Richards Spur: Artinskian, Oklahoma
collected by F. E. Peabody, W. Langston, J. Bolt, E. C. Olson, among others

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Amphibia - Temnospondyli
? Eryops sp. Cope 1877
Olson 1991 1 individual
UCLA 1751 (fragment of squamosal of large individual)
    = Temnospondyli indet. von Zittel 1887
Polley and Reisz 2011
Amphibia - Temnospondyli - Micropholidae
Tersomius sp. Case 1910
Bolt 1980 1 individual
FMNH UR 1092 (small dentary)
Tersomius dolesensis n. sp. Anderson and Bolt 2013
Anderson and Bolt 2013
OMNH 3709 (Holotype: nearly complete skull), first reported as Tersomius sp. by Bolt (1980), found at Dolese Brothers Limestone quarry
Pasawioops mayi n. gen., n. sp. Fröbisch and Reisz 2008
Fröbisch and Reisz 2008 2 individuals
OMNH 73019 (type), 73509
Amphibia - Temnospondyli - Amphibamidae
Doleserpeton annectens n. gen., n. sp. Bolt 1969
Bolt 1969
FMNH UR 1308 (type); "Referred specimens are too numerous to list; all are in the Field Museum"
Amphibia - Temnospondyli - Trematopidae
Trematopsidae indet. Williston 1910
Bolt 1974 1 individual
FMNH UR 2400 (partial skull)
Acheloma cf. cumminsi Cope 1882
Sullivan et al. 2000 2 individuals
OMNH 56864-56866
Acheloma dunni n. sp. Polley and Reisz 2011
Polley and Reisz 2011 6 specimens
OMNH 73281, nearly complete skull. BMRP2007.3.4, small trematopid skull; BMRP2007.3.1, trematopid snout; OMNH 52365, jaw articulation; OMNH 73514, pelvic girdle; OMNH 52545, right humerus.
Amphibia - Temnospondyli - Dissorophidae
Dissorophidae indet. Boulenger 1902
Sullivan et al. 2000 1 individual
OMNH 56870 (palatine); "clearly does not pertain to either Cacops or Acheloma"
cf. Cacops sp. Williston 1910
Sullivan et al. 2000 1 individual
OMNH 56868 (femur), 56869 (humerus; "probably but not necessarily the same taxon represented by the femur")
Cacops cf. aspidephorus Williston 1910
Bolt 1977 7 individuals
FMNH 1032, 1033 (both are isolated quadrates), 1034 (palatine); catalogue numbers of other specimens (13 palatines total, 14 quadrates total) are not given; estimation of minimum number of individuals is based on the presence of 14 quadrates (1 measurement)
    = Cacops morrisi n. sp. Reisz et al. 2009
Reisz et al. 2009
OMNH 53077 (type) and OMNH 53073; may include FMNH material, which in any case is definitely not C. aspidephorus
Cacops woehri n. sp. Froebisch and Reisz 2012
Schoch and Milner 2014
OMNH 73216 (Holotype: partial skull) and BMRP 2007.3.5 (Frobisch et al., 2015)
cf. Aspidosaurus sp. Broili 1904
Gee et al. 2019
ROMVP 80069 (osteoderms and neural spines)
Dissorophinae indet. Boulenger 1902
Gee and Reisz 2018
OMNH 73522a, anterior trunk and hindlimb
Dissorophus cf. multicinctus Cope 1895
Gee et al. 2019
ROMVP 80072 (partial, disarticulated posterior skull table and occiput in articulation with a series of osteoderms covering 13 vertebral positions); ROMVP 80073 (partial, articulated posterior skull and occiput in articulation with a series of nine osteoderm positions and clavicle); ROMVP 80074 (anterior shield with corresponding anteriormost internal osteoderm); ROMVP 80075 (anterior shield); ROMVP 80076 (internal osteoderm articulated with fragmentary internal-external pair and partial neural spines); ROMVP 80077 (articulated series of osteoderms with possible interclavicle)
Amphibia - Hapsidopareiidae
Llistrofus pricei n. gen., n. sp. Carroll and Gaskill 1978
Carroll and Gaskill 1978 1 individual
FMNH UR 948 (type)
Gymnarthridae
Cardiocephalus cf. sternbergi Broili 1904
Gregory et al. 1956 25 individuals
OUSM 10001 (formerly OU 1034); YPM 3689; KUMNH 8967
    = Cardiocephalus peabodyi n. sp. Carroll and Gaskill 1978
Carroll and Gaskill 1978
type is OUSM 10001; authors report "much other disarticulated material"; number of individuals rests on statement by Gregory et al. (1956) that Euryodus and Cardiocephalus "On the basis of frequency of occurrence of dentaries and maxillaries [...] are about equally abundant at Fort Sill."
