Genus: Aniksosaurus MARTINEZ & NOVAS, 2006
Etymology: Greek, aniksi, "spring," referring to September 21st (i.e. the beginning of the spring in the Southern Hemisphere), the day when the theropod was found, and Greek, sauros, "lizard": Spring lizard.

Species: darwini MARTINEZ & NOVAS, 2006
Etymology: In honor of the great naturalist Charles Darwin, who visited Patagonia in 1832-1833, inspiring him to reach clearer interpretations of the evolution of life that changed human thought forever.

Holotype: MDT-PV 1/48

Locality: Laguna Palacios Ranch, approximately 30 km north of Buen Pasto, 280 km west of Comodoro Rivadavia, in south-central Chubut Province, Argentina.

Horizon: Lower member, Bajo Barreal Formation.

Biostratigraphy:

Age: Early Late Cretaceous.

Material: Articulated right hindlimb including femur, fibula, tibia and foot.

Hypodigm:

MDT-PV 1/1, 1/22, 1/34: 3 left tibae.

MDT-PV 1/2, 1/10, 1/28, 1/44: 4 right tibae.

MDT-PV 1/3, 1/27: 2 right femora.

MDT-PV 1/4, 1/45: 2 indeterminate metatarsi.

MDT-PV 1/5: Right ilium.

MDT-PV 1/6, 1/28: 2 dorsal vertebrae.

MDT-PV 1/7, 1/8, 1/9, 1/15, 1/47, 1/52: 6 indeterminate vertbrae.

MDT-PV 1/11, 1/12, 1/19, 1/20, 1/25, 1/31, 1/38, 1/39: Several indetermiante fragments.

MDT-PV 1/13: Mid-caudal vertebra.

MDT-PV 1/14: Cervical vertebra.

MDT-PV 1/16, 1/36: 2 right humeri.

MDT-PV 1/17: Left ulna.

MDT-PV 1/21, 1/30, 1/46: 3 indeterminate neural archs.

MDT-PV 1/23 (note: with crocodyliforme bite marks, CASAL, MARTINEZ, IBIRICU, GONZALEZ-RIGA, & FOIX, 2013), 1/26: 2 left femora..

MDT-PV 1/24, 1/33, 1/35: 3 left ilia.

MDT-PV 1/29, 1/37, 1/42: 3 left humeri.

MDT-PV 1/32: Proximal caudal vertebra.

MDT-PV 1/40: Manual ungual phalanx.

MDT-PV 1/41: Left ischium.

MDT-PV 1/43: Indeterminate phalanx.