Monographs Details: Palicourea longistipulata subsp. chrysorrhachis (Bremek.) Steyerm.
Authority: Maguire, Bassett. 1972. The botany of the Guayana Highland--part IX. Mem. New York Bot. Gard. 23: 1-832.
Family:Rubiaceae
Discussion:

Palicourea chrysorrhachis Brem., Brittonia 8: 244. 1957.

Palicourea aculeifera Steyerm., Act. Bot. Venez. 2: 331. fig 25. 1967.

The peculiar aculeiform structures within the stipular sheath, a character mentioned by Bremekamp in his description of P. chrysorrhachis, as well as by the present author in his description of P. aculeifera, are likewise found in Psychotria longistipulata and Palicourea sancti-caroli. In the eastern half of its geographical range Palicourea longistipulata has relatively short stipular lobes, mainly lanceolate or narrowly deltoid and relatively shorter, whereas in the southwestern and western portion of its range within the Amazon drainage the stipular lobes are setaceous aristate and relatively longer. However, in Territorio Rondonia, Brazil, both subspecies appear. Although the corolla length generally is longer (11-16 mm) in subsp chrysorrhachis and shorter in subsp longistipulata (9-10 mm), this breaks down in such specimens as Trujillo 3617 (subsp chrysorrachis) with a corolla length of 8-9 mm and in Klug 3424 (subsp longistipulata) with a corolla length of 14-16 mm. There is also variation within the species in length of peduncle and extent of branching of the inflorescence, as well as in the length of the bracts of the inflorescence, these varying from 3-7 mm long to 8-14 mm in Klug 3424.

The fruit which has not been described previously is oval or broadly ovate, 4.5-5 X 3.5-4 mm, 8-ribbed with acute keels on each pyrene with a broad sublunate groove between each rib, and densely tomentose.