Specimen of Dawsonoceras annulatum, from here.

Belongs within: Cephalopoda.
Contains: Pseudorthoceratidae, Proteoceratidae, Troedssonellidae, Sactorthoceratidae, Orthoceratidae, Paraphragmitidae, Geisonoceratidae.

The Michelinoceratida or Orthocerida were a Lower Ordovician to Upper Triassic assemblage of orthoconic or cyrtoconic cephalopods. This is perhaps the most systematically difficult group of fossil cephalopods and may be polyphyletic, with recent authors suggesting that some families (particularly the Pseudorthoceratidae) should be removed from the order.

Characters (from Sweet 1964): Conchs straight to curved (never coiled), smooth or elaborately ornamented; cameral deposits typically well developed; siphuncles with orthochoanitic or secondarily cyrtochoanitic septal necks and thin connecting rings, empty or occupied by parietal or annulosiphonate deposits.

<==Michelinoceratida (see below for synonymy)
    |--Pseudorthocerataceae S64
    |    |--Pseudorthoceratidae S64
    |    |--Proteoceratidae S64
    |    |--Mysterioceras Teichert & Glenister 1953 [Mysterioceratidae] S64
    |    |    `--*M. australe Teichert & Glenister 1953 S64
    |    `--Stereoplasmoceras Grabau 1922 [incl. Stereoplasmocerina Kobayashi 1936; Stereoplasmoceratidae] S64
    |         |--*S. pseudoseptatum Grabau 1922 S64
    |         |--S. approximatum S64
    |         |--S. liaotungense D82
    |         |--S. longicameratum S64
    |         `--S. tofangoense S64
    `--Orthocerataceae [Orthocerocea, Orthocerotoidea] S64
         |  i. s.: Sphooceras Flower 1962 [Sphooceratidae] S64
         |           `--*S. truncatum (Barrande 1868) [=Orthoceras truncatum] S64
         |         Brachycycloceras Miller, Dunbar & Condra 1933 [Brachycycloceratidae] S64
         |           |--*B. normale Miller, Dunbar & Condra 1933 S64
         |           |--B. bransoni S64
         |           `--B. curtum S64
         |         Troedssonellidae S64
         |         Dawsonoceratidae S64
         |           |--Dawsonocerina HornĂ½ 1956 S64
         |           |    `--*D. omega (Barrande 1868) [=Orthoceras dulce var. omega] S64
         |           `--Dawsonoceras Hyatt 1884 [incl. Cedarvilleoceras Shimizu & Obata 1935] S64
         |                |--*D. annulatum (Sowerby 1818) [=Orthocera annulata] S64
         |                |--D. americanum P68
         |                |--D. hammelli (Foerste 1910) [=Orthoceras (Dawsonoceras) hammelli] P68
         |                |--D. nodocostatum P68
         |                `--D. perelegans [=Orthoceras (Dawsonoceras) perelegans] P68
         |         Offleyoceras Foerste 1928 [Offleyoceratidae] S64
         |           `--*O. arcticum (Foord 1888) [=Orthoceras arcticum] S64
         |--Sactorthoceratidae S64
         `--+--Orthoceratidae S64
            |--Paraphragmitidae S64
            |--Geisonoceratidae S64
            `--Lamellorthoceratidae S64
                 |--Gorgonoceras Zhuravleva 1961 S64
                 |    `--*G. visendum Zhuravleva 1961 S64
                 |--Lamellorthoceras Termier & Termier 1950 (see below for synonymy) S64
                 |    |--*L. vermiculare Termier & Termier 1950 S64
                 |    `--L. gracile S64
                 `--Arthrophyllum Beyrich 1850 S64
                      |--*A. crassum (Roemer 1843) [=Orthoceratites crassus] S64
                      `--A. kahlebergense S64

