Arkadelphia Marl

Arkadelphia Marl
Stratigraphic range: Late Maastrichtian
TypeFormation
UnderliesMidway Group
OverliesNacatoch Formation
Thickness120 to 160 feet
Location
RegionArkansas
CountryUnited States
Type section
Named forArkadelphia, Clark County, Arkansas
Named byRobert Thomas Hill

The Arkadelphia Marl, also called the Arkadelphia Formation, is a geologic formation in Arkansas in Clark, Nevada, and Hempstead counties. It preserves fossils dating back to the late Maastrichtian stage of the Cretaceous period.

Paleofauna

Bony fish

Bony fish reported from the Arkadelphia Formation
GenusSpeciesPresence MaterialNotesImages
Albulidae indet. Indeterminate Cabot, Arkansas. 4 small, eroded otoliths. A bonefish.
Ampheristus A. cf. A. americanus Cabot, Arkansas. 6 otoliths. An ophidiiform.
Anguilla A.? chickasawae Cabot, Arkansas. 6 otoliths. An eel.
Apateodus A. crenellatus? Cabot, Arkansas. 3 otoliths. An aulopiform.
Arius A.? subtilis Cabot, Arkansas. A well-preserved otolith (DMNH 2021-09-11). A catfish.
Clupeiformes? indeterminate Indeterminate Cabot, Arkansas. An eroded, broken otolith (DMNH 2021-09-10). A clupeiform.
Echiophis E. aff. E. semisphaeroides Cabot, Arkansas. 11 otoliths. An eel.
Elopothrissus E. sp. Cabot, Arkansas. One otolith (DMNH 2021-09-03). A bonefish.
Elops E. sp. Cabot, Arkansas. A small, broken otolith (DMNH 2021-09-01). A ladyfish.
Eutawichthys E. maastrichtiensis Cabot, Arkansas. 21 otoliths. A beryciform.
E. cf. E. stringeri Cabot, Arkansas. 48 otoliths. A beryciform.
E. zideki Cabot, Arkansas. 287 otoliths. A beryciform.
Gadiformes indeterminate Indeterminate Cabot, Arkansas. 11 very small or broken otoliths. A gadiform.
Genartina G. sp. 1 Cabot, Arkansas. One otolith (DMNH 2021-09-04).
Kokenichthys K. navis Cabot, Arkansas. 2 eroded otoliths. An osteoglossiform.
Lapillus type 1 Indeterminate Cabot, Arkansas. A small, slightly eroded otolith (DMNH 2021-09-31). An unidentified fish otolith.
Muraenanguilla M.? sp. Cabot, Arkansas. 2 worn, broken otoliths. An eel.
Osmeroides O. sp. Cabot, Arkansas. 3 otoliths.
Palaeogadus P.? belli Cabot, Arkansas. Multiple otoliths. A gadiform.
P. cf. P. weltoni Cabot, Arkansas. A small, slightly eroded otolith (DMNH 2021-09-23). A gadiform.
Protobythites P. brzobohatyi Cabot, Arkansas. 4 otoliths. An ophidiiform.
Tippaha T. mythica Cabot, Arkansas. 8 otoliths. A holocentriform.
Vorishia V. vulpes Cabot, Arkansas. 1,537 otoliths. A catfish.

Rays

Rays reported from the Arkadelphia Formation
GenusSpeciesPresence MaterialNotesImages
Dasyatis D. sp. Ouachita River northwest of Malvern, Arkansas. 3 oral teeth (AMNH 20194-20196) A stingray.
Ischyrhiza I. avonicola Ouachita River northwest of Malvern, Arkansas. 8 teeth (AMNH 20164-20171). A sawskate.
I. mira Ouachita River northwest of Malvern, Arkansas. 3 oral teeth (AMNH 20172-20174). A sawskate.
Ptychotrygon P. cf. P. vermiculata Ouachita River northwest of Malvern, Arkansas. 4 oral teeth (AMNH 20183-20186). A sawskate.
Raja R. farishi Ouachita River northwest of Malvern, Arkansas. 3 oral teeth (AMNH 20187-20189). A skate.
Rhinobatos R. casieri Ouachita River northwest of Malvern, Arkansas. 4 oral teeth (AMNH 20160-20163). A guitarfish.
Rhombodus R. binkhorsti Ouachita River northwest of Malvern, Arkansas. 4 oral teeth (AMNH 20190-20193) A rajiforme.
Schizorhiza S. cf. S. stromeri Ouachita River northwest of Malvern, Arkansas. 5 rostral teeth (AMNH 20178-20182). A sawskate.
Sclerorhynchus S. sp. Ouachita River northwest of Malvern, Arkansas. 3 rostral teeth (AMNH 20175-20177). A sawskate.

Sharks

Sharks reported from the Arkadelphia Formation
GenusSpeciesPresence MaterialNotesImages
Carcharias C. cf. C. holmdelensis Ouachita River northwest of Malvern, Arkansas. 5 anterior teeth (AMNH 20139-20143). A sand shark.
Galeorhinus G. girardoti Ouachita River northwest of Malvern, Arkansas. 4 lateral teeth (AMNH 20156-20159). A houndshark.
Ginglymostoma G. lehneri Ouachita River northwest of Malvern, Arkansas. 4 lateral teeth (AMNH 20132-20135). A carpet shark.
Odontaspis O. aculeatus Ouachita River northwest of Malvern, Arkansas. 2 lateral teeth (AMNH 20137 & 20138). A sand shark.
Plicatoscyllium P. cf. P. derameei Ouachita River northwest of Malvern, Arkansas. Lateroanterior tooth (AMNH 20136). A carpet shark.
Serratolamna S. serrata Ouachita River northwest of Malvern, Arkansas. 6 teeth (AMNH 20144-20149). A mackerel shark.
Squalicorax S. kaupi Ouachita River northwest of Malvern, Arkansas. 6 lateral teeth (AMNH 20150-10155). A mackerel shark.
Squatina S. hassei Ouachita River northwest of Malvern, Arkansas. 4 lateral teeth (AMNH 20128-20131). An angelshark.

See also

References

  1. ↑ McFarland, John David (2004) [1998]. "Stratigraphic summary of Arkansas" (PDF). Arkansas Geological Commission Information Circular. 36: 31. Archived from the original (PDF) on 2016-12-21. Retrieved 2018-01-12.
  2. ↑ Hill, R.T. (1888). "The Neozoic geology of southwestern Arkansas". Arkansas Geological Survey Annual Report 1888. 2: 33, 39, 53–56, 72, 188.
  3. ↑ "ARKADELPHIA MARL/FORMATION". Archived from the original on 2016-08-19. Retrieved 2016-07-31.
  4. ↑ "Arkadelphia Marl (ARKad;0)".
  5. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 Stringer, Gary L.; Sloan, James Carson (2023-05-25). "First Cretaceous teleostean otolith assemblage (Arkadelphia Formation, upper Maastrichtian) from Arkansas, USA, early Gadiformes, and the Western Interior Seaway". PaleoBios. 40 (3). doi:10.5070/P940361192. ISSN 2373-8189.
  6. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 Becker, Martin A.; Chamberlain Jr, John A.; Wolf, George E. (2006). "Chondrichthyans from the Arkadelphia Formation (Upper Cretaceous: Upper Maasstrichtian) of Hot Spring County, Arkansas". Journal of Paleontology. 80 (4): 700–716.