Genus: Mesosaurus GERVAIS, 1864-66
Etymology: Greek, mesos, “middle, intermediate” and Greek, sauros, “lizard”: Intermediate lizard.
= Ditrochosaurus GURICH, 1889
Etymology: Greek, di, “two”, Greek, trokhos, “wheel, round opening" and Greek, sauros, “lizard”: Two opening lizard.
= Ditrichosaurus HUENE, 1956 (sic)

Species: tenuidens GERVAIS, 1864-66
Etymology:

Holotype: MNHN 1865-77

Locality: Griqualand, west Northern Cape Province, South Africa.

Horizon: Whitehill Formation, Ecca Group, Upper Dwyka Shales.

Biostratigraphy:

Age: Kungurian Stage, Uppermost Rotilegendes Epoch, Middle Permian.

Material: Skull and skeleton missing the anterior portion.

GEINITZ

 

Referred material:

AMABILE, 2001

Locality: Itape, 10 km east of Villarrica, 25°47'72"S, 56°48'S, 56°37'W, Guaira Department, Paraguay.

Horizon: Independencia Formation.

Biostratigraphy:

Age: Early Permian.

Material:

Numbers: Not given:

 

MODESTO, 2006, 2010

Locality: Brazil.

Horizon: Irati Formation, Passa Dois Group.

Biostratigraphy:

Age: Kungurian Stage, Uppermost Rotilegendes Epoch, Middle Permian.

Material:

GPIT 1757-2: Vertebral column, ribs, and appendicular elements.

GPIT 1757-3: Dorsal vertebra.

GPIT 1757-4: Sacral rib.

GPIT 1757-5: Isoalted scapulocoracoid.

GPIT T8F34: Partial coracoid.

GPIT T9F32, T9F33: Scapulocoracoids.

GPIT T9F39: Partial forelimb.

GPIT T9F44: Pelvis and femur.

GPIT T9F42:Partial pelvis.

GPIT T9F40: Nearly conmplete pelvis.

GPIT T9F53: Partial skeleton preserving hip region.

GPIT T9F39: Femur, fibula and partial pes.

MCZ 4033: Partial trunk.

GPIT 1757-1: Partial skull of a juvenile.

MCZ 3373: Partial skull, mandibles and articulated presacral column.

MCZ 4028a and counterpart 4028b: Partial skull and cervical series of a large subadult.

MCZ 4030H: Skull, anterior thorax and caudal series.

MCZ 2031a: Partial skull and anterior thorax.

SMNH R202: Nearly complete mandible of a large adult.

SMNH R207a and counterpart R208: Skull of a large individual in right later view.

SMNH R207c: Skull of a large adult.

SMNH R 323: Partial skull of an adult.

Modifed from Modesto, 2006

Locality: South Africa.

Horizon: Whitehill Formation, Ecca Group.

Biostratigraphy:

Age: Kungurian Stage, Uppermost Rotilegendes Epoch, Middle Permian.

Material:

SAM PK-K8381: Part and counterpart of a partial skull with mandible and anteriormost cervical vertebrae.

MNHN 1946-10 15: Partial trunk with gastralia.

SAM-PK-709: Partial skeleton of a small adult..

SAM-PK-9327: Partial skull and mandible, cervical vertebrae, ribs, and pectoral skeleton.

SAM-PK-K8400a: Caudal series posterior to posterior-most rib-bearing caudal.

SAMNH R203b: Skull and anterior thorax of a subadult.

 

PICKFORD, 1995/GROTE, 1984

Locality: Daberas Ost 18, Namibia.

Horizon:

Biostratigraphy:

Age: Early Permian.

Material:

Number: Not given: Disarticulated remains.

 

/SCHREUDER & GENIS, 1975

Locality: White Band at Aussenkjer 147, Namibia.

Horizon:

Biostratigraphy:

Age: Early Permian.

Material:

Number: Not given: Complete skull and skeleton.

 

PINEIRO, RAMOS, GOSO, SCARABINO & LAURIN, 2012,

Locality: Parana Basin, northeastern Uruguay.

Horizon: Mangrullo Formation.

Biostratigraphy:

Age: Kungurian Stage, Uppermost Rotilegendes Epoch, Middle Permian.

Material:

FC-DPV 2254: Skull fragment.

FC-DPV 2104: Skull fragment.

FC-DPV 2462: Palate.

FC-DPV 2518: Fragmentary skeleton.

FC-DPV 2061: Fragmentary skull.

FC-DPV 2109: Fragmentary skull, caudal vertebra and interclavicula.

 

ROSSMANN, 2002

Locality: Piracicaba, Sao Paulo State, Brazil.

Horizon:

Biostratigraphy:

Age: Early Permian.

Material:

PIMUZ A/III 0591: Skull and nearly complete skeleton.

 

SEELEY 1892

Locality: Albania in Griqualand West, west Northern Cape Province, South Africa.

Horizon: Whitehill Formation, Ecca Group, Upper Dwyka Shales.

Biostratigraphy:

Age: Kungurian Stage, Uppermost Rotilegendes Epoch, Middle Permian.

Material:

Number: Not given: Fragmentary skull and fragmentary skeleton.

 


Locality: From near Burghersdorp, Burghersdorp District, East Cape Province, South Africa.

Horizon: Whitehill Formation, Ecca Group, Upper Dwyka Shales.

Biostratigraphy:

Age: Kungurian Stage, Uppermost Rotilegendes Epoch, Middle Permian.

Material:

Albany Museum at Grahmstown: Dorsal vertebrae and ribs.

 

 

= Mesosaurus brasiliensis McGREGOR, 1908
Etymology: In reference to Brazil, country of origin.