Euryodus sp. Olson 1939
Gee et al. 2020
OMNH 53519 (skull with mandibles); FMNH PR 1030 (partial skull with mandibles)
Parareptilia indet. (Lawrence 1868)
Sullivan and Reisz 1999 45 individuals
referred to as "species x" ("either microsaur or reptile") by Bolt (1980); minimum number of individuals is derived from the presence of 91 dentaries (minus OMNH 71111) assigned to "x" by Bolt (1980; specimens mentioned and figured therein are: FMNH PR 1083 (maxilla), 1084-1086 (dentaries), 1087 (premax.), 1091 (maxilla), 1162 (dentary), 1180, 1181 (both are premaxillae))
    = ? Bolterpeton sp. Anderson and Reisz 2003
Anderson and Reisz 2003
additional specimen listed in this reference: OMNH 71112; for further details see comments on taxonomic list
Bolterpeton carrolli n. gen., n. sp. Anderson and Reisz 2003
Anderson and Reisz 2003 2 individuals
OMNH 52364 (type), OMNH 71111 (both are incomplete mandibles); the second specimen probably was originally identified as "species x" by Bolt (1980) (see comments on taxonomic list)
Ostodolepidae
Nannaroter mckinziei n. gen., n. sp. Anderson et al. 2009
Anderson et al. 2009 1 individual
OMNH 73107 (type)
Reptilia
Microleter mckinzieorum n. gen., n. sp. Tsuji et al. 2010
Tsuji et al. 2010 1 individual
OMNH 73106 (type)
Reptilia - Bolosauridae
Bolosaurus sp. Cope 1878
Sullivan and Reisz 1999 3 elements
    = Bolosaurus grandis n. sp. Reisz et al. 2002
Reisz et al. 2002
OMNH 15104, 52311 (type), 56818
Reptilia - Acleistorhinidae
Acleistorhinidae indet. Daly 1969
Modesto et al. 2009 1 individual
OMNH 73364 (one skull; apparently not among the material referred to Delorhynchus cifellii by Reisz et al., 2014)
Feeserpeton oklahomensis n. gen., n. sp. MacDougall and Reisz 2012
MacDougall and Reisz 2012 1 individual
OMNH 73541 (type, a nearly complete skull)
Delorhynchus multidentatus n. sp. Rowe et al. 2021
Rowe et al. 2021
ROMVP 87042, fragmentary skull
Delorhynchus cifellii n. sp. Reisz et al. 2014
Reisz et al. 2014 4 specimens
OMNH 73515 (holotype), OMNH 73362 and 73363 (skull and mandible, cited as "acleistorhinid parareptile" in Modesto et al., 2009), 73524 (a right maxilla)
Delorhynchus priscus n. gen., n. sp. Fox 1962
Fox 1962 3 fragments
KU 11117 (type), 11118, 11119 (all are fragmentary maxillae)
Colobomycter vaughni n. sp. MacDougall et al. 2016
MacDougall et al. 2016
UWBM 96304 (Holotype: partial skull with a few disarticulated cranial and postcranial elements) and BMRP 2008.3.3b (interior surface of a partial skull and two disarticulated vertebrae), found at Dolese Brothers Limestone quarry
Colobomycter pholeter n. gen., n. sp. Vaughn 1958
Vaughn 1958 3 individuals
FMNH UR 272 (type); OMNH 55927, 73535; ROM 26108; specimen numbers of other than the type specimen are from Modesto & Reisz (2008)
Reptilia - Nyctiphruretidae
Abyssomedon williamsi n. gen., n. sp. MacDougall and Reisz 2014
MacDougall and Reisz 2014 1 individual
BMRP 2008 33a
Reptilia
? Diapsida indet. Osborn 1903
Carroll 1968 1 element
YPM 4926 (a single parietal bone)
    = Neodiapsida indet. Benton 1985
Sullivan and Reisz 1999
Orovenator mayorum n. gen., n. sp. Reisz et al. 2011
Reisz et al. 2011 2 individuals
OMNH 74606 (type), 74607; both are partial skulls
Reptilia - Captorhinidae
