Higher-order mental representations underlying working memory function, are believed to arise in primates, with the development and expansion of the granular prefrontal cortex (PFC). For example, in vivo extracellular recordings from behaving non-human primates (NHPs) have shown that persistent firing representing the contents of working memory can be found in lateral PFC but is absent in early sensory areas such as primary visual (V1) cortex.  However, the mechanistic basis of potentially unique primate PFC circuitry remains speculative, partly due to the lack of data on the biophysical and morphological features of diverse cell-types directly obtained from different brain areas of NHPs. Furthermore, potential differences in PFC single-neuron properties among different NHP species (e.g. new-world monkey Marmoset and old-world monkey Macaque) remain unknown. The latter is an important question, as marmosets are increasingly being used as models for human cognition, yet their cortical microcircuitry is poorly documented. In our international consortium (NeuroNex), we aim to characterize the biophysical and microanatomical properties of cortical neurons from the dorsolateral (DL)PFC and V1 of multiple NHP species (with focus on Callithrix jacchus) using patch clamp electrophysiology in acute brain slices. We systematically collect membrane voltage responses to different characterization protocols and analyzed intrinsic neural properties. To date, we accumulated over 350 intracellular electrophysiological recordings from marmosets. In addition, we examine anatomical features including dendritic type and laminar location of reconstructed neurons. Some of these data can be browsed on the website ‘PrimateDatabase.com’, a collection of publicly available NHP intracellular recordings.