First Central American record of Anthracotheriidae (Mammalia, Bothriodontinae) from the early Miocene of Panama

Figures & data

FIGURE 1 Location and biochronology of early Miocene bothriodotines discussed in this study. A, cf. Arretotherium fricki from the early Hemingfordian Cypress Hill Formation in Saskatchewan (Storer and Bryant, 1993); B, A. fricki Macdonald and Shultz, 1956, from the early Hemingfordian Upper Marsland Formation in Nebraska and also present in the Hemingfordian Flint Hill L. F. from South Dakota (Macdonald and Shultz, 1956; Macdonald and Martin, 1987); C, A. leptodus (= Ancodon leptodus) Matthew, 1909, from the early Arikareean Lower Rosebud beds, South Dakota (Scott, 1940; Macdonald, 1956; Macdonald, 1963; Tedford et al., 2004); D, A. acridens Douglass, 1901, from the early Arikarrean Blacktail Deer Creek Fauna., Montana (Hibbard and Keenmon, 1950); E, Kukusepasutanka Macdonald, 1956, from the late Arikareean deposits of Montana (Macdonald, 1956); F, Arretotherium acridens Douglass, 1901, from the early Miocene Toledo Bend L. F., Texas (Albright, 1999); G, A. meridionale, sp. nov., from the Las Cascadas fossil assemblage, Panama. Chronostratigraphy and biochronology modified from Albright et al. (2008). Abbreviations: Ar, Arikareean Faunal Zone; E, early; L, late; L. F., Local Fauna.

FIGURE 2 Location and stratigraphic position of fossil bothriodontines from the Gaillard Cut, Panama Canal area. A, map of North and Central America showing the location of the Panama Canal area and the Gaillard Cut. B, stratigraphic position of the Las Cascadas fossil assemblage and the Centenario Fauna. Modified from Kirby et al. (2008), MacFadden et al. (2010), and Montes et al. (2012).

FIGURE 3 Diagram showing most of the dental cusp nomenclature applied to lower permanent dentitions of anthracotheres in this study. Abbreviations: dlmtc^id , distolingal metacristid; Ent^d , entoconid; Hyp^d , hypoconid; Hyp^ulid , hypoconulid; mletc^id , mesiolingual entoconid; mlmtc^id , mesiolingual metacristid; Met^d , metaconid; poetc^id , postentoconulid; pohyp^id , posthypoconid; pomet^id , postmetacristid; poptc^id , postprotocristid; peetc^id , preentocristid; pehyp^id , prehypocristid; pemtc^id , premetacristid; peptc^id , preprotocristid; Ptc^d , protoconid. Modified from Lihoreau and Ducrocq (2007).

FIGURE 4 Lower dentition of Arretotherium meridionale, sp. nov. A, UF 244187, juvenile left dentary with left dc1, partially erupted left canine, p1, dp2–dp4, m1–m2, and associated right i1–i2 and mandibular symphysis, occlusal view; B, lingual view; C, labial view; D, associated right i1, lingual view; E, labial view; F, associated right i2, lingual view; G, labial view; H, detailed view of the anterior part of UF 244187 showing the erupting Lc1. Abbreviations: pehyp^id , prehypocristid; postlgF, posterolingual furrow; antlgF, anterolingual furrow.

FIGURE 5 Detailed view of the lower permanent dentition of Arretotherium meridionale, sp. nov. A, UF 244187, left m1–m2, lingual view; B, occlusal view; C, X-ray detailed image of the anterior part of UF 244187 showing the erupting permanent Lc1. Abbreviations: pehyp^id , prehypocristid; mlmtc^id , mesiolingual metacristid; peetc^id , preentocristid; pomet^id , postmetacristid; hyp^ulid , hypoconulid.

TABLE 1 Summary of dental measurements (in mm) of A. meridionale, sp. nov., from the Las Cascadas Formation.

Tooth position	MDL	LLL	APL	TW
Ri1	13.06	9.01	—	—
Ri2	15.70	8.99	—	—
Lp1	—	—	10.08	5.93
Ldp2	—	—	17.04	7.91
Ldp3	—	—	22.05	8.90
Ldp4	—	—	31.25	14.13
Lm1	—	—	26.90	18.25
Lm2	—	—	31.76	19.74
LIx	15.07	9.41	—	—
LC1, partial	—	—	25.33	14.84
LM3	—	—	28.55	30.25
Abbreviations: MDL, mesiodistal length; APL, anterior–posterior length; LLL, labiolingual width; TW, transversal width.

FIGURE 6 Upper dentition of Arretotherium meridionale, sp. nov. A, UF 244295, left upper canine, lingual view; B, occlusal view; C, UF 245609, right upper incisor (Ix), labial view; D, lingual view; E, UF 244174, partial left M3, occlusal view.

