LCLU Interstate 30 excavation (Paleocene of the United States)

Where: Hot Spring County, Arkansas (34.4° N, 92.8° W: paleocoordinates 38.4° N, 72.2° W)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Clayton Limestone Formation (Midway Group), Danian (66.0 - 61.6 Ma)

• over 20 m of massive, dark gray

•clays containing invertebrate casts and molds, thin interbedded limestone units, and locally phosphatic, sand and

•pebble lag deposits

Environment/lithology: marine; sandstone

• lag deposit; locally phosphatic, sand and pebble lag deposits

Size classes: macrofossils, mesofossils, microfossils

Preservation: mold/impression, trace, concretion

Primary reference: H. M. Maisch, M. A. Becker, and M. L. Griffiths. 2019. Chondrichthyans from the Lower Clayton Limestone Unit of the Midway Group (Paleocene) near Malvern, Arkansas, USA, with comments on the K/Pg boundary . Palaeontologische Zeitschrift [P. Holroyd/P. Holroyd]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 206776: authorized by Patricia Holroyd, entered by Patricia Holroyd on 01.12.2019

Creative Commons license: CC BY (attribution)

Taxonomic list

• invertebrates, foraminifera, and ichnofossils noted but not fully reported
 Nodosariacea - Nodosariidae
Lenticulina sp. Lamarck 1804
 Decapoda -
Brachyura indet. Latreille 1802 crab
 Protobranchia - Nuculanidae
Nuculana sp. Link 1807 pointed nut clam
 Sorbeoconcha - Turritellidae
Turritella sp. Lamarck 1799 turret shell
Chondrichthyes indet. Huxley 1880 cartilaginous fish
one lamniform type
 Euselachii -
Myliobatiformes indet. Compagno 1973 stingray
 Myliobatiformes - Dasyatidae
Dasyatis sp. Rafinesque 1810 whiptail stingray
Dasyatis cf. hexagonalis Arambourg 1952 whiptail stingray
Hypolophites sp. Leriche 1913 whiptail stingray
 Myliobatiformes - Myliobatidae
Myliobatis sp. Cuvier 1816 eagle ray
Rhinoptera sp. Cuvier 1829 cownose ray
 Lamniformes - Odontaspididae
Odontaspis winkleri Leriche 1905 sand tiger shark
Carcharias sp. Rafinesque 1810 sand shark
Palaeohypotodus rutori sand tiger shark
 Carchariniformes - Triakidae
Palaeogaleus vincenti Daimeries 1889 hound shark
 Orectolobiformes - Ginglymostomatidae
Ginglymostoma subafricanum Arambourg 1952 nurse shark
 Chimaeriformes -
Chimaeriformes indet. Obruchev 1953 chimaera
 Loricata -
Crocodylia indet. crocodilian
 Ichnofossils -
Gastrochaenolites sp. Leymerie 1842
Ophiomorpha sp. Lundgren 1891