Hemicosmitida

Theca of Hemicosmites extraneus, from here.

Belongs within: Dichoporita.

The Hemicosmitida are a group of Middle Ordovician to Lower Devonian cystoids, in which the pore rhombs have the pore openings covered by an external epitheca.

<==Hemicosmitida [Hemicosmites] K67
    |--Heterocystites Hall 1851 [=Heterocystis Bather 1900; Heterocystidae, Heterocystitidae] K67
    |    `--*H. armatus Hall 1851 [=*Heterocystis armata] K67
    |--Hemicosmitidae K67
    |    |--Tricosmites Jaekel 1918 K67
    |    |    `--*T. tricornis (Jaekel 1899) [=Hemicosmites tricornis] K67
    |    |--Corylocrinus Koenen 1886 [=Cordylocrinus (l. c.) non Angelin 1878] K67
    |    |    |--C. europaeus (Quenstedt 1874) [=Caryocrinus europaeus; incl. *Corylocrinus pyriformis Koenen 1886] K67
    |    |    |--C. carnicus K67
    |    |    |--C. elongatus K67
    |    |    |--C. occidentalis K67
    |    |    `--C. olli K67
    |    `--Hemicosmites von Buch 1840 [incl. Hexalacystis Haeckel 1896] K67
    |         |--*H. pyriformis von Buch 1840 K67
    |         |--H. altus Jaekel 1918 J18
    |         |--H. extraneus K67
    |         |--H. grandis K67
    |         |--H. jaekeli K67
    |         |--H. laevior K67
    |         |--H. malum K67
    |         |--H. oblongus K67
    |         |--H. oelandicus K67
    |         |--H. pocillus K67
    |         |--H. porosus K67
    |         |--H. pulcherrimus K67
    |         |--H. rudis K67
    |         |--H. squamosus K67
    |         `--H. verrucosus Eichwald 1856 [=*Hexalacystis verrucosa] K67
    `--Caryocrinitidae [Caryocrinidae] K67
         |--Juglandocrinus Koenen 1886 [=Inglandocrinus (l. c.)] K67
         |    `--*J. crassus Koenen 1886 K67
         |--Ptychocosmites Jaekel 1918 K67
         |    `--*P. sardinicus Jaekel 1918 K67
         |--Stribalocystites Miller 1891 [=Stribalocystis Bather 1900, Strybalocystis Rowley 1900] K67
         |    |--*S. tumida Miller 1891 [=*Stribalocystis tumida, *Strybalocystis tumida] K67
         |    |--S. bulbulus K67
         |    |--S. kentuckiensis K67
         |    `--S. sphaeroidalis K67
         |--Oocystis Dreyfuss 1939 K67
         |    |--*O. vulgaris Dreyfuss 1939 K67
         |    |    |--O. v. vulgaris K67
         |    |    `--O. v. subsphaeroidalis K67
         |    |--O. major K67
         |    `--O. rugata K67
         `--Caryocrinites Say 1825 (see below for synonymy) K67
              |--*C. ornatus Say 1825 [=*Cariocrinus ornatus, *Caryocrinus ornatus] K67
              |    |--C. o. ornatus K67
              |    `--C. o. europaeus K67
              |--C. aurorus K67
              |--C. avellanus K67
              |--‘*Enneacystis’ buchiana Haeckel 1896 K67
              |--C. globosus K67
              |--C. gorbyi K67
              |--C. indianensis K67
              |--C. milliganae K67
              |--C. missouriensis K67
              |--C. persculptus K67
              |--C. septentrionalis K67
              `--C. turbo K67

Caryocrinites Say 1825 [=Cariocrinites (l. c.), Cariocrinus Austin & Austin 1845, Caryocrinus Agassiz 1836; incl. Enneacystis Haeckel 1896] K67

*Type species of generic name indicated

REFERENCES

[J18] Jaekel, O. 1918. Phylogenie und System der Pelmatozoen. Paläontologische Zeitschrift 3: 1-128.

[K67] Kesling, R. V. 1967. Cystoids. In Treatise on Invertebrate Paleontology pt. S. Echinodermata 1. General characters. Homalozoa-Crinozoa (except Crinoidea) (R. C. Moore, ed.) vol. 1 pp. S85-S267. The Geological Society of America, Inc., and The University of Kansas: Lawrence (Kansas).