Khairkhaniidae

The Lower Devonian onychochilid Voskopiella barborae, from Frýda (1992).

Belongs within: Mollusca.

The Khairkhaniidae were a Lower Cambrian family of planispiral molluscs, possibly basal or stem gastropods. Parkhaev (2002) suggested that the khairkhaniid genus Protowenella was ancestral to the Upper Cambrian to Lower Devonian Onychochilidae, a family of turbospiral hyperstrophic forms, though he did not explicitly state his reasons for suggesting the connection.

Characters of Khairkhaniidae (from Parkhaev 2002): Shell planispiral or almost planispiral with up to three or four coils. Aperture almost circular with diameter significantly less than diameter of shell (Parkhaev's listing of a paired pallial caecum as a character of Khairkhaniidae should be treated with caution, as this is not something that can be observed directly from the shell).

<==Khairkhaniidae [Khairkhaniiformes]
    |--+--+--Barskovia Golubev 1976 [incl. Nekolenia Vassiljeva 1998] P02
    |  |  `--Philoxenella Vostokova 1962 P02
    |  `--+--Khairkhania Missarzhevsky 1981 P02
    |     |--Ardrossania Runnegar in Bengtson et al. 1990 P02
    |     `--Michniakia Missarzhevsky 1966 P02
    `--+--Protowenella Runnegar & Jell 1976 P02
       `--+--Xinjispira Yu & Rong 1987 P02
          `--Clisospiroidea (see below for synonymy) BR05
               |  i. s.: Mimospira FB01
               |--Clisospiridae BR05
               |    |--Atracura Horný 1964 [Atracurinae] BR05
               |    |--Trochoclisa Horný 1964 [Trochoclisinae] BR05
               |    `--Clisospirinae BR05
               |         |--Clisospira Billings 1865 BR05
               |         `--Progalerus Holzapfel 1895 [Progalerinae] BR05
               `--Onychochilidae P02
                    |--Beshtashella Missarzhevsky in Missarzhevsky & Mambetov 1981 P02
                    |--Voskopiella barborae Frýda 1992 FBL02
                    |--Onychochilus Lindström 1884 [Onychochilinae] BR05
                    |--Hyperstrophema Horný 1964 [Hyperstropheminae] BR05
                    |--Scaevogyra Whitfield 1878 [Scaevogyridae, Scaevogyrinae] BR05
                    `--Yuwenia Runnegar 1981 [incl. Kistassella Missarzhevsky 1989] P02
                         `--*Y. bentleyi Runnegar 1981 [incl. *Kistassella spiralis Missarzhevsky 1989] P02

Clisospiroidea [Clisospiracea, Dextrobranchia, Mimospirina, Onychochiliformes, Onychochiloidea, Umbraculiformii] BR05

*Type species of generic name indicated

REFERENCES

[BR05] Bouchet, P., J.-P. Rocroi, J. Frýda, B. Hausdorf, W. Ponder, Á. Valdés & A. Warén. 2005. Classification and nomenclator of gastropod families. Malacologia 47 (1-2): 1-397.

Frýda, J. 1992. Mode of life of a new onychochilid mollusc from the Lower Devonian of Bohemia. Journal of Paleontology 66 (2): 200-205.

[FB01] Frýda, J., & R. B. Blodgett. 2001. The oldest known heterobranch gastropod, Kuskokwimia gen. nov., from the Early Devonian of west-central Alaska, with notes on the early phylogeny of higher gastropods. Vĕstnik Českého Geologického Ústavu 76 (1): 39-53.

[FBL02] Frýda, J., R. B. Blodgett & A. C. Lenz. 2002. New Early Devonian gastropods from the families Crassimarginatidae (new family) and Scoliostomatidae (new family), Royal Creek area, Yukon Territory, Canada. Journal of Paleontology 76 (2): 246-255.

[P02] Parkhaev, P. Yu. 2002. Phylogenesis and the system of the Cambrian univalved mollusks. Paleontologicheskii Zhurnal 2002 (1): 27-39 (transl. Paleontological Journal 36 (1): 25-36).