Pleioptygma
Encyclopedia
Pleioptygma is a genus
of large sea snail
s, marine
gastropod mollusks in the superfamily Muricoidea
.
Pleioptygma is the type genus of the family Pleioptygmatidae and it is the only genus in the family Pleioptygmatidae.
word "pleios", which means "full" and from the Greek word "ptygma", which means "fold". This is a reference to the numerous folds on the columella of the shell.
.
The type description of the genus Pleioptygma by Timothy Abbott Conrad
(1863) reads as follows:
Although the shell of these gastropods looks similar to that of mitrids (family Mitridae
), they are unrelated enough to require their own family.
The family Pleioptygmatidae has been defined based on the anatomy of the only extant species Pleioptygma helenae
: The foot is relatively large in comparion to the size of the shell. Also the snout
is relatively large. The foregut
(of the digestive system
) is different from other families within the Muricoidea. The proboscis
is introvert, with a proboscis bulb that has an extreme thick wall. The proboscis bulb is connected directly to the buccal mass. There is no epiproboscis.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of large sea snail
Sea snail
Sea snail is a common name for those snails that normally live in saltwater, marine gastropod molluscs....
s, marine
Marine (ocean)
Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology...
gastropod mollusks in the superfamily Muricoidea
Muricoidea
Muricoidea is a taxonomic superfamily of predatory sea snails, marine gastropod mollusks in the clade Neogastropoda.This superfamily includes the murex snails, the chank snails, the true whelks, the dove snails, the crown conchs and busycon whelks, the spindle and tulip snails, the volutes and...
.
Pleioptygma is the type genus of the family Pleioptygmatidae and it is the only genus in the family Pleioptygmatidae.
Etymology
The generic name Pleioptygma is composed from the GreekGreek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
word "pleios", which means "full" and from the Greek word "ptygma", which means "fold". This is a reference to the numerous folds on the columella of the shell.
Description
In the genus Pleioptygma, the shell is medium to large in size. The shell has mainly spiral sculptureSculpture (mollusc)
The sculpture of a mollusc shell is the three-dimensional ornamentation on the outer surface, as distinct from the basic shape of the shell itself or colouration. Sculpture may be concave as well as convex. Sometimes it has microscopic detail. Sculpture refers to the calcareous outer layer, not the...
.
The type description of the genus Pleioptygma by Timothy Abbott Conrad
Timothy Abbott Conrad
Timothy Abbott Conrad was an American geologist, malacologist and carcinologist.- External links :* at Internet Archive...
(1863) reads as follows:
Although the shell of these gastropods looks similar to that of mitrids (family Mitridae
Mitridae
Mitridae, known as mitre shells, are a taxonomic family of sea snails, widely distributed marine gastropod molluscs in the clade Neogastropoda....
), they are unrelated enough to require their own family.
The family Pleioptygmatidae has been defined based on the anatomy of the only extant species Pleioptygma helenae
Pleioptygma helenae
Pleioptygma helenae is a species of sea snail, a marine gastropod mollusk in the family Pleioptygmatidae.It is the only known living species in this genus and the only extant species in the family Pleioptygmatidae.-Distribution:Honduras....
: The foot is relatively large in comparion to the size of the shell. Also the snout
Snout
The snout, or muzzle, is the protruding portion of an animal's face, consisting of its nose, mouth, and jaw.-Terminology:The term "muzzle", used as a noun, can be ambiguous...
is relatively large. The foregut
Foregut
The foregut is the anterior part of the alimentary canal, from the mouth to the duodenum at the entrance of the bile duct. At this point it is continuous with the midgut...
(of the digestive system
Digestive system of gastropods
The digestive system of gastropods has evolved to suit almost every kind of diet and feeding behavior. Gastropods as the largest taxonomic class of the mollusca are very diverse indeed: the group includes carnivores, herbivores, scavengers, filter feeders, and even parasites.In particular, the...
) is different from other families within the Muricoidea. The proboscis
Proboscis
A proboscis is an elongated appendage from the head of an animal, either a vertebrate or an invertebrate. In simpler terms, a proboscis is the straw-like mouth found in several varieties of species.-Etymology:...
is introvert, with a proboscis bulb that has an extreme thick wall. The proboscis bulb is connected directly to the buccal mass. There is no epiproboscis.
Species
Species within the genus Pleioptygma include:- † Pleioptygma brandyceae Petuch, 1994 - photo of the holotype
- † Pleioptygma carolinensePleioptygma carolinensePleioptygma carolinense is an extinct species of sea snail, a marine gastropod mollusk in the family Pleioptygmatidae.Pleioptygma carolinensis is the type species of the genus Pleioptygma.-Distribution :...
(Conrad, 1840) - type species, from PliocenePlioceneThe Pliocene Epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch...
. The type species is extinct. - † Pleioptygma debrae Petuch, 1994 - photo of the holotype
- † Pleioptygma heilprini Cossmann, 1899 http://paleodb.geology.wisc.edu/cgi-bin/bridge.pl?a=basicTaxonInfo&taxon_no=120367
- Pleioptygma helenaePleioptygma helenaePleioptygma helenae is a species of sea snail, a marine gastropod mollusk in the family Pleioptygmatidae.It is the only known living species in this genus and the only extant species in the family Pleioptygmatidae.-Distribution:Honduras....
(Radwin & Bibbey, 1972) - It is the only known living species in this genus. - † Pleioptygma kissimmeensis Petuch, 1994 - photo of the holotype
- † Pleioptygma limonensis Olsson, 1922 http://paleodb.geology.wisc.edu/cgi-bin/bridge.pl?a=basicTaxonInfo&taxon_no=164631
- † Pleioptygma lindae Petuch, 1991
- † Pleioptygma lineolatum lineolatum (Helprin, 1887)
- † Pleioptygma lineolatum saginatum (Tucker & Wilson, 1933)
- † Pleioptygma nancyae Petuch, 1994 - photo of the holotype
- † Pleioptygma prodroma (Gardner, 1937)
- † Pleioptygma ronaldsmithi Petuch, 1994 - photo of the holotype
- † Pleioptygma swainsonii Broderip, 1836 http://paleodb.geology.wisc.edu/cgi-bin/bridge.pl?a=basicTaxonInfo&taxon_no=164629
- † Pleioptygma zaca Strong et al., 1933http://paleodb.geology.wisc.edu/cgi-bin/bridge.pl?a=basicTaxonInfo&taxon_no=164639