Arkadelphia Marl

Arkadelphia Marl
Stratigraphic range: Late Maastrichtian
TypeFormation
UnderliesMidway Group
OverliesNacatoch Formation
Thickness120 to 160 feet[1]
Location
RegionArkansas
CountryUnited States
Type section
Named forArkadelphia, Clark County, Arkansas[2]
Named byRobert Thomas Hill

The Arkadelphia Marl, also called the Arkadelphia Formation, is a geologic formation in Arkansas in Clark, Nevada, and Hempstead counties.[3][4] It preserves fossils dating back to the late Maastrichtian stage of the Cretaceous period.

Paleofauna

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Bony fish reported from the Arkadelphia Formation
Genus Species Presence Material Notes Images
Albulidae indet. Indeterminate Cabot, Arkansas.[5] 4 small, eroded otoliths.[5] A bonefish.
Ampheristus A. cf. A. americanus Cabot, Arkansas.[5] 6 otoliths.[5] An ophidiiform.
Anguilla A.? chickasawae Cabot, Arkansas.[5] 6 otoliths.[5] An eel.
Apateodus A. crenellatus? Cabot, Arkansas.[5] 3 otoliths.[5] An aulopiform.
Arius A.? subtilis Cabot, Arkansas.[5] A well-preserved otolith (DMNH 2021-09-11).[5] A catfish.
Clupeiformes? indeterminate Indeterminate Cabot, Arkansas.[5] An eroded, broken otolith (DMNH 2021-09-10).[5] A clupeiform.
Echiophis E. aff. E. semisphaeroides Cabot, Arkansas.[5] 11 otoliths.[5] An eel.
Elopothrissus E. sp. Cabot, Arkansas.[5] One otolith (DMNH 2021-09-03).[5] A bonefish.
Elops E. sp. Cabot, Arkansas.[5] A small, broken otolith (DMNH 2021-09-01).[5] A ladyfish.
Eutawichthys E. maastrichtiensis Cabot, Arkansas.[5] 21 otoliths.[5] A beryciform.
E. cf. E. stringeri Cabot, Arkansas.[5] 48 otoliths.[5] A beryciform.
E. zideki Cabot, Arkansas.[5] 287 otoliths.[5] A beryciform.
Gadiformes indeterminate Indeterminate Cabot, Arkansas.[5] 11 very small or broken otoliths.[5] A gadiform.
Genartina G. sp. 1 Cabot, Arkansas.[5] One otolith (DMNH 2021-09-04).[5]
Kokenichthys K. navis Cabot, Arkansas.[5] 2 eroded otoliths.[5] An osteoglossiform.
Lapillus type 1 Indeterminate Cabot, Arkansas.[5] A small, slightly eroded otolith (DMNH 2021-09-31).[5] An unidentified fish otolith.
Muraenanguilla M.? sp. Cabot, Arkansas.[5] 2 worn, broken otoliths.[5] An eel.
Osmeroides O. sp. Cabot, Arkansas.[5] 3 otoliths.[5]
Palaeogadus P.? belli Cabot, Arkansas.[5] Multiple otoliths.[5] A gadiform.
P. cf. P. weltoni Cabot, Arkansas.[5] A small, slightly eroded otolith (DMNH 2021-09-23).[5] A gadiform.
Protobythites P. brzobohatyi Cabot, Arkansas.[5] 4 otoliths.[5] An ophidiiform.
Tippaha T. mythica Cabot, Arkansas.[5] 8 otoliths.[5] A holocentriform.
Vorishia V. vulpes Cabot, Arkansas.[5] 1,537 otoliths.[5] A catfish.
Rays reported from the Arkadelphia Formation
Genus Species Presence Material Notes Images
Dasyatis D. sp. Ouachita River northwest of Malvern, Arkansas.[6] 3 oral teeth (AMNH 20194-20196) [6] A stingray.
Ischyrhiza I. avonicola Ouachita River northwest of Malvern, Arkansas.[6] 8 teeth (AMNH 20164-20171).[6] A sawskate.
I. mira Ouachita River northwest of Malvern, Arkansas.[6] 3 oral teeth (AMNH 20172-20174).[6] A sawskate.
Ptychotrygon P. cf. P. vermiculata Ouachita River northwest of Malvern, Arkansas.[6] 4 oral teeth (AMNH 20183-20186).[6] A sawskate.
Raja R. farishi Ouachita River northwest of Malvern, Arkansas.[6] 3 oral teeth (AMNH 20187-20189).[6] A skate.
Rhinobatos R. casieri Ouachita River northwest of Malvern, Arkansas.[6] 4 oral teeth (AMNH 20160-20163).[6] A guitarfish.
Rhombodus R. binkhorsti Ouachita River northwest of Malvern, Arkansas.[6] 4 oral teeth (AMNH 20190-20193) [6] A rajiforme.
Schizorhiza S. cf. S. stromeri Ouachita River northwest of Malvern, Arkansas.[6] 5 rostral teeth (AMNH 20178-20182).[6] A sawskate.
Sclerorhynchus S. sp. Ouachita River northwest of Malvern, Arkansas.[6] 3 rostral teeth (AMNH 20175-20177).[6] A sawskate.
Sharks reported from the Arkadelphia Formation
Genus Species Presence Material Notes Images
Carcharias C. cf. C. holmdelensis Ouachita River northwest of Malvern, Arkansas.[6] 5 anterior teeth (AMNH 20139-20143).[6] A sand shark.
Galeorhinus G. girardoti Ouachita River northwest of Malvern, Arkansas.[6] 4 lateral teeth (AMNH 20156-20159). A houndshark.
Ginglymostoma G. lehneri Ouachita River northwest of Malvern, Arkansas.[6] 4 lateral teeth (AMNH 20132-20135).[6] A carpet shark.
Odontaspis O. aculeatus Ouachita River northwest of Malvern, Arkansas.[6] 2 lateral teeth (AMNH 20137 & 20138).[6] A sand shark.
Plicatoscyllium P. cf. P. derameei Ouachita River northwest of Malvern, Arkansas.[6] Lateroanterior tooth (AMNH 20136).[6] A carpet shark.
Serratolamna S. serrata Ouachita River northwest of Malvern, Arkansas.[6] 6 teeth (AMNH 20144-20149).[6] A mackerel shark.
Squalicorax S. kaupi Ouachita River northwest of Malvern, Arkansas.[6] 6 lateral teeth (AMNH 20150-10155).[6] A mackerel shark.
Squatina S. hassei Ouachita River northwest of Malvern, Arkansas.[6] 4 lateral teeth (AMNH 20128-20131).[6] An angelshark.

See also

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References

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  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. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak al am an ao ap aq ar as at 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. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag 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.