Captorhinidae indet. Case 1911
Modesto 1996 2 specimens
OMNH 52366, 52367
Labidosauriscus richardi n. gen., n. sp. Modesto et al. 2018
Modesto et al. 2018 8 individuals
OMNH 77609, a partial subadult skull with associated vertebrae (holotype). OMNH 77610, greater part of a mostly articulated, dorsoventrally-compressed skull with a few postcra- nial elements; OMNH 77611, a right premaxilla; OMNH 77612, greater part of a small left maxilla with 11 tooth positions; OMNH 77613, fragment of anterior end of medium-sized right maxilla with three complete teeth and a single alveolus; OMNH 77614, fragment of anterior end of small, right maxilla with two complete teeth and two tooth stumps; OMNH 78657, fragment of small, right maxilla with two complete teeth and a large alve- olus; OMNH 78658, anterior fragment of large, right dentary with two complete teeth.
Labidosaurus sp. Cope 1896
Gregory et al. 1956 6 specimens
    = Labidosaurus cf. hamatus Cope 1896
Olson 1967
FMNH UR 403 "many dentaries", 404 "many maxillae"
    = Eocaptorhinus laticeps Williston 1909
Heaton 1979
    = Captorhinus sp. Cope 1896
Kissel et al. 2002
additional specimens: FMNH PR 927, 949 to 951 (mentioned, in part figured, and referred to Captorhinus aguti by Bolt & DeMar, 1975, J. Paleont. 49(5)) ; "likely referable to C. magnus, although the incomplete nature of the specimens prevents positive assignment"
Captorhinus aguti (Cope 1882)
Sullivan and Reisz 1999 91 individuals
AMNH 2463-2466, 4434, 5494, AMNH unnumbered; FMNH UR 338, 339, 382-402, 425, 594-596, UC 1699, 3x UC unnumbered; UMMP 50985, KU 9978, 8962-8964, 8965, 9780, 9924, Clarke Collection unnumbered specimen (disarticulated partial skull); MCZ 1198, 1199, 2146; OMNH 15138; ROM 30096-30101; specimen numbers are from Seltin (1959), Fox & Bowman (1966), Holmes (1977), Sumida (1987) and Modesto (1998); minimum number of individuals is derived from the presence of 91 interclavicles (incl. more or less complete skeletons)
Captorhinus magnus n. sp. Kissel et al. 2002
Kissel et al. 2002 6 individuals
OMNH 55386, 55387 (type), 55390-55392, 55396, 55397, 55399, 55400, 56820, 56821, 56881, 56884-56886, 56888, 56891, 56893-56897, 56900, 56909-56913, 56917, 56921, 56923, 56929, 56943, 56961, 56963, 56965, 56967, 56970, 56973, 56975, 56983, 56984; presence of 6 left humeri indicates that, at least, 6 individuals are present
Captorhinus kierani deBraga et al. 2019
deBraga et al. 2019
OMNH 73281a (Holotype: complete skull); ROMVP 80229 (right dentary)
Euryodus primus Olson 1939
Gregory et al. 1956 25 individuals
YPM 3684, 3686, 3864-3866 (all are mandibles ore maxillaries) + "numerous isolated bones" in the collections of the KUMNH (number of individuals is inferred from presence of at least 50 dentaries)
    = Euryodus cf. primus Olson 1939
Carroll and Gaskill 1978
additional material: MCZ 4353, 4354; FMNH UR 287 (2 dentaries + 1 atlas), 983
    = Opisthodontosaurus carrolli Reisz et al. 2015
Reisz et al. 2015
Opisthodontosaurus carrolli n. gen., n. sp. Reisz et al. 2015
Reisz et al. 2015 6 individuals