Michelinoceratida incertae sedis:
  Chicagooceras Foerste & Savage 1927 S64
    `--*C. welleri Foerste & Savage 1927 S64
  Cycloceras M’Coy 1844 [=Cycoceras (l. c.); incl. Perigrammoceras Foerste 1924; Cycloceratidae] S64
    |--*C. annulare (Fleming 1815) [=Orthocera annularis] S64
    |--C. amycus [=Orthoceras (Cycloceras) amycus] P68
    |--C. annulatum [=Orthoceras (Cycloceras) annulatum] P68
    |--C. aokii Endo 1932 P68
    |--C. austini Foerste 1928 P68
    |--C. ballianum Girty 1909 P68
    |--C. inceptum P68
    |--C. junciforme Foerste 1928 P68
    |--C. laevigatum (Foord 1897) [=Orthoceras laevigatum, *Perigrammoceras laevigatum] S64
    |--C. louderbacki Endo 1932 P68
    |--C. manchuriense Endo 1932 P68
    |--C. marginale Endo 1932 P68
    |--C. novacarlislensis (Foerste 1890) [=Orthoceras (Cycloceras) novacarlislensis] P68
    |--C. peitoutzense P68
    `--C. shensiense Endo 1932 P68
  Dictyoceras Eichwald 1860 S64
    `--*D. porosum (Eichwald 1857) [=Orthoceras porosum] S64
  Donacoceras Foerste 1925 S64
    `--*D. timiskamingense Foerste 1925 S64
  Garryoceras Foerste 1928 S64
    `--*G. semiplanatum (Whiteaves 1892) [=Orthoceras semiplanatum] S64
  Heloceras Eichwald 1860 S64
    `--*H. tuberculatum Eichwald 1860 S64
  Loxoceras M’Coy 1844 [=Breynioceras Foerste 1929; Loxoceratidae] S64
    |--*L. breyni (Fleming 1828) [=Orthocera breyni, *Breynioceras breyni] S64
    |--L. husseyi Foerste 1923 P68
    `--L. milleri (Foerste 1910) [=Orthoceras (Loxoceras) milleri] P68
  ‘Molossus’ deMontfort 1808 non Geoffroy 1805 S64
    `--*M. gracilis (Blumenbach 1803) [=Orthoceratites gracilis] S64
  Neorthoceras Shimizu & Obata 1936 S64
    `--*N. verbeeki (Haniel 1915) [=Orthoceras verbeeki] S64
  Protobactrites Hyatt in Zittel 1900 [=Protobactolites (l. c.)] S64
    `--*P. styloideum (Barrande 1866) [=Orthoceras styloideum] S64
  Sannionites Fischer de Waldheim 1829 S64
    `--*S. crepitaculum Fischer de Waldheim 1829 S64
  Subspyroceras Shimizu & Obata 1935 S64
    `--*S. middlevillense (Foerste 1928) [=Spyroceras middlevillense] S64
  Tienoceras Chao 1954 S64
    `--*T. lenticulare Chao 1954 S64
  Tretoceras Salter 1858 [=Diploceras Salter 1856 non Conrad 1842, Tritoceras (l. c.)] S64
    `--*T. bisiphonatum (Sowerby in Murchison 1839) (see below for synonymy) S64

Lamellorthoceras Termier & Termier 1950 [=Lamelloceras (l. c.); incl. Coralloceras Zhuravleva 1962] S64

Michelinoceratida [Michelinoceratina, Michelinoceroida, Orthoceracea, Orthoceratida, Orthocerida, Orthocerotida, Sinoceratida]

*Tretoceras bisiphonatum (Sowerby in Murchison 1839) [=Orthoceras bisiphonatum, *Diploceras bisiphonatum] S64

*Type species of generic name indicated


[D82] Dong D.-Y. 1982. Lower Ordovician stromatoporoids of northern Anhui. Acta Palaeontologica Sinica 21 (5): 577-583.

[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.

No comments:

Post a Comment

Markup Key:
- <b>bold</b> = bold
- <i>italic</i> = italic
- <a href="http://www.fieldofscience.com/">FoS</a> = FoS