Cornulitidae

Ontogeny of Cornulites, from Fisher (1962).


Belongs within: Animalia.

The Cornulitidae are a group of tubular, annular fossils of uncertain affinities known from the Middle Ordovician to the Lower Carboniferous (Fisher 1962).

Characters (from Fisher 1962): Flexuous, ringed, small to medium-sized tapering tubers of calcium carbonate, with circular cross section; rings dominant in specific stages of growth, longitudinal striae dominant in other stages. Relatively thick walls composed of large, rounded or oval cellular cavities, cells with thin walls and especially conspicuous in transverse rings which are narrower and closer together toward apex. Mould of internal cavity consisting of rodlike tapering body of invaginated cones with apices directed toward aperture. Length 5–80 mm; diameter 2–20 mm at aperture.

<==Cornulitidae F62
    |--Conchicolites Nicholson 1872 F62
    |    `--*C. gregarius Nicholson 1872 F62
    |--Cornulitella Howell 1952 [=Ortonia Nicholson 1872 non Wood 1869] F62
    |    `--*C. conica (Nicholson 1872) [=*Ortonia conica] F62
    |--Kolihaia Prantl 1944 F62
    |    `--*K. eremita Prantl 1944 F62
    `--Cornulites Schlotheim 1820 F62
         |--*C. serpularius Schlotheim 1820 F62
         |--C. sterlingensis F62
         `--C. tasmanicus Etheridge 1895-1896 F71

*Type species of generic name indicated

REFERENCES

[F62] Fisher, D. W. 1962. Small conoidal shells of uncertain affinities. In: Moore, R. C. (ed.) Treatise on Invertebrate Paleontology pt W. Miscellanea: Conodonts, Conoidal Shells of Uncertain Affinities, Worms, Trace Fossils and Problematica pp. W98–W143. Geological Society of America, and University of Kansas Press.

[F71] Fletcher, H. O. 1971. Catalogue of type specimens of fossils in the Australian Museum, Sydney. Australian Museum Memoir 13: 1–167.

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