OMNH 77469 (type, a partial skull with mandible), 43299 (a right maxilla), 43300 (left dentary), 77470 (partial skull roof and lower jaw preserved in articulation) 77471 (partial skull and lower jaws, incl. disarticulated vertebrae, pectoral girdle, right forelimb, proximal head of left humerus) and 77472 (partial lower jaws, left maxilla and fragmentary skull roof elements, partial palate, isolated dorsal vertebrae and ribs, two caudal vertebrae, partial right pelvis and femur); ROM 71398 (a single maxillary tooth); UWBM 89171 (lower jaws, partial palate, fragment of lacrimal and prefrontal)
Baeotherates fortsillensis n. gen., n. sp. May and Cifelli 1998
May and Cifelli 1998 1 individual
OMNH 55758 (type)
Reptilia - Protorothyrididae
Protorothyrididae indet. Price 1937
Reisz 1980 9 elements
ROM 21732 to 21740 (all are isolated longbones of fore- and hindlimb)
Varanopidae
Thrausmosaurus serratidens n. gen., n. sp. Fox 1962
Fox 1962 3 fragments
KU 11120 (type), 11121, 11122 (all are dentigerous fragments)
Varanopseidae indet. (Romer and Price 1940)
Sullivan and Reisz 1999 3 individuals
"large"
    = Varanops cf. brevirostris Williston 1911
Maddin et al. 2006
OMNH 73156-73178; "At least three individuals are represented, as indicated by the presence of two parabasisphenoid complexes in one block and the maxilla from another non-associated block."
? Mycterosaurus sp. Williston 1915
Olson 1967 10 elements
FMNH UR 381 (pars; a tibia) "identification questionable"
    = Mycterosaurus longiceps Williston 1915
Reisz et al. 1997
additional elements: KUVP 8970 (maxillary), 85170 (vertebra), 87324 (premaxilla); FMNH UR 381 (pars; axis + cervical), PR 1664 (scapulocoracoid); OMNH 52368 (humerus), 52369 (one of several femora), 52543 (humerus)
Mycterosaurinae indet. Modesto et al. 2001
Evans et al. 2009 3 specimens
OMNH 73208, 73209, 73500; "large undescribed mycterosaurine"
    = Mesenosaurus efremovi n. sp. Maho et al. 2019
Maho et al. 2019
OMNH 73208, OMNH 73209, OMNH 73500
Basicranodon fortsillensis n. gen., n. sp. Vaughn 1958
Olson 1967 1 individual
USNM 21895 (type)
    = Mycterosaurinae indet. Modesto et al. 2001
Maho et al. 2019
Sphenacodontidae
Sphenacodontidae indet. Marsh 1878
Evans et al. 2009 6 specimens
OMNH 73811-73816 (2 dentigerous fragments, 3 isolated teeth, 1 cervical)
Dimetrodon sp. Cope 1878
Brink et al. 2019
ROM 73635, 73636 (isolated teeth); ROM 73637 (neural spine)
Caseidae
Caseidae indet. Williston 1911
Sullivan and Reisz 1999 1 individual
    = Oromycter dolesorum n. gen., n. sp. Reisz 2005
Reisz 2005
FMNH PR 2281 (type), 2282-2290; "there is evidence to suggest that the cranial elements described here may have been derived from a single individual"
Arisierpeton simplex Reisz 2019
Reisz 2019
GAA 00225-1 (Holotype: premaxilla); GAA 00242, a right premaxilla; GAA 00239, a right premaxillary fragment; GAA 00207, a left maxillary fragment; GAA 00225-2, a right maxillary fragment; GAA 00240, a left maxillary fragment with two teeth and fragments of two other teeth; GAA 00246-1, a partial left dentary with eight teeth; GAA 00246-2, a partial right dentary with 12 teeth or parts of teeth; GAA 00244, a series of three dorsal vertebrae.
Seymouriidae
Seymouria sp. Broili 1904
Sullivan and Reisz 1999 7 elements
FMNH PR 2053 (femur), 2054 (humerus), 2055-2057; OMNH 15108, 56825 (all vertebral elements)
Phlegethontiidae
Aistopoda indet.
