness, but also for population dynamics, population...
to new habitats and mixing with geographically separate populations. The species provides an interesting case for molecular analysis
Molecular biology
Molecular biology is the branch of biology that deals with the molecular basis of biological activity. This field overlaps with other areas of biology and chemistry, particularly genetics and biochemistry...
as the pelagic dispersal phase raises fascinating questions on gene flow
Gene flow
In population genetics, gene flow is the transfer of alleles of genes from one population to another.Migration into or out of a population may be responsible for a marked change in allele frequencies...
, differentiation, recruitment, and inbreeding
Inbreeding
Inbreeding is the reproduction from the mating of two genetically related parents. Inbreeding results in increased homozygosity, which can increase the chances of offspring being affected by recessive or deleterious traits. This generally leads to a decreased fitness of a population, which is...
, but there remains the potential for self-recruitment of estuarine populations.
One of its natural predators is the Arctic barrel-bubble (Retusa obtusa).
Further reading
- Backeljau T. (1986). Lijst van de recente mariene mollusken van België [List of the recent marine molluscs of Belgium]. Koninklijk Belgisch Instituut voor Natuurwetenschappen: Brussels, Belgium. 106 pp.
- Fish J. D., Fish S. & Foley H. (2000). "The biology of mud snails with particular reference to Hydrobia ulvae". In: British Saltmarshes. Sherwood B. R., Gardiner B. G. & Harris T. (eds.) London, Linnean Society: 165-179.
- Gofas S., Le Renard J., Bouchet P. (2001). Mollusca, in: Costello, M.J. et al. (Ed.) (2001). European register of marine species: a check-list of the marine species in Europe and a bibliography of guides to their identification. Collection Patrimoines Naturels, 50: pp. 180-213.
- Haase M. (1993). "The genetic differentiation in three species of the genus Hydrobia and systematic implications (Caenogastropoda, Hydrobiidae)". MalacologiaMalacologiaMalacologia is a peer-reviewed scientific journal in the field of malacology, the study of mollusks. The journal publishes articles in the fields of molluscan systematics, ecology, population ecology, genetics, molecular genetics, evolution, and phylogenetics.The journal specializes in publishing...
35: 389-398. - Muller Y. (2004). Faune et flore du littoral du Nord, du Pas-de-Calais et de la Belgique: inventaire. [Coastal fauna and flora of the Nord, Pas-de-Calais and Belgium: inventory]. Commission Régionale de Biologie Région Nord Pas-de-Calais: France. 307 pp.