The Barrancalobian is the first subage of the Marplatan, and is characterized by the Platygonus scagliai biozone. A possible cosmic impact occurred at the start of the Marplatan in Argentina.
Vorohuen
The Vorohuen subage contains the Akodon lorenzinii biozone. The first canids and mustelids of South Americaappear in Vorohuen-age sediments of the Pampas.
Sanandresian
The Sanandresian subage concludes the Marplatan, and coincides with the Ctenomys chapalmalensis biozone. A broadly cold and arid climate began in the Sanandresian, which persisted into the Ensenadan age.