Staffordiidae
Encyclopedia
Staffordiidae is a 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...

 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...

s, 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 mollusks in the superfamily Staffordioidea (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005
Taxonomy of the Gastropoda (Bouchet & Rocroi, 2005)
The taxonomy of the Gastropoda as it was revised by Philippe Bouchet and Jean-Pierre Rocroi is currently the most up-to-date overall system for classifying gastropod mollusks...

).

Staffordiidae is the only family in the superamily Staffordioidea. This family has no subfamilies (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005
Taxonomy of the Gastropoda (Bouchet & Rocroi, 2005)
The taxonomy of the Gastropoda as it was revised by Philippe Bouchet and Jean-Pierre Rocroi is currently the most up-to-date overall system for classifying gastropod mollusks...

).

Staffordiidae is poorly known family, because it occur only in Dafla Hills area, India, that is very insufficiently known.

Various sources consider Staffordiidae as a part of Dyakiidae
Dyakiidae
Dyakiidae is a family of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the superfamily Dyakioidea ....

 or Ariophantidae
Ariophantidae
Ariophantidae is a taxonomic family of air-breathing land snails and semi-slugs, terrestrial pulmonate gastropod mollusks in the superfamily Helicarionoidea .- Distribution :...

/Dyakiinae.

Distribution

Distribution of Staffordiidae include only India in Dafla Hills.

This area is close to northern margin of Indian plate. The historical area of origin of Staffordiidae is not surely known, because the possible coastal area in southern Asia is considered to became uninhabitable after Indian Plate and Eurasian Plate
Eurasian Plate
The Eurasian Plate is a tectonic plate which includes most of the continent of Eurasia , with the notable exceptions of the Indian subcontinent, the Arabian subcontinent, and the area east of the Chersky Range in East Siberia...

 collision
Continental collision
Continental collision is a phenomenon of the plate tectonics of Earth that occurs at convergent boundaries. Continental collision is a variation on the fundamental process of subduction, whereby the subduction zone is destroyed, mountains produced, and two continents sutured together...

 50 and 55 million years ago. The original ancestral area of limacoid families is thought to be Palaearctic region and south-eastern Asia. So it has been hypothetized that Staffordiidae have colonized its actual area from southern margin of Asian part of Eurasian Plate in Oligocene
Oligocene
The Oligocene is a geologic epoch of the Paleogene Period and extends from about 34 million to 23 million years before the present . As with other older geologic periods, the rock beds that define the period are well identified but the exact dates of the start and end of the period are slightly...

.

Genera

Genera within the family Staffordiidae include:
  • Staffordia
    Staffordia
    Staffordia is a genus of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Staffordiidae.- Species :Species within the genus Staffordia include:* Staffordia daflaensis* Staffordia staffordi...

    Godwin-Austen, 1907 - type genus of the family
    • Staffordia daflaensis
      Staffordia daflaensis
      Staffordia daflaensis is a species of air-breathing land snail, terrestrial pulmonate gastropod mollusk in the family Staffordiidae.The specific name daflaensis is apparently according to its area of distribution, Dafla Hills in India....

      (Godwin-Austen)
    • Staffordia staffordi
      Staffordia staffordi
      Staffordia staffordi is a species of air-breathing land snail, terrestrial pulmonate gastropod mollusk in the family Staffordiidae.The specific name staffordi as well as generic name Staffordia is in honor of Brigadier-General Stafford, who was in command of the punitive force which entered the...

      Godwin-Austen, 1907
    • Staffordia toruputuensis
      Staffordia toruputuensis
      Staffordia toruputuensis is a species of air-breathing land snail, terrestrial pulmonate gastropod mollusk in the family Staffordiidae.The specific name toruputuensis is apparently according to its type locality, Toruputu Peak.- Distribution :...

      Godwin-Austen


The generic name Staffordia is in honor of Brigadier-General Stafford
Stafford (disambiguation)
-Other places in England:* Stafford * West Stafford, in Dorset-United States:*Stafford, California **Stafford, Humboldt County, California...

, who was in command of the punitive force which entered the Dafla Hills for the first time in the winter of 1874-1875.

The foot of Staffordia is pointed. The peripodial margin is simple with a narrow pale margin. There are present small right and left shell-lobes.

Reproductive system
Reproductive system of gastropods
The reproductive system of gastropods varies greatly from one group to another within this very large and diverse taxonomic class of animals...

 of Staffordia: the dart
Love dart
A love dart is a hard, long, sharp, calcareous or chitinous dart which some hermaphroditic land snails and slugs create. Love darts are made in sexually mature animals only, and are used as part of the sequence of events during courtship, before actual mating takes place...

-sac is small, globose, with a long cord-like attachment to a coronal gland. The penis is simple. The spermatheca is long.

Radula
Radula
The radula is an anatomical structure that is used by molluscs for feeding, sometimes compared rather inaccurately to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food enters the esophagus...

 of Staffordia is with aculeate laterals.

Comparison of shells of Staffordia species:

Cladogram

Staffordiidae is considered as sister group of all other families in the limacoid clade.

The following cladogram
Cladogram
A cladogram is a diagram used in cladistics which shows ancestral relations between organisms, to represent the evolutionary tree of life. Although traditionally such cladograms were generated largely on the basis of morphological characters, DNA and RNA sequencing data and computational...

 shows the phylogenic relationships of this family and superfamily to the other families within the limacoid clade
Limacoid clade
The limacoid clade is a taxonomic clade of air-breathing land snails, semislugs and slugs, terrestrial pulmonate gastropod molluscs in the informal group Sigmurethra.- Distribution :...

:

Further reading

  • Schileyko A. A. (2003). "Treatise on recent terrestrial pulmonate mollusks. 10. Ariophantidae, Ostracolethaidae, Ryssotidae, Milacidae, Dyakiidae, Staffordiidae, Gastrodontidae, Zonitidae, Daudebardiidae, Parmacellidae". Ruthenica, Supplement 2. 1309-1466.
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