Gregory et al. 1956 7 specimens
only one single Aistopod vertebra was known from Ft. Sill at the time
    = Phlegethontia cf. longissima Fritsch 1875
McGinnis 1967
UCMP 62580 (braincase), 63835 (two fused vertebrae), 63831 to 63834; YPM 3701 (all are isolated vertebrae)
    = Sillerpeton permianum n. gen., n. sp. Lund 1978
Lund 1978
type is UCMP 62580 (but see comments on taxonomic list)
Chondrichthyes - Xenacanthida - Orthacanthidae
? Orthacanthus sp. Agassiz 1843
Olson 1991
unclassified
Arthropoda indet. Latreille 1829
Modesto et al. 2009 2 elements
cuticle fragments preserved on the palate of acleistorhinid reptiles OMNH 73362 (presumably part of an antenna) and ONMH 73364 (presumably a cercus)
Myriapoda
Helminthomorpha indet. (Pocock 1887)
Hannibal and May 2020 2 specimens
OU 12150, 12151
Dolesea subtila n. gen., n. sp. Hannibal and May 2020
Hannibal and May 2020 1 specimen
OU 12152, 12153
Myriapoda - Oklahomasomatidae
Oklahomasoma richardsspurense n. gen., n. sp. Hannibal and May 2020
Hannibal and May 2020 1 specimen
OU 44526
Myriapoda
Karstiulus fortsillensis n. gen., n. sp. Hannibal and May 2020
Hannibal and May 2020 1 specimen
OU 12154
see common names

Geography
Country:United States State/province:Oklahoma County:Comanche
Coordinates: 34.8° North, 98.4° West (view map)
Paleocoordinates:0.8° North, 28.6° West
Basis of coordinate:estimated from map
Geographic resolution:outcrop
Time
Period: Permian Epoch: Cisuralian
Stage: Artinskian 10 m.y. bin: Permian 2
Key time interval: Artinskian
Age range of interval: 290.1 - 283.5 m.y. ago
Age estimate: 289 ± 0.68 Ma (U/Pb)289 to 286 Ma (U/Pb)
Stratigraphy
Stratigraphic resolution:group of beds
Stratigraphy comments: The deposits occur within karstic deposits formed within bedding planes that were partially dissolved by meteoric dissolution of the Ordovician Arbuckle Limestone. Although long correlated with the Arroyo Formation (Clear Fork Group) of Texas (see Sullivan and Reisz, 1999 p. 1265, for discussion), radioisotopic dating of speleothems by Woodhead et al. (2010) and MacDougall et al. (2017) have provided an older estimate to around 289–286 Ma.
Lithology and environment
Primary lithology:fine,gray poorly lithified claystone
Secondary lithology:coarse conglomerate
Includes fossils?Y
Includes fossils?Y
Lithology description: primarily "fine grey clay... However, sheets of coarse conglomerate occur near the irregular fissure walls, providing evidence for occasional floods... Tetrapod remains occur within both conglomerate and clay"; clay is "largely unlithified" (Sullivan & Reisz, 1999 pp. 1258/59)
Environment:fissure fill Tectonic setting:non-subsiding area
Taphonomy
Modes of preservation:body
Degree of concentration:concentrated
Size of fossils:macrofossils,mesofossils
Spatial orientation:random
Preservation of anatomical detail:variable
Abundance in sediment:abundant
Articulated whole bodies:some
Associated major elements:some
Disassociated major elements:many
Disassociated minor elements:many
Size sorting:medium
Fragmentation:frequent
Encrustation:occasional
Temporal resolution:time-averaged
Collection methods and comments
Collection methods:selective quarrying,surface (float),sieve,field collection,survey of museum collection
Reason for describing collection:taxonomic analysis
Museum repositories:FMNH,MCZ,OU,YPM
Collectors:F. E. Peabody, W. Langston, J. Bolt, E. C. Olson, among others
Collection method comments: The fossils are prepared by "washing the largely unlithified fossiliferous clays and sorting in the laboratory" (Sullivan & Reisz, 1999 p. 1259)
apparently, the material comes from spoil piles produced during commercial quarrying.
