Genus: Tlayuamichin LOPEZ-ARBARELLO & ALVARADO-ORTEGA, 2011
Etymology: The generic name is written in teh Nahuatl language, which is the language of the Mexica people. The Mexica people inhabited teh area around the Tlayua quarry in prehispanic times. The name Tlayuamichin is formed with the words "tlayua" after the Nahuatal nanme of the fossil locality, and "michin" that means fish.

Species: itztli LOPEZ-ARBARELLO & ALVARADO-ORTEGA, 2011
Etymology: The name of the fish is also written in the Nahuatl language. The species epithte "Itztli" means "obsidian" and in referes to the scale color in the fish. The complete generic and species name of this semionotoid means "the fish of Tlayua with obsidian color scales."

Holotype: IGM 6716

Locality: Tlayua quarry, near the town of Tepexi de Rodriguez, Puebla State, Mexico.

Horizon: Middle Member, Tlayua Formation.

Biostratigraphy:

Age: Middle-Upper Albian Stage, Middle Gallic Subepoch, Late Early Cretaceous Epoch, Late Early Cretaceous.

Material: An almost complete specimen.

Paratypes:

IGM 6717: An almost complete speicmen.

IGM 6718: Specimen missing the head and pectoral girdle.

GIM 6719: Well preserved articutled skull with the anterodorsal portion of body without fins.

IGM 6720: Partially incomplete (the paired fins and part of the unparired fins and squamation are missing) specimen.

IGM.6606: An almost complete specimen.