The hippocampal formation (HF) is a key structure for learning and long-term memory, which shows highly conserved ontogenetic development and laminar organization throughout mammalian evolution. The aim of this work was to analyze HF development in the plains vizcacha, a native precocial hystricomorph rodent with a ~155-day gestation period. Histological analysis was performed from 40 embryonic days (e.d) up to birth (n=16). Moreover, the adult HF was characterized by immunofluorescence of several markers (n=4). As early as 43 e.d., the hippocampal primordium was identified, including the ventricular, intermediate, hippocampal, and marginal zones. At 58 e.d., the HF evagination positioned the subiculum, hippocampus, and dentate gyrus, coinciding with the beginning of the CA3 pyramidal stratus, which gets mature at 80 e.d. By ~96 e.d., the CA layers gets fully organized similar than adults. All these observations add temporal characteristic to this precocial species. In adults, HF strata displayed a horn architecture, with parvalbumin (PV) GABAergic interneurons scattered in the oriens and radiatum strata, and concentrated in the pyramidal stratum of CA1 and CA3. These interneurons coexpress AMPA glutamate receptor in the pyramidal and oriens strata, and kainate in all the strata. The expression of PV and glutamate receptors in this region suggests their role in synaptic modulation and plasticity, with implications in the social memory and exploration behavior of the vizcacha.