Terrestrial molluscs or land molluscs (mollusks) are an
ecological group that includes all
molluscs that live on
land in contrast to
freshwater
Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. Although the term specifically excludes seawater and brackish water, it does incl ...
and
marine
Marine is an adjective meaning of or pertaining to the sea or ocean.
Marine or marines may refer to:
Ocean
* Maritime (disambiguation)
* Marine art
* Marine biology
* Marine debris
* Marine habitats
* Marine life
* Marine pollution
Military ...
molluscs. They probably first occurred in the
Carboniferous
The Carboniferous ( ) is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period million years ago ( Mya), to the beginning of the Permian Period, million years ago. The name ''Carboniferou ...
, arising from
freshwater ones.
Characteristics
This group includes
land snails and
land slugs. Loss of the shell has taken place many times in different groups that are not evolutionarily closely related, and land snails and slugs are most often treated together as a single group in specialized
malacological
Malacology is the branch of invertebrate zoology that deals with the study of the Mollusca (mollusks or molluscs), the second-largest phylum of animals in terms of described species after the arthropods. Mollusks include snails and slugs, clams, ...
literature.
[Barker G. M. (ed.) ]
The biology of terrestrial molluscs
'. CABI Publishing, 2001, 558 pp. .[Barker G. M. (ed.) ]
Natural enemies of terrestrial molluscs
'. CABI Publishing, 2004, 644 pp. .
All terrestrial molluscs belong to the class
Gastropoda. However, colonization of the land took place several times during the
evolutionary
Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variati ...
past, and as a result terrestrial molluscs are classified in several different, often not closely related, gastropod
taxa.
Terrestrial mollusks comprise about 35 thousand species, most of which belong to the order (in some sources suborder or infraorder)
Stylommatophora
Stylommatophora is an orderPhilippe Bouchet, Jean-Pierre Rocroi, Bernhard Hausdorf, Andrzej Kaim, Yasunori Kano, Alexander Nützel, Pavel Parkhaev, Michael Schrödl and Ellen E. Strong. 2017. Revised Classification, Nomenclator and Typification ...
.
Terrestrial molluscs occur across most of the planet, with the exception of
Antarctica
Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest cont ...
and some islands. They inhabit a wide range of ecosystems, from
desert
A desert is a barren area of landscape where little precipitation occurs and, consequently, living conditions are hostile for plant and animal life. The lack of vegetation exposes the unprotected surface of the ground to denudation. About on ...
s and
tundras to
rainforests.
In terms of survival, this group of species is currently one of the most threatened; there are more known species
extinctions of terrestrial molluscs than in any other group of organisms.
[Cameron R. ''Slugs and snails''. HarperCollins Publishers, London, 2016, 508 pp. .]
Taxonomic diversity
According to an estimate from Cameron,
of the 409 existing gastropod
families, 119 include terrestrial molluscs. Among these 119 families, 104 are
Stylommatophora
Stylommatophora is an orderPhilippe Bouchet, Jean-Pierre Rocroi, Bernhard Hausdorf, Andrzej Kaim, Yasunori Kano, Alexander Nützel, Pavel Parkhaev, Michael Schrödl and Ellen E. Strong. 2017. Revised Classification, Nomenclator and Typification ...
, 7 are terrestrial
pulmonates other than stylommatophorans, and 8 are
operculates (formerly "
prosobranchs", molluscs with an
operculum, a group that primarily consists of
marine snails).
"Prosobranchs"
*
Cyclophoroidea (up to 10 families in different classifications)
*
Helicinidae,
Proserpinellidae
Proserpinellidae is a taxonomic family of land snails with an operculum, terrestrial gastropod mollusks in the superfamily Helicinoidea (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005).
This family has no subfamili ...
and
Proserpinidae
Proserpinidae is a taxonomic family of small land snails with an operculum, gastropod mollusks in the superfamily Helicinoidea
Helicinoidea is a taxonomic superfamily of land snails that have an operculum. In other words, they are terres ...
(in the superfamily
Helicinoidea
Helicinoidea is a taxonomic superfamily of land snails that have an operculum. In other words, they are terrestrial operculate gastropod mollusks. They are in the superfamily Neritoidea and are quite closely related to the marine and freshwater ...
)
*
Pomatiidae (in the superfamily
Littorinoidea
Littorinoidea are a superfamily of both sea snails and land snails which have a gill and an operculum, terrestrial and marine gastropod mollusks in the clade Littorinimorpha.
