Genus: Archaeodontosaurus BUFFETAUT, 2005
Etymology: Greek, archaios, "ancient," Greek, odous, "tooth," and Greek, sauros, "lizard": Ancient tooth lizard.

Species: descouensi BUFFETAUT, 2005
Etymology: In honor of Dr. Didier Descouensis (Toulouse), thanks to whom the specimen could be acquired by the Toulouse Natural History Museum and was made available for scientific description.

Holotype: MNHDPal 2003-396

Locality: From the vicinity of Ambondromamy, 16°25'S, 47°8'E, a village located in the valley of the Camoro River, about 150 km SW of the coastal town of Mahajanga (Majunga), in the Majunga Basin, Mahajanga Province, Northwestern Madagasar.

Horizon: Isalo IIIB Formation.

Biostratigraphy:

Age: Bathonian Stage, Middle Dogger Epoch, Middle Jurassic.

Material: Incomplete right dentary containing several teeth.