Syntypes: (breakdown per HENRIQUES, CARVALHO, & AZEVEDO, 2001)

Locality: Sao Paulo State, Brazil.

Horizon: Irati Formation, Pessa Dois Group.

Biostratigraphy:

Age: Kungurian Stage, Uppermost Rotilegendes Epoch, Middle Permian.

Material:

Museu Nacional/UFRJ MN 1173-V: An almost complete skeleton including skull.

Museu Nacional/UFRJ MN 1174-V: Skull.

Museu Nacional/UFRJ MN 1175-V: Cervical region.

Museu Nacional/UFRJ MN 1177-V: An almost complete skeleton.

Museu Nacional/UFRJ MN 1178-V: An almost complete skeleton.

Museu Nacional/UFRJ MN 1179-V: An incomplete skeleton.

Museu Nacional/UFRJ MN 1192-V: Pelvis.

Referred material:

ROSSMANN, 2000 Mac GREGOR, 1908

SMF-R-386: Skull and skeleton.

SMF-R-387: Skeleton.

SMF-R-388: Skull.

SMF-R-389: Isolated skull.

SMF-R-390: Right and left tarsus.

SMF-R-391: Isolated skull and dorsal vertebrae.

SMF-R-392: Isolated foot.

SMF-R-393: Fragmentary skeleton.

SMF-R-394: Thorax fragment.

SMF-R-395: Fragmentary skeleton.

SMF-R-396: Fragmentary remains.

SMF-R-397: Fragmentary remains.

SMF-R-399: Fragmentary skeleton.

SMF-R-400: Vertebrae.

SMF-R-401: Fragmentary skeleton.

 

ROSSMANN, 2000

Locality: Sao Mateus do Sul, Parana State, South Brazil.

Horizon: Irati Formation, Pessa Dois Group.

Biostratigraphy:

Age: Kungurian Stage, Uppermost Rotilegendes Epoch, Middle Permian.

Material:

SMF-R-4712: Skull and skeleton.

SOARES, 2003

PV0186P, PV0187P, PV0188P, PV0198P, PV0193P, PV0195P, PV0196P, PV0197P, PV0198P, PV0199P, PV0208P, PV0210P, PV0211P, PV0215P, PV0217P, PV0218P, PV0276P, PV0278P, PV0275P, PV0192P, PV0283P, PV0346P, DGM85-R: Articulated specimens.

PV0212P, PV0213P, PV0248P: Isolated bones.

 

Locality: Farm Uitkyk, Calvinia District, Western Cape Province, South Africa.

Horizon: Whitehill Formation, Ecca Group, Upper Dwyka Shales.

Biostratigraphy:

Age: Kungurian Stage, Uppermost Rotilegendes Epoch, Middle Permian.

Material:

SMF-R-4921: Skull and skeleton.

 

FRANCIS, 1975/GUILLEMAIN, 1911

Locality: Canada de los Burros, NE of Melo, Cerro Largo Department, Uruguay.

Horizon: Mangrullo Member, Melo Formation.

Biostratigraphy:

Age: Kungurian Stage, Uppermost Rotilegendes Epoch, Middle Permian.

Material:

Number: Not given: Fragmentary skeleton.

 

HUENE 1940

Locality: Sao Paulo State, Brazil.

Horizon: Irati Formation, Pessa Dois Group.

Biostratigraphy:

Age: Kungurian Stage, Uppermost Rotilegendes Epoch, Middle Permian.

Material:

Number: Not given: Fragmentary skull and fragmentary skeleton.

Stockholm Museum: Fragmentary skull.

HUENE

13 fragmentary skulls and skeletons.

 

ROSSMANN & MAISCH, 1999

Locality: Sao Mateus do Sul, (Steinbruch des Petrobas), Parana State, Brazil.

Horizon: Irati Formation, Pessa Dois Group.

Biostratigraphy:

Age: Kungurian Stage, Uppermost Rotilegendes Epoch, Middle Permian.

Material:

BSP 1972 I 92, BSP 1959 I 477, 1959 I 478, 1949 I 482, 1959 I 360, 1958 I 361: Skulls and skeletons in various degress of preservation.

 

Locality: Sao Gabriel, Rio Grande do Sul State, Brazil.

Horizon: Irati Formation, Pessa Dois Group.

Biostratigraphy:

Age: Kungurian Stage, Uppermost Rotilegendes Epoch, Middle Permian.

Material:

BSP 1967 I 16: 2 skeletons.

 

SHIKAMA

Locality: Sao Paulo State, Brazil.

Horizon: Irati Formation, Pessa Dois Group.

Biostratigraphy:

Age: Kungurian Stage, Uppermost Rotilegendes Epoch, Middle Permian.

Material:

Crown Prince's Palace No. 2942; BUN 662: Fragmentary skeleton.

Crown Prince's Palace No. 2950-1; Bun 663: Fragmentary skeleton.

Crown Prince's Place No. 2950-2; Bun 663: Fragmentary skeleton.

National Science Museum Tokyo, NSMT-P2-4780: Fragmentary skeleton.

 

= Ditrochosaurus capensis GURICH, 1889
Etymology: In reference to Cape Province, South Africa.
= Mesosaurus capensis (GURICH, 1889)

Holotype: BSP 1914 I 504

Locality: Hopetown, Griqualand West, west Northern Cape Province, South Africa.

Horizon: Whitehill Formation, Ecca Group, Kimberley Shales.

Biostratigraphy:

Age: Kungurian Stage, Uppermost Rotilegendes Epoch, Middle Permian.

Material: Fragmentary skeleton.


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Note: There are at least 400 specimens housed in collections in Europe, North and South America, and 170 specimens from Southern Africa.
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