The terrestrial family within this group, the Pomatiidae, are some ...
, which consist mainly of
marine snails)
*
Assimineidae
Assimineidae is a family of minute snails, also known as palmleaf snails, with an operculum, gastropod mollusks or micromollusks in the superfamily Rissoidae. Many of these very small snails live in intermediate habitats, being amphibious betwee ...
and
Truncatellidae
Truncatellidae, common name the "looping snails", is a family of small amphibious snails, with gills and an operculum, semi-marine gastropod mollusks or micromollusks.
Shell description
This family of snails have small shells which lose thei ...
(in the superfamily
Truncatelloidea, which consist mainly of aquatic snails; most species semi-marine)
"Pulmonates"
*
Amphiboloidea
Amphiboloidea is a taxonomic superfamily of air-breathing land snails.
Distribution
Amphibolids are found in Indo-Pacific intertidal mangrove, saltmarsh and estuarine mudflat habitats.
Taxonomy 2005 taxonomy
According to the taxonomy of t ...
(three families of land and semi-marine snails)
*
Ellobioidea
Ellobiidae, common name the hollow-shelled snails, is a family of small air-breathing land snails, terrestrial pulmonate gastropod mollusks in the clade Eupulmonata.Bouchet, P. (2012). Ellobiidae. Accessed through: World Register of Marine Spec ...
(
Ellobiida
Ellobiida is an order of gastropods belonging to the class Gastropoda.
Families:
* Ellobiidae
Ellobiidae, common name the hollow-shelled snails, is a family of small air-breathing land snails, terrestrial pulmonate gastropod mollusks in the ...
) (1-5 families in different classifications, some of the species live in
litoral both in marine and terrestrial habitats)
*
Systellommatophora (3 families of land and semi-marine slugs)
*
Stylommatophora
Stylommatophora is an orderPhilippe Bouchet, Jean-Pierre Rocroi, Bernhard Hausdorf, Andrzej Kaim, Yasunori Kano, Alexander Nützel, Pavel Parkhaev, Michael Schrödl and Ellen E. Strong. 2017. Revised Classification, Nomenclator and Typification ...
(more than 100 families of land snails and slugs)
Best known terrestrial malacologists
*
Oskar Boettger
*
Jacques Philippe Raymond Draparnaud
*
Wilhelm Kobelt
Wilhelm Kobelt (20 February 1840 – 26 March 1916) was a German zoologist born in Alsfeld, Grand Duchy of Hesse. He specialized in the field of malacology.
Kobelt is remembered for his work as curator of the Senckenberg Museum in Frankfurt am ...
*
Henry Augustus Pilsbry
*
Emil Adolf Rossmässler
Emil Adolf Rossmässler (''Emil Adolf Roßmäßler'', ''Emil Adolph Roßmäßler'') (March 3, 1806 in Leipzig – April 8, 1867 in Leipzig) was a German biologist. With Otto Eduard Vincenz Ule and Karl Johann August Müller, he was co-founder of t ...
*
Heinrich Simroth
Heinrich Rudolf Simroth (10 May 1851 Riestedt (now a part of Sangerhausen) – 31 August 1917 Gautzsch near Leipzig), was a German zoologist and malacologist. He was a professor of zoology in Leipzig.
Academic career: 1888–1917 University of ...
*
Carl Agardh Westerlund
Carl Agardh Westerlund (12 January 1831 – 28 February 1908 in Ronneby) was a Swedish malacologist.
Biography
Westerlund was born at Berga in Kalmar County, Sweden.
He became a student in Uppsala University in 1853 and studied at Lund Uni ...
See also
*
Land snail
*
Land slug
*
Stylommatophora
Stylommatophora is an orderPhilippe Bouchet, Jean-Pierre Rocroi, Bernhard Hausdorf, Andrzej Kaim, Yasunori Kano, Alexander Nützel, Pavel Parkhaev, Michael Schrödl and Ellen E. Strong. 2017. Revised Classification, Nomenclator and Typification ...
*
Freshwater mollusc
*
Freshwater snail
*
Sea snail
References
Most important literature
* Barker G. M. (ed.)
The biology of terrestrial molluscs'. CABI Publishing, 2001, 558 pp. .
* Cameron R. ''Slugs and snails''. HarperCollins Publishers, London, 2016, 508 pp. {{ISBN, 978-0-00-711301-9.
Mollusc ecology
Molluscs by adaptation