Hogback South, MNA Locality B (Cretaceous of the United States)

Also known as #88

Where: San Juan County, New Mexico (36.5° N, 108.5° W: paleocoordinates 43.8° N, 79.8° W)

• coordinate stated in text

• outcrop-level geographic resolution

When: Fruitland Formation, Late/Upper Campanian (83.5 - 70.6 Ma)

• within the upper 15.2 m of the Fruitland. Two fossil horizons, approx. 20cm apart.

• group of beds-level stratigraphic resolution

Environment/lithology: marine; concretionary, ferruginous mudstone and calcareous sandstone

Size classes: macrofossils, mesofossils

Collection methods: bulk, surface (float), chemical, sieve,

• MNA locality #88, used tandem screen boxes, with 1/16 inch mesh size and 1/25 inch mesh. Some samples were disaggregated using Amine 220 and Methyl Amyl Alcohol.

Primary reference: J. G. Armstrong-Ziegler. 1978. An aniliid snake and associated vertebrates from the Campanian of New Mexico. Journal of Paleontology 52(2):480-483 [J. Alroy/E. Leckey/E. Leckey]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 36541: authorized by John Alroy, entered by Erin Leckey on 03.02.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

Bivalvia
 Pholadida - Pholadidae
Chondrichthyes
 Sclerorhynchiformes - Sclerorhynchidae
Ischyrhiza avonicola Estes 1964 cartilaginous fish
 Hybodontiformes - Lonchidiidae
Lonchidion selachos Estes 1964 elasmobranch
 Myliobatiformes - Dasyatidae
Myledaphus bipartitus Cope 1876 whiptail stingray
 Lamniformes - Lamnidae
Isurus sp. Agassiz 1843 mako shark
I. (Oxyrhina) sp.
 Orectolobiformes - Orectolobidae
Squatirhina sp. Casier 1947 wobbegong
Squatirhina americana Estes 1964 wobbegong
Actinopteri
 Acipenseriformes - Polyodontidae
Paleopsephurus wilsoni MacAlpin 1947 paddlefish
 Acipenseriformes - Acipenseridae
Acipenser eruciferus Cope 1876 sturgeon
 Elopiformes - Phyllodontidae
Paralbula casei Estes 1969
 Amiiformes - Amiidae
Amia fragosa Jordan 1927 bowfin
 Lepisosteiformes - Lepisosteidae
Reptilia
 Avetheropoda -
Paronychodon lacustris Cope 1876 coelurosaur
 Neornithischia - Pachycephalosauridae
? Pachycephalosauridae indet. Sternberg 1945 ornithischian
isolated tooth
 Neornithischia - Hadrosauridae
Kritosaurus navajovius Brown 1910 hadrosaurine
several isolated teeth
 Crocodylia - Alligatoridae
Brachychampsa sp. Gilmore 1911 crocodilian
isolated teeth
Mammalia
 Multituberculata - Eucosmodontidae
Eucosmodontidae indet. Jepsen 1940 multituberculate