Additonal institutions storing material from Richards Spur:
KU(MNH)= KUVP = University of Kansas, Museum of Natural History, Lawrence
ROM = Royal Ontario Musuem, Toronto, Canada
UCLA = University of California Los Angeles
UCMP = University of California Museum of Paleontology, Berkeley
UMMP = University of Michigan Museum of Paleontology, Detroit
USNM = Smithsonian National Museum of Natural History, Washington, DC
UWBM = University of Washington, Burke Museum, Seattle
Taxonomic list comments:Bolt (1969) notes that the clay mound (the "D-concentrate") in the spoil heap of the quarry that contained the type material of Doleserpeton annectens bears the "remains of many thousands of individuals but virtually no genera other than Doleserpeton".
The type specimen of Sillerpeton permianum is said to be UCMP 62480 by Lund (1978 p. 65). This specimen number, however, does not appear among the specimens of Phlegethontia cf. longissima listed by McGinnis (1967 p. 2) but one of these specimens bears the catalogue number UCMP 62580. The latter is listed as referred specimen of S. permianum in Lund (1978 p. 66). Anderson (2002, J. Paleont. 76(6) p. 1031) lists both UCMP 62480 and 62580 as type of S. permianum. Since UCMP 62480 is a braincase according to Lund (1978) and UCMP 62580 is a braincase as well (McGinnis, 1967; Lund, 1978) and since there is only one aistopod braincase present in the Fort Sill material (Anderson, 2002) the type of S. permianum is very likely to be UCMP 62580.
Anderson & Reisz (2003) do not explicitly say when the type of Bolterpeton carrolli was collected but it is improbable that this specimen was known to Bolt in 1980. OMNH 71111 and OMNH 71112, although not explicitly mentioned by Bolt (1980), well may belong to the material that was originally assigned to "species x". Furthermore, Anderson & Reisz (2003) do not explicitly assign the remainder of "species x" to Bolterpeton. Nevertheless they say that these specimens are "closely related" to Bolterpeton, but "because of the size difference between Bolterpeton and Species X, it cannot be said whether Species X is a different species or an ontogenetic variant." Thus, these specimens are re-identified here as ? Bolterpeton sp.
Metadata
Also known as:Fort Sill; OMNH locality V51; Dolese Bros. limestone quarry; FEP 60A
Database number:67862
Authorizer:J. Alroy, G. Lloyd, B. Gee, R. Butler, R. Benson, M. Clapham, J. Mueller Enterer:J. Alroy, T. Liebrecht, R. Benson, R. Butler, M. Clapham, G. Lloyd, B. Gee, E. Dunne
Modifier:B. Gee Research group:paleoentomology,vertebrate
Created:2006-12-13 21:35:34 Last modified:2022-02-27 14:03:27
Access level:the public Released:2006-12-13 21:35:34
Creative Commons license:CC BY
Reference information

Primary reference:
80324. M. J. MacDougall, N. J. Tabor, J. Woodhead, A. R. Daoust, and R. R. Reisz. 2017. The unique preservational environment of the Early Permian (Cisuralian) fossiliferous cave deposits of the Richards Spur locality, Oklahoma. Palaeogeography, Palaeoclimatology, Palaeoecology 475:1-11 [B. Gee/B. Gee]

Secondary references:

59744 J. S. Anderson and J. R. Bolt. 2013. New information on amphibamids (Tetrapoda, Temnospondyli) from Richards Spur (Fort Sill), Oklahoma. Journal of Vertebrate Paleontology 33:553-567 [R. Butler/E. Dunne]
40439 J. S. Anderson and R. R. Reisz. 2003. A new microsaur (Tetrapoda: Lepospondyli) from the Lower Permian of Richards Spur (Fort Sill), Oklahoma. Canadian Journal of Earth Sciences 40(4):499-505 [J. Mueller/T. Liebrecht]
