Zyzzyxdonta alata
Encyclopedia
Zyzzyxdonta alata is a species
of air-breathing land snail
, a terrestrial
pulmonate gastropod mollusk in the family
Endodontidae
.
This is the only species
in the genus
Zyzzyxdonta. The genus was named Zyzzyxdonta because it has many features that are the opposite to the genus Aaadonta
. The name, given to the snail by malacologist Alan Solem
, is the last word in many species dictionaries, just after Zyzzyx
; however, they both, in fact, precede Zyzzyzus
.
They live in the Pacific islands of Palau
and Fiji
.
of Zyzzyxdonta alata has apical sculpture typical of the Endodontidae
. The postnuclear whorls have widely spaced radial ribs which protrude into hollow, winglike structures at the carinated periphery.
There are about 5 whorls
that are rather loosely coiled. The apex
is flat, but the spire
is slightly elevated.
The body whorl
has a protruded, keeled periphery, not descending more rapidly, with a distinct subperipheral sulcus. The umbilicus
is widely open and U-shaped. The last whorl does not decoil as rapidly. The apertural
barriers consist of three parietals, a single columellar one that slants downwards, and three long palatals. All barriers have large, swollen and serrated beads above them.
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 air-breathing land snail
Snail
Snail is a common name applied to most of the members of the molluscan class Gastropoda that have coiled shells in the adult stage. When the word is used in its most general sense, it includes sea snails, land snails and freshwater snails. The word snail without any qualifier is however more often...
, a terrestrial
Terrestrial animal
Terrestrial animals are animals that live predominantly or entirely on land , as compared with aquatic animals, which live predominantly or entirely in the water , or amphibians, which rely on a combination of aquatic and terrestrial habitats...
pulmonate gastropod mollusk in the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Endodontidae
Endodontidae
Endodontidae is a taxonomic family of very small air-breathing land snails and slugs, terrestrial pulmonate gastropod mollusks in the superfamily Punctoidea....
.
This is the only 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...
in the genus
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...
Zyzzyxdonta. The genus was named Zyzzyxdonta because it has many features that are the opposite to the genus Aaadonta
Aaadonta
Aaadonta is a genus of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Endodontidae. Specimens from this genus have been found in Palau and America.- Species :Species in the genus Aaadonta include:...
. The name, given to the snail by malacologist Alan Solem
Alan Solem
Alan Solem, full name George Alan Solem was an American malacologist, a biologist who studied mollusks.He was one of the most renown land snail experts of his time and had earned a reputation for his comprehensive revisions of mainly terrestrial pulmonates...
, is the last word in many species dictionaries, just after Zyzzyx
Zyzzyx
Zyzzyx is a monospecific genus of sand wasp, containing a brightly colored, medium-sized species, Z. chilensis. It is primarily a predator on flies, but has been observed to consume skippers. "Zyzzyx" is a replacement name proposed in 1937 by V. S. L. Pate for Therapon, originally described by J....
; however, they both, in fact, precede Zyzzyzus
Zyzzyzus
Zyzzyzus is a small genus of marine tubulariid hydrozoans.-Species:*Zyzzyzus floridanus Petersen, 1990*Zyzzyzus robustus Petersen, 1990*Zyzzyzus spongicolus *Zyzzyzus warreni Calder, 1988...
.
They live in the Pacific islands of Palau
Palau
Palau , officially the Republic of Palau , is an island nation in the Pacific Ocean, east of the Philippines and south of Tokyo. In 1978, after three decades as being part of the United Nations trusteeship, Palau chose independence instead of becoming part of the Federated States of Micronesia, a...
and Fiji
Fiji
Fiji , officially the Republic of Fiji , is an island nation in Melanesia in the South Pacific Ocean about northeast of New Zealand's North Island...
.
Description
The shellGastropod 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...
of Zyzzyxdonta alata has apical sculpture typical of the Endodontidae
Endodontidae
Endodontidae is a taxonomic family of very small air-breathing land snails and slugs, terrestrial pulmonate gastropod mollusks in the superfamily Punctoidea....
. The postnuclear whorls have widely spaced radial ribs which protrude into hollow, winglike structures at the carinated periphery.
There are about 5 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 rather loosely coiled. The apex
Apex (mollusc)
Apex is an anatomical term for the tip of the mollusc shell of a gastropod, scaphopod, or cephalopod mollusc.-Gastropods:The word "apex" is most often used to mean the tip of the spire of the shell of a gastropod...
is flat, but the spire
Spire (mollusc)
A spire is a descriptive term for part of the coiled shell of mollusks. The word is a convenient aid in describing shells, but it does not refer to a very precise part of shell anatomy: the spire consists of all of the whorls except for the body whorl...
is slightly elevated.
The body whorl
Body whorl
Body whorl is part of the morphology of a coiled gastropod mollusk.- In gastropods :In gastropods, the body whorl, or last whorl, is the most recently-formed and largest whorl of a spiral or helical shell, terminating in the aperture...
has a protruded, keeled periphery, not descending more rapidly, with a distinct subperipheral sulcus. The umbilicus
Umbilicus (mollusk)
The umbilicus of a shell is the axially aligned, hollow cone-shaped space within the whorls of a coiled mollusc shell. The term umbilicus is often used in descriptions of gastropod shells, i.e...
is widely open and U-shaped. The last whorl does not decoil as rapidly. The apertural
Aperture (mollusc)
The aperture is an opening in certain kinds of mollusc shells: it is the main opening of the shell, where part of the body of the animal emerges for locomotion, feeding, etc....
barriers consist of three parietals, a single columellar one that slants downwards, and three long palatals. All barriers have large, swollen and serrated beads above them.