Mazon Creek Fossil Fauna

Tetrapods, Aistopods, and Larval Fish 

Tetrapods

Isodectus obtusus - (Cope) Sequeira, 1998

Amphibamus grandiceps - Cope, 1865

Undescribed Genus and Species

                 Douglass collection, Figure 145.2 The Mazon Creek Fossil Fauna 2012 (misidentified as Amphibamus grandiceps)

Cephalerpeton ventriarmatum - Moodie, 1912

Diablorotor bolti - Mann and Maddin, 2019

Joermungandr bolti - Mann et al., 2021

Infernovenator steenae - Mann et al., 2019

Nagini mazonensis - Mann et al., 2022

                                            Above and below: Nagini mazonensis - Milwaukee Public Museum VP35922.1 
                                                          Milwaukee Public Museum collection VP35922.1 (detail)

Undescribed Tetrapod

                                                              Milwaukee Public Museum collection VP395245.1       
                                                          Milwaukee Public Museum collection VP359245.1 (detail)

Undescribed Larval Tetrapod

                Above and below: undescribed larval tetrapod, Pit 11, Braidwood, IL - Field Museum collection PR 5105 (R.Rock)

Larval Branchiosaurid

                         Above and below: larval branchiosaurid temnospondyl, Mazon River, Morris, IL - A.Young collection
                                        Figure 19.8, Page 260, Richardson's Guide to The Fossil Fauna of Mazon Creek 1997.

Larval Amphibamid

         Above and below: larval amphibamid temnospondyl, Mazon River, Morris, IL - B.Riegler collection (photos by B.Riegler)

Aistopods

Phlegethontia longissima - Fritsch, 1875

Snake-like tetrapodomorph

Oestocephalus amphiuminus - Cope, 1868

Pseudophlegethontia turnbullorum - Anderson, 2003

Fish Larvae

Esconichthys apopyris - Bardack, 1974

Commonly called Blades

Described as possibly being a larval lungfish or undescribed amphibian larva, today this form is thought be a group of different, poorly understood larval fish. At least two body forms are now distinguished from Bardack's original description, each representing a new and difficult-to-interpret taxon.

Flathead Form: dorsal views

                                          Esconichthys apopyris, Flathead form, Pit 11, Braidwood, IL - A.Young collection

Flathead Form: oblique and lateral views

                                        Esconichthys apopyris, Flathead form, Pit 11, Braidwood, IL - A.Young collection
                      MPM VP359201.1
                     MPM VP359200
                      MPM VP1382.1

Lateral views

                                                         Esconichthys apopyris, Flathead form - J.Wittry collection
                                                        Esconichthys apopyris, Milwaukee Public Museum VP932.1
                                                          Esconichthys apopyris, Flathead Form - R.Rock collection
                                                                                                                                                  R.Rock collection
                     Esconichthys apopyris with a Peachocaris strongi shrimp - R.Rock collection (positive and negative halves)
                                  Esconichthys apopyris, Flathead form, lateral view, Pit 11, Braidwood, IL - A.Young collection

Snubnose Form: oblique views

                                                                          Milwaukee Public Museum VP359288.2

Snubnose Form: growth series

                                                                       J.Wittry collection
                                                                C.Davis collection
                    Esconichthys apopyris, Snubnose form - Milwaukee Public Museum collection VP359216.2 and VP359216.1