30433 J. S. Anderson, D. Scott, and R. R. Reisz. 2009. Nannaroter mckinziei, a New Ostodolepid ‘Microsaur’ (Tetrapoda, Lepospondyli, Recumbirostra) from the Early Permian of Richards Spur (Ft. Sill), Oklahoma. Journal of Vertebrate Paleontology 29(2):379-388 [J. Mueller/T. Liebrecht]
28686 J. R. Bolt. 1969. Lissamphibian Origins: Possible Protolissamphibian from the Lower Permian of Oklahoma. Science 166:888-891 [J. Mueller/T. Liebrecht]
29097 J. R. Bolt. 1974. A Trematopsid Skull from the Lower Permian, and Analysis of Some Characters of the Dissorophoid (Amphibia: Labyrinthodontia) Otic Notch. Fieldiana: Geology 30(3):67-79 [J. Mueller/T. Liebrecht]
29098 J. R. Bolt. 1977. Cacops (Amphibia: Labyrinthodontia) From the Fort Sill Locality, Lower Permian of Oklahoma. Fieldiana: Geology 37(3):61-73 [J. Mueller/T. Liebrecht]
28699 J. R. Bolt. 1980. New tetrapods with bicuspid teeth from the Fort Sill Locality (Lower Permian, Oklahoma). Neues Jahrbuch für Geologie und Paläontologie, Monatshefte 1980(8):449-459 [J. Mueller/T. Liebrecht]
75576 K. S. Brink, M. J. MacDougall, and R. R. Reisz. 2019. Dimetrodon (Synapsida: Sphenacodontidae) from the cave system at Richards Spur, OK, USA, and a comparison of Early Permian–aged vertebrate paleoassemblages. The Science of Nature 106:2 [B. Gee/B. Gee]
29096 R. L. Carroll. 1968. A ?Diapsid Parietal from the Lower Permian of Oklahoma. Postilla, Peabody Museum of Natural History, Yale University 117:1-7 [J. Mueller/T. Liebrecht]
28692 R. L. Carroll and P. Gaskill. 1978. The Order Microsauria. Memoirs of the American Philosophical Society 126:1-211 [J. Mueller/T. Liebrecht/T. Liebrecht]
75132 M. deBraga, J. J. Bevitt, and R. R. Reisz. 2019. A new captorhinid from the Permian cave system near Richards Spur, Oklahoma, and the taxic diversity of Captorhinus at this locality. Frontiers in Earth Sciences 7:112 [G. Lloyd/G. Lloyd]
32328 D. C. Evans, H. C. Maddin, and R. R. Reisz. 2009. A Re-Evaluation of Sphenacodontid Synapsid Material from the Lower Permian Fissure Fills near Richards Spur, Oklahoma. Palaeontology 52(1):219-227 [J. Mueller/T. Liebrecht]
29090 R. C. Fox. 1962. Two New Pelycosaurs from the Lower Permian of Oklahoma. University of Kansas Publications, Museum of Natural History 12(6):297-307 [J. Mueller/T. Liebrecht]
28784 R. C. Fox and M. C. Bowman. 1966. Osteology and Relationships of Captorhinus aguti (Cope) (Reptilia: Captorhinomorpha). The University of Kansas Paleontological Contributions, Series Vertebrata 11:1-79 [J. Mueller/T. Liebrecht/J. Alroy]
30585 N. B. Fröbisch and R. R. Reisz. 2008. A New Lower Permian Amphibamid (Dissorophoidea, Temnospondyli) from the Fissure Fill Deposits near Richards Spur, Oklahoma. Journal of Vertebrate Paleontology 28(4):1015-1030 [J. Mueller/T. Liebrecht]
75543 B. M. Gee, J. J. Bevitt, and R. R. Reisz. 2019. Dissorophid diversity at the early Permian cave system near Richards Spur, Oklahoma, USA. Palaeontologia Electronica 22(2:a46):1-32 [B. Gee/B. Gee/M. Clapham]
75546 B. M. Gee, J. J. Bevitt, and R. R. Reisz. 2020. Computed tomographic analysis of the cranium of the early Permian recumbirostran ‘microsaur’ Euryodus dalyae reveals new details of the braincase and mandible. Papers in Palaeontology [B. Gee/B. Gee]
75692 B. M. Gee and R. R. Reisz. 2018. Postcrania of large dissorophid temnospondyls from Richards Spur, Oklahoma. Fossil Record 21(1):79-91 [B. Gee/B. Gee]
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