Rubiacearum Americanarum Magna Hama Pars LVI. Overview of the New Group Palicourea sect. Inundatae with Some New Species
Abstract
Many of the species classified in Psychotria L. subg. Heteropsychotria Steyerm. have been shown to belong to Palicourea Aubl. based on morphological and molecular characters. The species studied here belong to a group that was recognized previously as Psychotria ser. Inundatae Müll. Arg., and is treated here as Palicourea sect. Inundatae (Müll. Arg.) C. M. Taylor. This section can be recognized by the combination of leaves without domatia in the abaxial secondary vein axils; distinctive stipules; terminal inflorescences that are not displaced to pseudoaxillary and have a subcapitate to cymose arrangement with regularly well-developed, showy, generally white bracts; subsessile, 4- or 5-merous flowers; a short calyx limb; funnelform or tubular-funnelform, white, thin-textured corollas with the tube not swollen at the base; medium-sized, juicy, black or purple-black fruits; and pyrenes abaxially with four or five broadly angled to narrow ridges and adaxially with a broad concave face or a plane face with a medial furrow that is often broadened inside. The stipules are well developed and have a prominent appendage that is inserted at the base and appears to comprise the entire stipule but actually arises from a short abaxial sheath portion. The 25 species included here range from Belize to Bolivia and southern Brazil, with centers of diversity in the Guayana Highlands region of northeastern South America and the western Amazon basin. The taxonomy of several of these species has been problematic, and they are circumscribed differently here than by previous authors. Plants that have been treated previously in a broadly circumscribed Psy. capitata Ruiz & Pav. are here separated into several different species and none take this epithet, because this name has been misinterpreted and does not apply to any species of this group. A nomenclatural summary, key, and morphological discussions clarify the identities of these names and separation of species of this group. Nine new species and one new subspecies are described here: Pal. aguilarii C. M. Taylor is found in southern Costa Rica and western Panama; Pal. berliniana C. M. Taylor is found in northeastern Peru; Pal. calimana C. M. Taylor is found in western Colombia; Pal. crucifera C. M. Taylor is found in east-central Bolivia; Pal. inundata (Benth.) C. M. Taylor subsp. maynasana C. M. Taylor is found in northeastern Peru; Pal. liesneri C. M. Taylor is found in northeastern South America; Pal. neeana C. M. Taylor is found in eastern Bolivia; Pal. palcazuana C. M. Taylor is found in southeastern Peru; Pal. pampana C. M. Taylor is found in southern Peru and northern Bolivia; and Pal. teranii C. M. Taylor is found in eastern Bolivia. Twelve new sectional, species-level, and infraspecific nomenclatural combinations are made here: Palicourea sect. Inundatae, Pal. albonervia (Standl.) C. M. Taylor, Pal. bracteata (Kuntze) C. M. Taylor, Pal. calochlamys (Standl.) C. M. Taylor, Pal. chlorotica (Müll. Arg.) C. M. Taylor, Pal. guanchezii (Steyerm.) C. M. Taylor, Pal. guarupana (Standl.) C. M. Taylor, Pal. homoplastica (S. Moore) C. M. Taylor, Pal. inundata, Pal. ovatistipula (C. M. Taylor) C. M. Taylor, Pal. roraimensis (Benth.) C. M. Taylor, and Pal. roraimensis subsp. septentrionalis (Steyerm.) C. M. Taylor. Seven names are newly typified here: Psychotria ser. Capitatae Hook. f., Cephaelis guarupana Standl., Pal. cyanea Urb., Psy. chlorotica Müll Arg. var. bahiensis Müll Arg., Psy. chlorotica var. lanceolata Müll. Arg., Psy. chlorotica var. obovata Müll. Arg., and Psy. duckei Standl.