TABLE 2 Summary table of the anterior–posterior length (APL) and maximum transverse width (MTW) of m1 and M3 for relevant specimens of Arretotherium.

Taxon	Biostratigraphic/lithostratigraphic unit	Tooth position	Catalog number	APL (mm)	MTW (mm)
A. acridens	Toledo Bend L. F. (Texas)	Rm1	LSUMG V-2270	19.6	12.5
A. acridens	Toledo Bend L. F. (Texas)	Lm1	LSUMG V-2347	19.1	12.65
A. fricki	Flint Hill L. F. (South Dakota)	Lm1	SDSM 53440	19.8	11.3
A. meridionale, sp. nov.	Las Cascadas fossil assemblage (Panama)	Lm1	UF 244187	26.53	18.1
A. fricki	Flint Hill L. F. (South Dakota)	Lm1	SDSM 6826	20.3	11
A. fricki	Flint Hill L. F. (South Dakota)	Rm1	UCMP 32373	18.2	10.5
A. acridens	Toledo Bend L. F. (Texas)	RM3	LSUMG V-2366	28.10	26.80
A. acridens	Toledo Bend L. F. (Texas)	LM3	LSUMG V-2367	26.50	26.20
A. acridens	Toledo Bend L. F. (Texas)	LM3	LSUMG V-2365	27.50	26.50
A. acridens	Blacktail Deer Creek Fauna (Montana)	M3	CM 704	28.30	29.40
A. leptodus	Monroe Creek Formation (South Dakota)	RM3	AMNH 13005	24.90	26.60
A. leptodus	Monroe Creek Formation (South Dakota)	LM3	AMNH 13005	25.80	28.70
A. leptodus	Monroe Creek Formation (South Dakota)	RM3	F:AM 132055	27.60	27.00
A. leptodus	Monroe Creek Formation (South Dakota)	LM3	F:AM 132055	27.40	27.00
A. fricki	Flint Hill L. F. (South Dakota)	M3	UNSM 5764	25.70	24.90
A. fricki	Flint Hill L. F. (South Dakota)	RM3	UCMP 32369	25.90	26.10
A. fricki	Flint Hill L. F. (South Dakota)	LM3	UCMP 32369	25.30	24.75
A. fricki	Flint Hill L. F. (South Dakota)	RM3	F:AM 132053	25.50	27.00
A. fricki	Flint Hill L. F. (South Dakota)	LM3	F:AM 132053	25.50	26.90
A. meridionale, sp. nov.	Las Cascadas fossil assemblage (Panama)	LM3	UF 244174	33.29	28.96
Compiled from Douglass (1901), Macdonald (1956), Macdonald and Shultz (1956), Macdonald and Martin (1987), and Albright (1999).

FIGURE 7 Biogeographic distribution and hypothesized phylogenetic relationships (calculated in PAUP 4.0b10) of Anthracotheriidae including Arretotherium meridionale, sp. nov., and A. acridens from the Toledo Bend L. F. (Albright, 1999). Data matrix includes 51 characters and 28 ingroup taxa; Siamotherium krabinese as the outgroup (modified from Lihoreau and Ducrocq, 2007). Pictured here is the strict consensus tree of the six most parsimonious trees resulted from the equally weighted branch-and-bound search (tree length = 120; CI = 0.583, RI = 0.829, HI = 0.41). At each node (bold numbers), the supporting unambiguous synapomorphies are 1, Antracotheriidae (20[1]); 2, Anthracotheriinae (7[1], 19[1]); 3, (18[1], 25[1], 35[1]); 4, (36[1]); 5, (16[1], 34[1], 38[1]); 6, Microbunodontinae (5[1], 6[1], 33[1]); 7, (26[1], 27[1], 32[1], 39[1], 40[1]; 8, (20[0], 37[1]); 9, Bothriodontinae (6[2], 17[1], 23[1], 39[2]); 10, (26[1], 27[1]); 11, (1[2], 2[2], 3[1], 4[2], 14[1], 20[0], 28[1], 44[2]); 12, (17[2], 18[1], 29[1], 35[1]); 13, (4[1], 33[1]); 14, (6[0], 7[1], 8[3], 24[1], 38[2], 39[1]); 15, (12[1]); 16, (20[0], 45[1]); 17, (4[1], 18[0]); 18, (6[1], 24[0]); 19, (11[1], 14[1], 23[0], 35[0], 44[1]); 20, (13[1], 21[1]); 21, (41[1]); 22, (18[0], 28[1]); 23, (39[0]); 24, (17[3], 40[2]); 25, (1[1], 9[2], 10[1], 11[2], 30[1], 31[1], 42[1], 49[1].

Storer , J. E. and Bryant , H. N. 1993 . Biostratigraphy of the Cypress Hills Formation (Eocene to Miocene), Saskatchewan: equid types (Mammalia: Perissodactyla) and associated faunal assemblages . Journal of Paleontology , 67 : 660 – 669 .

