(A) UMAP visualization of all glutamatergic excitatory neuron subtypes with subclasses labeled. (B) Top: UMAP showing all L6 IT-2 subtypes. Bottom: Expression of subtype markers shared in Catarrhini (≥ 2 species) or specific to marmosets. (C) Top: Enrichment of Gene Ontology (GO) terms in the species-enriched genes from each species, with colors indicating the species. Only the GO terms enriched in at least three species are displayed. Bottom: Expression of the selected species-enriched genes involved in the calcium ion binding and extracellular matrix (ECM). ER, endoplasmic reticulum. (D) Expression of genes with high subclass and human specificity. IT, intratelencephalic; ET, extratelencephalic; NP, near-projecting; CT, corticothalamic.