MGS Loc. 90 - Ichusa Creek [Mint Spring Fm] (Oligocene of the United States)

Where: Smith County, Mississippi (32.0° N, 89.4° W: paleocoordinates 32.3° N, 82.9° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Mint Spring Formation, Rupelian (33.9 - 28.1 Ma)

• The Mint Spring Formation consists of fossiliferous sands that lie disconformably above the estuarine clays and sands of the Forest Hill Formation. This contact is characterized by shell gravels that are largely comprised of the bivalve "Callista", by lithified clay clasts bored by the bivalve "Jouannetia", and by shark and ray teeth. Lithified clay clasts are especially common at the base of the Mint Spring Formation along the Chickasawhay River in Wayne County. Here clay clasts are numerous enough to have produced a cobble bottom on the Mint Spring sea floor. These clasts formed a hard substrate utilized by a variety of encrusting organisms. The sands of the Mint Spring are moderately clean and often show cross-bedding. These sands indicate a near-shore shelf enviroment. At localities 89 and 90 in Smith County these marine sand facies have well-preserved fossils.

• formation-level stratigraphic resolution

Environment/lithology: offshore; poorly lithified, conglomeratic, calcareous limestone and wackestone

Size class: mesofossils

Preservation: original aragonite, original calcite

Collection methods: bulk, mechanical,

• bivalves only.

Primary reference: D. T. Dockery. 1982. Lower Oligocene Bivalvia of the Vicksburg Group in Mississippi. Mississippi Department of Natural Resources Bureau of Geology 123:1-261 [L. Ivany/S. DeLong/M. Uhen]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 5941: authorized by Linda Ivany, entered by Sarah DeLong on 01.01.2000

Creative Commons license: CC BY (attribution)

Taxonomic list

• list uses catagories. For example, R = rare, 9 valves or less. C = common, 10-99 valves. A = abundant,100+ valves collected.

•Categories are listed in the comments field, absolute abundances are given in the abundance field.

•Since taxa with greater than 99 specimens were not counted with absolute abundances, these were reported with category "A" for abundant.

 Dentaliida - Dentaliidae
 Carditida - Astartidae
Astarte menthifontis n. sp. Dockery 1982 clam
C category
 Carditida - Carditidae
"Venericardia carsonensis" = Venericardia (Rotundicardia) carsonensis
"Venericardia carsonensis" = Venericardia (Rotundicardia) carsonensis Dall 1903 clam
C category
 Poromyida - Cuspidariidae
Plectodon intastriata clam
R category
 Poromyida - Spheniopsidae
 Poromyida - Verticordiidae
Verticordia dalliana clam
C category
 Cardiida - Sportellidae
Sportella oblonga Conrad 1848 clam
R category
 Cardiida - Veneridae
Pitar aldrichi n. sp. venus clam
C category
Pitar calcanea venus clam
R category
"Chione victoria" = Lirophora (Lirophora) victoria Dall 1982 venus clam
R category
 Cardiida - Kelliellidae
Kelliella rufaripa n. sp. clam
R category
 Cardiida - Ungulinidae
"Diplodonta eburnea" = Diplodonta (Diplodonta) eburnea
"Diplodonta eburnea" = Diplodonta (Diplodonta) eburnea Conrad 1848 clam
R category
 Cardiida - Tellinidae
Tellina subprotexta n. sp. tellin clam
C category
 Cardiida - Semelidae
Ervilia exterolaevis n. sp. clam
R category
Semelina pilsbryi clam
R category
 Cardiida - Cardiidae
Trigoniocardia silvacollina n. sp. Dockery 1982 cockle
R category
"Nemocardium diversum" = Nemocardium (Nemocardium) diversum Conrad 1848 cockle
R category
Agnocardia glebosum Conrad 1848 cockle
R category
Trachycardium eversum Conrad 1848 cockle
R category
Laevicardium leptorimum n. sp. Dockery 1982 cockle
R category
 Pholadida - Corbulidae
Corbula engonata, "Corbula laqueata" = Varicorbula laqueata
Corbula engonata Conrad 1848 clam
C category
"Corbula laqueata" = Varicorbula laqueata Casey 1903 clam
C category
 Hiatellida - Hiatellidae
Panopea oblongata Conrad 1848 clam
R category
 Lucinida - Lucinidae
Myrtea vicksburgensis Casey 1903 clam
C category
Lucina posteocurta n. sp. Dockery 1982 clam
R category
Lucina imbricolamella n. sp. Dockery 1982 clam
C category
 Arcida - Glycymerididae
Glycymeris intercostata Gabb 1860 clam
C category
Glycymeris suwannensis Mansfield 1937 clam
C category
 Arcida - Arcidae
Scapharca delicatula Casey 1903 clam
C category
 Pectinida - Pectinoidae
"Eburneopecten subminutus" = Eburneopecten (Eburneopecten) subminutus, "Chlamys menthifontis" = Chlamys (Lyropecten) menthifontis
"Eburneopecten subminutus" = Eburneopecten (Eburneopecten) subminutus Aldrich 1903 scallop
C category
"Chlamys menthifontis" = Chlamys (Lyropecten) menthifontis Glawe 1970 scallop
R category
 Ostreida - Ostreidae
Ostrea sp. Linnaeus 1758 oyster
R category
Ostrea paroxis Lesueur 1829 oyster
R category
 Mytilida - Crenellidae
Crenella fenestra n. sp. Dockery 1982 clam
C category
 Nuculida - Nuculidae
Nucula vicksburgensis Conrad 1848 nut clam
C category
 Sorbeoconcha - Vermetidae
Serpulorbis sp. Sasso 1827 worm shell
 Neogastropoda - Cochlespiridae
"Tropiscurcula caseyi" = Tropisurcula
"Tropiscurcula caseyi" = Tropisurcula snail
 Neogastropoda - Borsoniidae
 Neogastropoda - Olivellidae
"Oliva mississippiensis" = Agaronia mississippiensis
"Oliva mississippiensis" = Agaronia mississippiensis Conrad 1848 snail
 Neogastropoda - Costellariidae
Conomitra vicksburgensis ribbed mitre
Conomitra vicksburgensis laevigata
Conomitra crenulata ribbed mitre
Conomitra crenulata modesta
Microsurcula mentha n. sp. ribbed mitre
 Neogastropoda - Cancellariidae
Agatrix mississippiensis, "Olssonella elongata n. sp." = Axelella
"Olssonella elongata n. sp." = Axelella snail
 Heterostropha - Acteonidae
Acteon menthafons n. sp. snail
Acteon punctatus n. sp. snail
 Lepetellida - Lepetellidae
Merisca aequistriata
"Tellina lintea" = Merisca aequistriata
"Tellina lintea" = Merisca aequistriata Say 1824
R category