 Web of Science ®Google Scholar

Macdonald , J. R. and Shultz , C. B. 1956 . Arretotherium fricki, a new Hemingfordian anthracothere from Nebraska . Bulletin of the University of Nebraska State Museum , 4 : 53 – 58 .

 Google Scholar

Macdonald , J. R. and Martin , J. E. 1987 . “ Arretotherium fricki (Artiodactyla, Anthracotheridae) from the Hemingfordian (Miocene) Flint Hill Local Fauna in South Dakota ” . In Papers in Vertebrate Paleontology in Honor of Morton Greene , Edited by: Martin , J. E. and Ostrander , G. E. 57 – 62 . Dakoterra 3 .

 Google Scholar

Matthew , W. D. 1909 . Observations upon the genus Ancodon . Bulletin of the American Museum of Natural History , 26 : 1 – 7 .

 Google Scholar

Scott , W. B. 1940 . “ Artiodactyla ” . In The Mammalian Fauna of the White River Oligocene , Edited by: Scott , W. B. and Jepsen , G. L. 363 – 746 . Philadelphia : Transactions of the American Philosophical Society . 28, 4, 1–980

 Google Scholar

Macdonald , J. R. 1956 . The North American anthracotheres . Journal of Paleontology , 30 : 615 – 645 .

 Web of Science ®Google Scholar

Macdonald , J. R. 1963 . The Miocene faunas from the Wounded Knee area of western South Dakota . Bulletin of the American Museum of Natural History , 125 : 139 – 238 .

 Google Scholar

Tedford , R. H. , Albright , L. B. III , Barnosky , A. D. , Ferrusquia-Villafranca , I. , Hunt , R. M. Jr. , Storer , J. E. , Swisher , C. C. III , Voorhies , M. R. , Webb , S. D. and Whistler , D. P. 2004 . “ Mammalian biochronology of the Arikareean through Hemphillian interval (late Oligocene through early Pliocene epochs) ” . In Late Cretaceous and Cenozoic Mammals of North America: Biostratigraphy and Geochronology , Edited by: Woodburne , M. O. 169 – 231 . New York : Columbia University Press .

 Google Scholar

Douglass , E. 1901 . Fossil Mammalia of the White River Beds of Montana . Transactions of the American Philosophical Society, New Series , 20 : 237 – 279 .

 Google Scholar

Hibbard , C. W. and Keenmon , K. A . 1950 . New evidence of the Lower Miocene age of the Blacktail Deer Creek Formation in Montana . Contributions from the Museum of Paleontology University of Michigan , 8 : 193 – 204 .

 Google Scholar

Albright , L. B. III. 1999 . Ungulates of the Toledo Bend Local Fauna (late Arikareean, early Miocene), Texas Coastal Plain . Bulletin of the Florida Museum of Natural History , 42 : 1 – 80 .

 Google Scholar

Albright , L. B. III , Woodburne , M. , Fremd , T. , Swisher , C. , MacFadden , B. J. and Scott , G. R. 2008 . Revised chronostratigraphy and biostratigraphy of the John Day Formation (Turtle Cove and Kimberly Members), Oregon, with implications for updated calibration of the Arikareean North American Land Mammal Age . Journal of Geology , 116 : 211 – 327 .

 Web of Science ®Google Scholar

Kirby , M. X. , Jones , D. S. and MacFadden , B. J. 2008 . Lower Miocene stratigraphy along the Panama Canal and its bearing on the Central American peninsula . PLoS ONE , 3 : e2791 doi: 10.1371/journal.pone.0002791.

 PubMed Web of Science ®Google Scholar

MacFadden , B. J. , Kirby , M. , Rincon , A. , Montes , C. , Moron , S. , Strong , N. and Jaramillo , C. 2010 . Extinct peccary “Cynorca” occidentale (Tayassuidae) from the Miocene of Panama and correlations to North America . Journal of Paleontology , 84 : 288 – 298 .

 Web of Science ®Google Scholar

Montes , C. , Cardona , A. , McFadden , R. , Moron , S. E. , Silva , C. A. , Restrepo-Moreno , S. , Ramirez , D. A. , Hoyos , N. , Wilson , J. , Farris , D. , Bayona , G. A. , Jaramillo , C. A. , Valencia , V. , Bryan , J. and Flores , J. A. 2012 . Evidence for middle Eocene and younger emergence in Central Panama: implications for Isthmus closure . Geological Society of America Bulletin , 124 : 780 – 799 . 10.1130/B30528.1

 Web of Science ®Google Scholar

Lihoreau , F. and Ducrocq , S. 2007 . “ Family Anthracotheriidae ” . In The Evolution of Artiodactyls , Edited by: Prothero , D. R. and Foss , S. E. 89 – 105 . Baltimore : The Johns Hopkins University Press .

 Google Scholar