Bryozoans appear in the fossil record in the Lower Ordovician but might be found in Late Cambrian. They are colonial animals, dominantly marine. (Freshwater species have an organic skeleton that doesn’t preserve in the fossil record.) Bryozoans are difficult to identify because the internal structure is used. However, some bryozoans have distinctive exterior features.

Septopora subquadrans Ulrich

Bryozoan Photos (more to be added)

Archimedes is the central axis of a fenestrate bryozoan. Specimens are often found in matrix.

Preservation: C = Calcified, Ph = Phosphatic, P = Pyritized, S =Silicified, 1= w/o, matrix, 2 = w/ matrix

# No specimens for sale

BRYOZOANS                                           Period                                           Location        Preservation

Amplexopora septosa                         Upper Ordovician                                KY                          C,1,2

Anastomopora adnata (Hall)? – 2.5 cm view

Anastomopora adnata (Hall)# – Jeffersonville Limestone, Middle Devonian, KY – C, 2

Archimedes communis                      Upper Mississippian                            KY                          C,1

Archimedes confertus Ulrich

Archimedes confertus  Ulrich – Glen Dean Fm., Upper Mississippian, KY – C,1,2

Archimedes distans Ulrich

Archimedes distans Ulrich – Glen Dean Fm., Upper Mississippian, KY – C,1,2

Archimedes intermedius Ulrich

Archimedes intermedius Ulrich – Glen Dean Fm., Upper Mississippian, KY – C,1,2

Archimedes invaginatus Ulrich

Archimedes invaginatus Ulrich – Glen Dean Fm., Upper Mississippian, KY – C,1,2

Archimedes laxus                                   ”             ”                                           KY                          C,1

Archimedes macfarlani                          ”             ”                                           KY                          C,1,2

Archimedes meekanoides McFarlan

Archimedes meekanoides McFarlan – Glen Dean Fm., Upper Mississippian, KY – C,1,2

Archimedes meekanus Hall

Archimedes meekanus Hall – Glen Dean Fm., Upper Mississippian, KY – C,1,2

Archimedes proutanus Ulrich

Archimedes proutanus Ulrich – Glen Dean Fm., Upper Mississippian, KY – C,1,2

Archimedes sp.                                        ”             ”                                         IN,AL                     C,1,2

Aspidopora newberryi (Nicholson) – about 5 mm wide

Aspidopora newberryi (Nicholson)# – a small encrusting species, Upper Ordovician, IN, KY – C1,2

Batostoma gracilis                               Upper Ordovician                                KY,IN                    C,1

Batostoma jamesi                                    ”             ”                                        KY                          C,1

Batostoma varians                                  ”             ”                                         KY,IN                    C,1

“Chaetetes” consimilis Hall

“Chaetetes” consimilis Hall# – current name unknown, flattened fronds. Waldron Shale, Silurian, IN – C,2

Cheilotrypa hispida Ulrich – 3 cm field

Cheilotrypa hispida Ulrich – very small branching bryozoan, Glen Dean Fm., Upper Mississippian, KY – C,1,2

Chondaulus ponderosa (Rominger)

Chondaulus ponderosa (Rominger) – a massive species in the Jeffersonville Ls., Middle Devonian, IN, KY – C,1,2

Constellaria florida Ulrich

Constellaria florida Ulrich – with star-shaped monticules, this genus is very distinctive. Occurs most frequently in flat fronds. Six species in the Upper Ordovician, IN, KY – C,1,2

Cyphotrypa clarksvillensis McFarlan

Cyphotrypa clarksvillensis McFarlan# – a massive, often hemispherical trepostome bryozoan of the Upper Ordovician, IN, KY – C,1

Cystodictya lineata Ulrich

Cystodictya lineata Ulrich – flat fronds, Salem Limestone, Middle Mississippian, KY,IN – C,1,2

Dekayia sp.

Dekayia sp. – Branching bryozoan in the Upper Ordovician, IN, KY – C,1,2

Eridotrypa macrostoma                     Upper Mississippian                          KY   C,1,2 on crinoids columns

Eridotrypa sp.                                       Middle Devonian                                IN                           C,1,2

Evactinopora radiata Meek & Worthen – 1.5 cm view

Evactinopora radiata Meek & Worthen# – a star-shaped bryozoan from the Fern Glen Formation in Missouri, MO – C,1,2

Fenestella depressa Hall – this example shows zooid structures, 40x

Fenestella depressa Hall# – in the Jeffersonville Limestone, Middle Devonian. KY – S,2

Fenestella acmea Hall

Fenestella acmea Hall – the Waldron species with smaller fenestrules. Middle Silurian, IN – C1,2

Fenestella multispinosa Ulrich – wet, to see zooids better

Fenestella multispinosa Ulrich – Glen Dean Fm., Upper Mississippian, KY – C,1,2

Fenestella parvulipora Hall – the Waldron species with larger fenestrules. Middle Silurian, IN – C1,2

Fenestella sp. – pyrite-replaced, shows zooids

Fenestella sp. (pyrite-replaced) – from the Coral Ridge fauna, basal Borden Fm., Middle Mississippian.

