Genus: Aristonectes CABREA, 1941
Etymology: Greek, aristos, “superior, best” and Greek, nektes, “swimmer”: Superior swimmer.

Species: parvidens CABREA, 1941
Etymology: Greek, parvus, "petite" and Latin, dens, "tooth."

Holotype: MLP 40-XI-14-6

Locality: Canadon del Loro, middle Chubut River and upstream from Paso del Sapo, western Chubut Province, Patagonia, Argentina.

Horizon: Lefipan Formation (Paso del Sapo Formation).

Biostratigraphy:

Age: Maastrichtian Stage, Upper Senonian Subepoch, Gulf Epoch, Late Cretaceous.

Material: Fragmentary skull and cervical vertebrae.

 

After Otero, Soto-Acuna & O'Keefe, 2018.

Referred material:

O’GORMAN, GASPARINI, & REGUERO, 2010

Locality: Vega Island, Western Antartica.

Horizon: Sandwich Bluff Member, Lopez de Bertodano Formation.

Biostratigraphy:

Age: Maastrichtian Stage, Upper Senonian Subepoch, Gulf Epoch, Late Cretaceous.

Material:

Number: Not given.

 

= Aristonectes cf. parvidens O'GORMAN, GASPARINI, & SALGADO, 2013

Locality: Isla Marambio, 64°13'26.4"S, 56°43'18.3"W, Seymour Island, Antarctica.

Horizon: Lopez de Bertodano Formation.

Biostratigraphy: Unit "klb 9", Pachydiscus ultimus biozone.

Age: Maastrichtian Stage, Upper Senonian Subepoch, Gulf Epoch, Late Cretaceous.

Material:

MLP 89-III-3-2: First pre-pectoral vertebra, 3 pectoral, 4 dorsal vertebrae, left and right coracoid, proximal portion of the left scapula, radius, ulna, radiale, intermedium, ulnare, distal carpal 1, and ribs.

 

Locality: Contralmirante Codero, 38°46'42"S, 68°13'26'4"S, Rio Negro Province, Argentina.

Horizon: Middle Member of the Allen Formation.

Biostratigraphy:

Age: Upper Campanian-Lower Maastrichtian Stage, Upper Senonian Subepoch, Gulf Epoch, Late Cretaceous.

Material:

MUC PV 131: 4 cervical vertebrae, 2 dorsal vertera, a fragment of scapula", tasal or capral element and 4 phalanges.

 

Locality: Salinas de Trapalco, Rio Negro Province, Argentina.

Horizon: Unknow, possibly the Allen Formation.

Biostratigraphy:

Age: Upper Campanian-lower Maastrichtian Stage, Upper Senonian Subepoch, Gulf Epoch, Late Cretaceous.

Material:

MML PV 192: 3 cervical vertebrae.


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Species: quiriquinensis OTERO, SOTO-ACUNA, O'KEEFE, O'GORMAN, STINNESBECK, SUAREZ, RUBILAR-ROGERS, SALAZAR & QUINZIO-SINN, 2014
Etymology: In reference to the Quiriquina Formation, Chile.

Holotype: SGO.PV.957

Locality: Cocholgüe, Biobo Region, Central Chile.

Horizon: Upper Levels, Quiriquina Formation.

Biostratigraphy:

Age: Upper Maastrichtian Stage, Upper Senonian Subepoch, Gulf Epoch, Late Cretaceous.

Material: Skull, atlas-axis, 12 anterior cervical vertebrae, 23 mid-to-posterior cervical vertebrae, most of the trunk, both almost complete forelimbs, and most of the proximal portion of the right hind limb.

Referred material:

SGO.PV.260: A fairly complete postcranial skeleton lacking the skull and half of the neck.

 

= Mauisaurus sp OTERO, SOTO-ACUNA & RUBILAR-ROGERS, 2010 (referred to Aristonectes quiriquinensis by Otero et al, 2015)

Locality: Las Tablas Bay, Quiriquina Island, 73°03'19"S, 36°36'41"W, Biobio Region, Central Chile.

Horizon: Upper Levels, Quiriquina Formation.

Biostratigraphy:

Age: Upper Maastrichtian Stage, Upper Senonian Subepoch, Gulf Epoch, Late Cretaceous.

Material:

SGO.PV.94: Anterior caudal series.

SGO.PV.135: A complete left femur.

SGO.PV.169: A proximal portion of a left humerus.

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