Strobilopsidae | |
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Engraving showing an apertural view of a shell of Strobilops labyrinthicus | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Gastropoda |
Subclass: | Heterobranchia |
Order: | Stylommatophora |
Suborder: | Helicina |
Infraorder: | Pupilloidei |
Superfamily: | Pupilloidea |
Family: | Strobilopsidae Wenz, 1915 |
Genera | |
See text | |
Synonyms | |
Strobilidae Jooss, 1914 (inv.) |
Strobilopsidae is a family of air-breathing land snails, terrestrial pulmonate gastropod molluscs in the superfamily Pupilloidea.
The family Strobilopsidae is classified within the informal group Orthurethra, itself belonging to the clade Stylommatophora within the clade Eupulmonata (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005). [1]
The family Strobilopsidae has no subfamilies according to the taxonomy of the Gastropoda by Bouchet & Rocroi (2005).
Some authorities place the family Spelaeodiscidae as a subfamily (Spelaeodiscinae) of the Strobilopsidae. [2] [3]
Genera within the family Strobilopsidae include:
The shell is trochiform, dome-shaped or discoidal and umbilicate. The shell has from four to six slowly enlarging whorls. The aperture is small, oblique, with armature of two or three parietal lamellae and several deeply placed basal folds, all growing continuously from an early neanic stage. The peristome is more or less thickened and expanded, the ends of the lip remote, joined by a parietal callus. [5]
The shell, aside from its helicoid shape (not a character of great importance), differs from all Pupillidae in the arrangement of the lamellae and baso-palatal folds. In multidentate Pupillidae the five primary teeth are always recognizable while in Strobilops only the main parietal lamella and the columellar lamella can certainly be said to correspond, and these are found in so many other land shells that their occurrence is not especially significant. It is possible that upper and lower palatal folds of Pupillidae are represented by teeth 5 (the most right basal tooth) and 2 (second left basal tooth), and the basal fold by tooth 1 (the most left basal tooth). [5]
By the accelerated lamellae and folds of the shell, which appear early in the neanic stage, Strobilops resembles various Tornatellininae (within Achatinellidae). In that family both parietal and palatal folds or laminae are sometimes present in the neanic stage. Various pupillid genera also, such as Orcula (Orculidae) and Lauria (Lauriidae), have apertural armature during the neanic stage. Orcula has spiral parietal and columellar lamellae but no basal or palatal folds. Lauria has basal folds, but they are spaced, transverse barriers, wholly unlike the adult basal or palatal armature of the species, and differing equally from the folds of immature Strobilops, which from their inception appear to develop continuously into those of the adult shell. It appears likely that the acceleration or early appearance of apertural armature in Tornatellininae, Orcula, Lauria and Strobilops has been independent in the four groups, and is not indicative of direct relationship between any of them. [5]
The urethra lies very near the last part of the intestine. [5]
Digestive system: The jaw has numerous ribs. Radula with tricuspid central tooth with square basal plate, as large as the bicuspid laterals, the marginals multicuspid. [5]
Reproductive system: Ovotestis forms two groups of follicles. Penis is continued in a long epiphallus and bears a long appendix, with swollen basal and distal divisions, the penial retractor bifurcate, one branch inserted on the epiphallus, the other on the base of the appendix (distally it attaches to the right ocular retractor, according to G. Dallas Hanna). [5]
By the structure of the male organs Strobilops resembles Vallonia , Pupilla , Lauria , the Achatinellidae, and some other groups are similar in having a bifurcate penial retractor and a long, tripartite appendix. If G. Dallas Hanna is right in stating that the penial retractor is a branch of the right ocular band, this is an important difference from any known Orthurethra. The mouth parts do not differ materially from some Pupillidae. [5]
Strobilopsidae appeared in the Upper Eocene of western Europe in several species having all the external characters of the genus Strobilops, and though the internal structure has not been worked out (in 1927), [5] it is safe to assume that they are closely related to the well-known Oligocene forms following them. In Europe this genus continued in numerous species into the Pliocene, the last one in the Upper Pliocene (Astian stage) of Piedmont. [5]
In late Cretaceous beds there are various forms described as Helix, or under the names Obbinula and Pseudostrobilus , which certainly have some of the characters of Strobilops. All are larger than any Strobilops. [5]
Pulmonata or pulmonates is an informal group of snails and slugs characterized by the ability to breathe air, by virtue of having a pallial lung instead of a gill, or gills. The group includes many land and freshwater families, and several marine families.
The aperture is an opening in certain kinds of mollusc shells: it is the main opening of the shell, where the head-foot part of the body of the animal emerges for locomotion, feeding, etc.
Stylommatophora is an order of air-breathing land snails and slugs, terrestrial pulmonate gastropod molluscs. This taxon includes most land snails and slugs. Stylommatophorans lack an operculum, but some close their shell apertures with temporary "operculum" (epiphragm) made of calcified mucus. They have two pairs of retractile tentacles, the upper pair of which bears eyes on the tentacle tips. All stylommatophorans are hermaphrodites.
Vertigo dedecora is a species of very small air-breathing land snail, a terrestrial pulmonate gastropod mollusk or micromollusk in the family Vertiginidae.
The Alabama vertigo is a species of land snail in the family Vertiginidae, the whorl snails.
Vertigo pygmaea, common name the "crested vertigo", is a species of minute air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Vertiginidae, the whorl snails.
Vertigo ronnebyensis is a species of minute air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Vertiginidae, the whorl snails.
Vertigo antivertigo is a species of minute air-breathing land snail, a terrestrial pulmonate gastropod mollusc or micromollusc in the family Vertiginidae, the whorl snails.
Anostoma, common name the up-mouth snails, is a genus of tropical air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Odontostomidae. Snails in this genus are found in Brazil.
Anostoma octodentatum, common name Brazilian up-mouth snail, is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Odontostomidae.
Anostoma depressum is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusc in the family Odontostomidae.
Ringicella ringens is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Odontostomidae.
Orthurethra is a clade of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the clade Stylommatophora.
Pupilloidea is a superfamily of small and very small air-breathing land snails, terrestrial gastropod mollusks in the infraorder Pupilloidei.
Plectopyloidea is a taxonomic superfamily of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the suborder Helicina.
Eostrobilops hirasei is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Strobilopsidae.
Atractophaedusa smithi is a species of air-breathing land snail, a terrestrial gastropod mollusk in the family Clausiliidae, the door snails.
Spelaeoconcha paganettii is a species of very small air-breathing land snail, terrestrial pulmonate gastropod mollusks in the superfamily Pupilloidea.
Odontostomidae is a taxonomic family of medium-sized to large, air-breathing, tropical and sub-tropical land snails, terrestrial pulmonate gastropod molluscs in the superfamily Orthalicoidea.
Perrottetia aquilonaris is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusc in the family Streptaxidae.
This article incorporates public domain text originating from the USA from the reference [5] (1927 work without copyright notice).