Orthoceratidae

Reconstruction of Michelinoceras by S. V. Naugol'nyh.

Belongs within: Michelinoceratida.
Contains: Orthoceras.

The Orthoceratidae includes orthocerid cephalopods from the Lower Ordovician to Upper Triassic; however, it is mostly defined by negative characteristics and its monophyly is potentially suspect. Some orthoceratids reached very large sizes.

Characters (from Sweet 1964): Smooth or elaborately ornamented conchs, generally subcircular in cross-section; central or subcentral siphuncle generally lacking endosiphuncular deposits.

<==Orthoceratidae [Orthocerotidae]
    |--Orthoceratinae S64
    |    |--Orthoceras S64
    |    |--Bifoveoceras Balashov 1956 S64
    |    |    `--*B. bifoveatum (Noetling 1884) [=Orthoceras bifoveatum] S64
    |    `--Ctenoceras Noetling 1884 [incl. Palaeocycloceras Shimizu & Obata 1936] S64
    |         `--*C. schmidtii Noetling 1884 S64
    |--Leurocycloceratinae S64
    |    |--Anaspyroceras Shimizu & Obata 1935 S64
    |    |    `--*A. anellus (Conrad 1843) [=Orthoceras anellus] S64
    |    |--Bohemites Zhuravleva 1962 S64
    |    |    `--*B. aculeatum (Barrande 1877) [=Orthoceras aculeatum] S64
    |    |--Metaspyroceras Foerste 1932 (see below for synonymy) S64
    |    |    `--*M. ruedemanni (Foerste 1928) [=Spyroceras ruedemanni] S64
    |    `--Leurocycloceras Foerste 1928 S64
    |         |--*L. raymondi Foerste 1928 S64
    |         |--L. brucense S64
    |         |--L. niagarense P68
    |         `--L. subannulare T64
    |--Kionoceratinae [Ohioceratidae] S64
    |    |--Ohioceras Shimizu & Obata 1935 S64
    |    |    `--*O. myrice (Hall & Whitfield 1875) [=Cyrtoceras myrice] S64
    |    |--Parakionoceras Foerste 1928 S64
    |    |    `--*P. originale (Barrande 1868) [=Orthoceras originale] S64
    |    |--Polygrammoceras Foerste in Twenhofel 1928 S64
    |    |    `--*P. twenhofeli Foerste in Twenhofel 1928 S64
    |    |--Thoracoceras Fischer de Waldheim 1844 (see below for synonymy) S64
    |    |    `--*T. vestitum Fischer de Waldheim 1844 S64
    |    `--Kionoceras Hyatt 1884 S64
    |         |--*K. doricum (Barrande 1868) [=Orthoceras doricum] S64
    |         |--K. angulatum T64
    |         |--K. austini Foerste 1928 P68
    |         |--K. barbense Foerste 1936 P68
    |         |--K. fililineatum Foerste 1928 P68
    |         |--K. hyatti T64
    |         |--K. orus [=Orthoceras (Kionoceras) orus] P68
    |         |--K. paucicostatum P68
    |         |--K. scalariforme P68
    |         `--K. strix P68
    `--Michelinoceratinae [Michelinoceratidae, Michelinocerotidae, Sinoceratidae] S64
         |--Arkonoceras Flower 1945 S64
         |    `--*A. arkonense (Whiteaves 1898) [=Orthoceras arkonense] S64
         |--Balticoceras Teichert 1940 S64
         |    `--*B. discors (Eichwald 1857) [=Trematoceras discors] S64
         |--Eotripteroceras Flower 1943 S64
         |    `--*E. minutum Flower 1943 S64
         |--Hesperoceras Miller & Youngquist 1947 S64
         |    `--*H. laudoni Miller & Youngquist 1947 S64
         |--Sinoceras Shimizu & Obata 1935 S64
         |    `--*S. chinense (Foord 1888) [=Orthoceras chinense] S64
         |--Plagiostomoceras Teichert & Glenister 1952 S64
         |    |--*P. pleurotomum (Barrande 1866) [=Orthoceras pleurotomum] S64
         |    `--P. panderi T64
         |--Pleurorthoceras Flower 1962 (see below for synonymy) S64
         |    |--*P. clarkesvillense (Foerste 1924) [=Orthoceras clarkesvillense] S64
         |    `--‘Orthoceras’ selkirkense Whiteaves 1892 [=*Foersteoceras selkirkense, *Shimizuoceras selkirkense] S64
         |--Trematoceras Eichwald 1851 S64
         |    |--*T. elegans (Münster 1841) [=Orthoceratites elegans] S64
         |    `--T. politum S64
         |--Bitaunioceras Shimizu & Obata 1936 S64
         |    |--*B. bitauniense (Haniel 1915) [=Orthoceras bitauniense] S64
         |    |--B. coahuilense S64
         |    `--B. texanum Miller & Youngquist 1947 P68
         `--Michelinoceras Foerste 1932 S64
              |--*M. michelini (Barrande 1866) [=Orthoceras michelini] S64
              |--M. anguliferum T64
              |    |--M. a. anguliferum T64
              |    `--M. a. alpenense T64
              |--M. dunbari T64
              |--M. dutroi Gordon 1957 P68
              `--M. niagarense H87

Metaspyroceras Foerste 1932 [incl. Eospyroceras Shimizu & Obata 1935, Hypospyroceras Shimizu & Obata 1935] S64

Pleurorthoceras Flower 1962 [incl. Foersteoceras Shimizu & Obata 1936 non Ruedemann 1925, Shimizuoceras Zhuravleva 1962] S64

Thoracoceras Fischer de Waldheim 1844 [=Melia Fischer de Waldheim 1829 (preoc.), Mellia (l. c.) nec Schmidt 1920 nec Meyrick 1934, Thoracocerus (l. c.)] S64

*Type species of generic name indicated

REFERENCES

[H87] Holland, C. H. 1987. The nautiloid cephalopods: a strange success story. Journal of the Geological Society 144 (1): 1-15.

[P68] Purnell, L. R. 1968. Catalog of the Type Specimens of Invertebrate Fossils. Part I: Paleozoic Cephalopoda. United States National Museum Bulletin 262: 1-198.

[S64] Sweet, W. C. 1964. Nautiloidea – Orthocerida. In Treatise on Invertebrate Paleontology pt. K. Mollusca 3. Cephalopoda – General Features – Endoceratoidea – Actinoceratoidea – Nautiloidea – Bactritoidea (R. C. Moore, ed.) pp. K216-K261. The Geological Society of America and the University of Kansas Press.

[T64] Teichert, C. 1964. Morphology of hard parts. In Treatise on Invertebrate Paleontology pt. K. Mollusca 3. Cephalopoda – General Features – Endoceratoidea – Actinoceratoidea – Nautiloidea – Bactritoidea (R. C. Moore, ed.) pp. K13-K53. The Geological Society of America and the University of Kansas Press.