Annulariidae


The family Annulariidae is a taxonomic family of small operculate land snails in the superfamily Littorinoidea.

Characteristics

This family encompasses all New World "Cyclostomoid" mollusks previously classified under the family names Cyclostomatidae or Eriidae.
Key Distinguishing Characteristics:
The primary feature that separates this family from all other operculate pulmonates is found in the radula, which exhibits a fundamental uniformity across the large number of included species.
;Radula Structure : the radula possesses a consistent tooth arrangement:
  • Rachidian tooth: single and unicuspid.
  • Lateral tooth: single and unicuspid.
  • Inner marginal tooth: resembles the lateral tooth in form but is multicuspid.
  • Outer Mmrginal tooth: long and curved like a bow. It is pectinated on both its recurved edge and its main portion, but these pectinations do not divide it into individual teeth.
  • Jaw: absent.
; Foot and progression: The sole of the foot is longitudinally divided by a sulcus, which separates it into two muscular masses. These two masses function independently, allowing the animal a method of progression by alternate waves of muscular contraction. The foot is relatively short.
; Head and sensory organs
  • Muzzle: a bifid muzzle of varying length is always present.
  • Tentacles: they are long, slender, and either fibrillar or slightly swollen at the ends.
  • Eyes: The eyes are situated at the base of the tentacles on the outer side. They are often raised above the surface of the head by a fleshy protuberance.
; Operculum: The operculum displays a wide degree of variation across the family's divisions, yet it follows distinct evolutionary lines of progression. The structure ranges from a simple type to a highly complicated one, with intermediate steps easily traceable. All opercula possess a basal chondroid plate upon which calcareous ribs and lamellae are deposited. Modifications of these calcareous structures are used to subdivide the family into a series of subfamilies and genera, as will be discussed below.
; Shell: The shell shape varies widely, from depressed helicoid to elongate conic. The surface sculpture varies greatly: from axially ribbed only to axially ribbed and spirally lirate. The intensity of these elements ranges from obsolete to lamellose.

Genera

;Subfamily Abbottellinae Watters, 2016
  • Abbottella Henderson & Bartsch, 1920
  • Abbottipoma Watters, M. L. Smith & Sneddon, 2020
  • Annularisca Henderson & Bartsch, 1920
  • Arenabbottella Watters, M. L. Smith & Sneddon, 2020
  • Lagopoma Bartsch, 1946
  • Leiabbottella Watters, 2010
  • Meganipha F. G. Thompson, 1978
  • Microabbottella Watters, M. L. Smith & Sneddon, 2020
  • Opisthosiphon Dall, 1905
  • Preclaripoma Watters, M. L. Smith & Sneddon, 2020
  • Rolleia Crosse, 1891
;Subfamily Annulariinae Henderson & Bartsch, 1920
  • Adamsiella L. Pfeiffer, 1851
  • Annularia Schumacher, 1817
  • Annularops Henderson & Bartsch, 1920
  • Blaesospira Crosse, 1891
  • Chittypoma Watters, 2006
  • Cistulops H. B. Baker, 1924
  • Eyerdamia Bartsch, 1946
  • Juannularia de la Torre & Bartsch, 1941
  • Lugarenia de la Torre & Bartsch, 1941
  • Megannularia Watters, 2006
  • Saulaepoma Watters, 2006
  • Weinlandipoma Bartsch, 1946
  • Xenopoma Crosse, 1891
  • Xenopomoides de la Torre & Bartsch, 1941
;Subfamily Chondropomatinae Henderson & Bartsch, 1920
  • Aguayotudora de la Torre & Bartsch, 1941
  • Annularodes Henderson & Bartsch, 1920
  • Bonairea H. B. Baker, 1924
  • Chondropoma L. Pfeiffer, 1847
  • Chondrops Bartsch, 1946
  • Chondrothyrium Henderson & Bartsch, 1920
  • Colonella Bartsch, 1946
  • Crossepoma Bartsch, 1946
  • Cubadamsiella de la Torre & Bartsch, 1941
  • Diplopoma L. Pfeiffer, 1859
  • Parachondria Dall, 1905
  • Parachondrops Henderson & Bartsch, 1920
  • Rhytidopoma Sykes, 1901
  • Rhytidothyra Henderson & Bartsch, 1920
;Subfamily Rhytidopomatinae Henderson & Bartsch, 1920
  • Colonina Bartsch, 1946
  • Ramsdenia Preston, 1913
;Subfamily Tudorinae Watters, 2006
  • Annularita Henderson & Bartsch, 1920
  • Articulipoma Bartsch, 1946
  • Choanopomops H. B. Baker, 1928
  • Chondropomartes Henderson & Bartsch, 1920
  • Chondropomella Bartsch, 1932
  • Chondropometes Henderson & Bartsch, 1920
  • Chondropomium Henderson & Bartsch, 1920
  • Chondrothyra Henderson & Bartsch, 1920
  • Clydonopoma Pilsbry, 1933
  • Colobostylus Crosse & P. Fischer, 1888
  • Dallsiphona de la Torre & Bartsch, 1941
  • Eutudora Henderson & Bartsch, 1920
  • Gouldipoma Watters, 2006
  • Gutierrezium de la Torre & Bartsch, 1938
  • Halotudora Watters, 2006
  • Licina Gray, 1847
  • Paradoxipoma Watters, 2014
  • Sallepoma Bartsch, 1946
  • Samanicola Watters, 2006
  • Superbipoma Watters & Larson, 2017
  • Tudora Gray, 1850
  • Tudorina de la Torre & Bartsch, 1941
  • Tudorisca Henderson & Bartsch, 1920
  • Turrithyra de la Torre & Bartsch, 1938
  • Tessaripoma Watters, 2016
  • Incertipoma Bartsch, 1946

    Distribution

Island of Hispaniola and the Bahama Archipelago.