Mazon Creek (Carboniferous of the United States)

Also known as Mazon Creek Vertebrate Fauna, Braidwood Fauna, pit 11

Where: Grundy/Will County, Illinois (41.3° N, 88.1° W: paleocoordinates 4.7° S, 23.2° W)

• coordinate based on political unit

• local area-level geographic resolution

When: Francis Creek Shale Member (Carbondale Formation), Westphalian D (311.4 - 306.9 Ma)

• "Francis Creek Shale above Morris (no. 2) Coal, Carbondale Formation, Westphalian D, Middle Pennsylvanian" (Carroll & Baird, 1972)

•Baird et al. (1985) refer to the no. 2 coal as Colchester or Croweburg Coal Member.

Environment/lithology: deltaic; silty mudstone and nodular siderite

• "...these indicate rapid and often episodic mud deposition in interdistributary bay and prodelta settings." (Baird et al., 1985 p.90)
• "Concretions occur typically in laminated to weakly rippled, silty mudstone deposits which typically show little or no evidence of bioturbation. Small-scale sedimentary structures in nodule-bearing sequences include climbing ripple drift, and soft-sediment load-failure..." (Baird et al., 1985 p.90). Note that this is a general description of the fossil bearing strata of the Francis Creek Shale Member which does not refer specifically to the occurences in the Mazon Creek area proper.

Size class: macrofossils

Preservation: mold/impression, concretion, soft parts, replaced with other

Collected by R. L. Moodie, P. Turnbull, among others in 1871, 1953; reposited in the FMNH, MCZ, USNM, YPM

Collection methods: mechanical,

Primary reference: R. L. Carroll and D. Baird. 1972. Carboniferous Stem-Reptiles of the Family Romeriidae. Bulletin of the Museum of Comparative Zoology 143(5):321-363 [J. Mueller/T. Liebrecht]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 79598: authorized by Johannes Mueller, entered by Jana Dummasch on 14.03.2008, edited by Torsten Liebrecht, Mark Uhen, Matthew Carrano and Emma Dunne

Creative Commons license: CC BY (attribution)

Taxonomic list

Enoplea
 Chromadorida - Nemavermidae
Tullimonstrum gregarius n. gen. n. sp.10
Tullimonstrum gregarius n. gen. n. sp.10
Amphibia
 Temnospondyli - Eobrachyopidae
Isodectes obtusus11 Cope 1868 tetrapod
FMNH PR1036
 Temnospondyli - Branchiosauridae
Eumicrerpeton parvum n. gen. n. sp.8
Eumicrerpeton parvum n. gen. n. sp.8 Moodie 1910 tetrapod
YPM 803 (Holotype: skull (length 0.5cm) in ventral view)
 Temnospondyli - Amphibamidae
"Amphibamus grandiceps n. gen. n. sp." = Amphibamus grandiceps3, "Mazonerpeton longicaudatum n. sp." = Amphibamus grandiceps11, "Micrerpeton caudatum n. gen. n. sp." = Amphibamus grandiceps7
"Amphibamus grandiceps n. gen. n. sp." = Amphibamus grandiceps3 Cope 1865 tetrapod
YPM 794 (Neotype: almost complete skeleton in part and counter part. Holotype was destroyed in a fire)
"Mazonerpeton longicaudatum n. sp." = Amphibamus grandiceps11 Cope 1865 tetrapod
YPM 795 (Holotype)
"Micrerpeton caudatum n. gen. n. sp." = Amphibamus grandiceps7 Cope 1865 tetrapod
 Temnospondyli -
Miobatrachus romeri n. gen. n. sp.11
Miobatrachus romeri n. gen. n. sp.11 Watson 1941 tetrapod
FMNH UC2000 (Holotype)
Osteichthyes
 Aistopoda - Phlegethontiidae
"Phlegethontia mazonensis n. sp." = Phlegethontia longissima4
"Phlegethontia mazonensis n. sp." = Phlegethontia longissima4 Fritsch 1875 tetrapod
USNM 17097 (type); MCZ 2204; FMNH MCP 501*, PR 400*, PR 624, PR 831, PR 1145, PR 1358; asterisks mark specimens reported from Mazon Creek by either McGinnis (1967; as P. cf. P. longissima) or Lund (1978, Ann. Carnegie Mus.; as A. mazonense) but not at all mentioned by Anderson (2002, J. Paleont.); FMNH specimens without asterisk are reported by Anderson (2002) only
 Aistopoda - Pseudophlegethontiidae
Pseudophlegethontia turnbullorum n. gen. n. sp.1 Anderson 2003 tetrapod
FMNH PR 281
 Recumbirostra - Molgophidae
Brachydectes newberryi2 Cope 1868 amniote
USNM 4313
Infernovenator steenae n. gen. n. sp.6 Mann et al. 2019 amniote
Holotype: FMNH PR 4203, a single part concretion containing a nearly complete cranial and postcranial skeleton, preserved as a mould of the dorsal aspect, anterior limbs poorly developed, posterior limbs only represented by single left femur, tail incompletely preserved posteriorly
 Recumbirostra -
Joermungandr bolti n. gen. n. sp.5
Joermungandr bolti n. gen. n. sp.5 Mann et al. 2021 amniote
Holotype: FMNH 1309, part and counterpart of a siderite concretion containing a virtually complete skeleton and soft body impression in dorsal and ventral views
Reptilia
 Eureptilia - Protorothyrididae
Cephalerpeton ventriarmatum n. gen. n. sp. Moodie 1912 eureptile
YPM 796 (type)
Osteichthyes
 Embolomera - Archeriidae
Spondylerpeton spinatum n. gen. n. sp.9
Spondylerpeton spinatum n. gen. n. sp.9 Moodie 1912 tetrapod
Yale U. Mus. No. 793 (126) (Not 26 as in Moodie, 1912)