Phylum: Bryozoa
Class: Stenolaemata
Order: Cystoporata
Genus: Ceramoporella Ulrich, 1882
Cincinnatian Species: Ceramoporella flabellata

[accordions title=”” disabled=”false” active=”1″ autoheight=”false” collapsible=”true”] [accordion title=”Taxonomic Details”]
Type Species: Ceramoporella distincta (Ulrich, 1882)
History (Nickles & Bassler, 1900):

    • 1882 Ceramoporella Ulrich, Jour. Cincinnati Soc. Nat. Hist., V, p. 156.
    • 1889 Ceramoporella Miller, North American Geol. Pal., p. 297.
    • 1890 Ceramoporella Ulrich, Geol. Surv. Illinois, VIII, pp.380, 464.
    • 1893 Ceramoporella Ulrich, Geol. Minnesota, III, p. 328.
    • 1896 Ceramoporella Ulrich, Zittel’s Textb. Pal. (Engl. ed.), p. 267.
    • 1897 Ceramoporella Simpson, Fourteenth Ann. Rep. State Geologist New York for the year 1894, p. 564.


  • Chiloporella Miller, 1889 (Type species: Fistulipora? flabellata Ulrich, 1879)
  • Cheiloporella Ulrich, 1882 (incorrect subsequent spelling)
  • Ceramporella Cummings & Galloway, 1913 (incorrect subsequent spelling)

Species found in the Cincinnatian, USA

  • Ceramoporella flabellata (Ulrich, 1879)
  • Ceramoporella milfordensis (James, 1878)
  • Ceramoporella nicholsoni (James, 1875)
  • Ceramoporella ohioensis (Nicholson, 1875)
  • Ceramoporella tubulosa (Cumings & Galloway, 1913)
  • Ceramoporella whitei (James, 1875)

[/accordion] [/accordions]

Geologic Range
Middle Ordovician (Mohawkian) – Upper Ordovician (Richmondian)

Stratigraphic Occurrences


Geographic Occurrences

[accordions title=”” disabled=”false” active=”1″ autoheight=”false” collapsible=”true”] [accordion title=”Stratigraphic Description”]
Sequences (Formations)

  • C6 Sequence (Elkhorn)
  • C5 Sequence (Whitewater, Liberty, Waynesville)
  • C4 Sequence (Arnheim)
  • C3 Sequence (Mount Auburn, Corryville)
  • C2 Sequence (Bellevue, Fairview) [/accordion] [/accordions]

Identification in Hand Sample:

  • Zoarium Morphology: Incrusting layers (Parasitic sheets) ; Superimposed layers may form masses
  • Zooecia: Thickened walls, oval apertures
  • Mesozooids: Numerous, often more or less isolating the zooecia
  • Monticules: Rounded monticules sometimes present
  • Maculae: N/A

[accordions title=”” disabled=”false” active=”1″ autoheight=”false” collapsible=”true”] [accordion title=”Published Description”]

Treatise on Invertebrate Paleontology Part G (1983):

  • Zoarium incrusting or frondescent. Monticules circular to elongate. Autozooecial cross-sectional area reduced from outer endozone to exozone, particularly in frondose zoaria. Autozooecia moderately small in exozone, cavity ovate to subcircular. Zooecial lining local. Communication pores rare. Lunaria increasing in size distally in endozone; nearly as large at zooecial bends as at zoarial surface; ends locally projecting into cavity; cores commonly one, rarely more, per lunarium; thin laminated layer locally on distal side. Commonly one, rarely more, convex or planar diaphragms of dense, light colored calcite per autozooecium. Most diaphragms abutting wall or curving proximally along wall; a few curving distally along wall. Diaphragms commonly at same level in adjacent zooecia. Exilazooecia partially to completely isolating zooecia; large and subangular in cross section in inner exozone, smaller and more circular distally. Lining commonly lacking. Diaphragms few, similar to zooecial diaphragms. Monticular exilazooecia, commonly of serial origin, clustering on semiprostrate proximal wall of autozooecium, is consistent with the emended definition of Ceramoporella. C. flabellata may have a frondose as well as an incrusting growth habit. Frondose zoaria commonly have longer and larger autozooecia in the endozone than do incrusting zoaria. Some zoaria of C. flabellata have thicker walls and autozooecial linings than do those of C. distincta and display only slight or partial radial arrangement of lunaria around the monticules.

McFarlan (1931):

  • Ceramoporella: Zooarium of incrusting layers, which by superposition may form masses; zooecia short, tubular with thin walls; apertures oval, oblique, the lunarium forming a hood; mesopores abundant, often completely encircling the zooecia.”

Bassler (1911):

  • Zoarium of incrusting layers, which by superposition may form masses; zooecia short, tubular with thin walls; apertures oval, oblique, the lunarium forming a hood; mesopores abundant, often completely encircling the zooecia.
  • Genotype.—Ceramoporella distincta Ulrich. Upper Ordovician (Eden and Maysville) of the Ohio Valley.
  • Until recently this genus has included all of the parasitic Ordovician ceramoporoids, but the discovery of the foregoing Russian species of incrusting, although otherwise typical Ceramopora in Ordovician strata, causes this conception to be modified. Ceramoporella includes two well-marked sections or groups of species, one in which the zooecia are inclined to be rhomboidal or polygonal in outline and more or less in contact, and another with rounded or ovate apertures and numerous mesopores. One or more distinct species of each section usually occur in each of the Ordovician formations, while a few species are of such generalized types of structure that they range through several formations and can be distinguished at best only as varieties. The new variety following belongs to the latter category.

Nickles & Bassler (1900):

  • Chiloporella: Zoarium forming parasitic sheets, from which rise flabellate fronds or compressed branches; zooecial tubes long, thin-walled, irregular in shape in immature region, near the surface walls, much thickened, diaphragms rarely developed; apertures ovate, lunarium conspicuously elevated; mesopores numerous

[/accordion] [/accordions]

C. flabellata