Fenestella tenax Ulrich – about 1 cm view

Fenestella tenax Ulrich – Glen Dean Fm., Upper Mississippian, KY – C,1,2

Fistulipora concentrica Hall – 2.5 cm view

Fistulipora concentrica Hall – flat to irregular Waldron Shale species. Can get large. Middle Silurian, IN – C,2

Fistulipora spergenensis Hall

Fistulipora spergenensis Hall – abundant bryozoan in Salem Ls., with monticules, Middle Mississippian, IN, KY – C,1,2

Fistulipora sp. from the Bangor Limestone in Alabama

Fistulipora sp. – a common genus spanning the Paleozoic. Abundant in the Upper Mississippian, AL, IN, KY – C,1,2

Fistulipora sp.                                       Middle Devonian                                IN,KY                    C,2

Glyptopora michelinea Prout

Glyptopora michelinea Prout # – a rare, distinctive bryozoan that superficially resembles the tabulate coral Michelinea. IN, KY – C,1

Hederella sp. on Spinocyrtia granulosa (Hall) – Middle Devonian
Hederella encrusting Cystodictya lineata Hall – Middle Mississippian

Hederella sp. on other fossils          Silurian – Mississippian in IN, KY, etc. – C,2

Heterotrypa subfrondosa Cumings – lit by low-angle sunlight to show detail

Heterotrypa subfrondosa Cumings – flattened fronds, large, with monticules. Numerous species of Heterotrypa in the Upper Ordovician, KY – C,1,2

Homotrypa dawsoni ” ”                   KY                          C,1

Homotrypa flabellaris                          ”              ”                                           KY,IN                    C,1

Homotrypella hospitalis (Nicholson)

Homotrypella hospitalis (Nicholson) – massive, often hemispherical, Upper Ordovician, IN, KY – C,1

Lioclema sp. encrusting Mississippian crinoid column. 1 cm view.

Lioclema sp. – often encrusting other fauna. Silurian – Mississippian, KY, TN – C,2

Lyroporella ovalis                                Upper Mississippian                            KY                          C,1

Lyroporella quincuncialis (Hall) – 2 cm field

Lyroporella quincuncialis (Hall)# – fenestrate with a curving base. Upper Mississippian, AL, IN, KY – C,1,2

Monticulapora mammulata                Upper Ordovician                                KY                          C,1

Meekopora exigua                              Upper Mississippian                            KY                          C,1

Parvohallopora oneilli (James) – fragmented large colony
Parvohallopora oneilli (James) – detail, 2 cm view

Parvohallopora oneilli (James) – common in Kope Fm., Upper Ordovician, where storm-shattered colonies are common. IN, KY – C,1,2

Parvohallopora ramosa                        ”               ”                                         KY,IN                    C,1

Parvohallopora subfrondosa               ”               ”                                           KY                         C,1

Peronopora vera                                    ”               ”                                         KY                         C,2

Polypora spp.                                       Middle Devonian                                KY                         C,2

Polypora cestriensis                             Middle & Upper Mississippian         KY,IN                    C,1,2

Polypora corticosa Ulrich

Polypora corticosa Ulrich – Glen Dean Fm., Upper Mississippian, KY – C,1,2

Polypora multispinosa Ulrich – ~2cm view

Polypora multispinosa Ulrich – Glen Dean Fm., Upper Mississippian, KY – C,1,2

Prasopora simulatrix Upper Ordovician                                KY                          C,2

Prismopora serratula Ulrich – ~2 cm view

Prismopora serratula Ulrich – triangular in cross-section, it’s uncommon and small. Glen Dean Fm., Upper Mississippian, KY – C,1,2

Rhopalonaria venosa?                        Upper Ordovician                                KY,IN                    C,2

Saffordotaxis incrassata                    Middle Mississippian                          KY                    C,1 (very small)

Septopora subquadrans Ulrich – 2.5 cm view

Septopora subquadrans Ulrich – easy to identify with “frowning” fenstrules. Glen Dean Fm., Upper Mississippian, IN, KY – C,1,2

Stromatopora sp.                                 Upper Ordovician                                KY                         C,2

Tabulipora ramosa Ulrich                             Upper Mississippian                            IN, KY                   C,1,2

Trematopora sp.

Trematopora sp.# – unknown if this has an updated name, Waldron Shale, Silurian, IN – C,1,2

Unidentified disks                               Middle Devonian                                IN                           S,1