The Neotropical species that have been included in Psychotria L. comprise a heterogeneous group, morphologically and systematically. Carapichea Aubl. (Rubiaceae, Psychotrieae) was separated from Psychotria based on molecular analyses to include C. affinis (Standl.) L. Andersson, C. guianensis Aubl., and C. ipecacuanha (Brot.) L. Andersson; two more species were later included based on morphological characters, C. ligularis (Rudge) Delprete and C. lucida J. G. Jardim & Zappi. Here Carapichea is reviewed morphologically and circumscribed to include 23 Neotropical species found from Nicaragua to southeastern Brazil that share characters of the stipules and inflorescence arrangement. The genus is diagnosed mainly by its distinctive stipules, while pyrene characters, previously considered characteristic for the genus, actually vary widely. A revised morphological description of the genus includes more variation than previously documented, which is outlined in the key to species. Seven informal species groups are separated and characterized, and the following new nomenclatural combinations are made here: Carapichea adinantha (Standl.) C. M. Taylor, based on Retiniphyllum adinanthum Standl. and the sole species of Stachyococcus Standl., which fully synonymizes Stachyococcus with Carapichea; Carapichea altsonii (Sandwith) C. M. Taylor, based on Cephaelis altsonii Sandwith; Carapichea araguariensis (Steyerm.) C. M. Taylor, based on P. araguariensis Steyerm.; Carapichea crebrinervia (Standl.) C. M. Taylor, based on Cephaelis crebrinervia Standl.; Carapichea fimbriflora (Steyerm.) C. M. Taylor, based on P. fimbriflora Steyerm.; Carapichea franquevilleana (Müll. Arg.) C. M. Taylor, based on P. franquevilleana Müll. Arg.; Carapichea klugii (Standl.) C. M. Taylor, based on P. klugii Standl.; Carapichea maturacensis (Steyerm.) C. M. Taylor, based on P. maturacensis Steyerm.; Carapichea necopinata (Standl.) C. M. Taylor, based on P. necopinata Standl.; Carapichea nivea (Sandwith) C. M. Taylor, based on Cephaelis nivea Sandwith; Carapichea pacimonica (Müll. Arg.) C. M. Taylor, based on P. pacimonica Müll. Arg.; Carapichea panurensis (Müll. Arg.) C. M. Taylor, based on Mapouria panurensis Müll. Arg.; Carapichea sandwithiana (Steyerm.) C. M. Taylor, based on Cephaelis sandwithiana Steyerm.; Carapichea tillettii (Steyerm.) C. M. Taylor, based on P. tillettii Steyerm.; Carapichea urniformis (Steyerm.) C. M. Taylor, based on P. urniformis Steyerm.; and Carapichea vasivensis (Müll. Arg.) C. M. Taylor, based on Mapouria vasivensis Müll. Arg. Newly described here is Carapichea verrucosa C. M. Taylor of Amazonian Peru, Colombia, and Brazil, which is notable for its relatively large, abaxially (i.e., dorsally) verrucose pyrenes.