Monographs Details: Psychotria vasivensis (Müll.Arg.) Standl.
Authority: Maguire, Bassett. 1972. The botany of the Guayana Highland--part IX. Mem. New York Bot. Gard. 23: 1-832.
Family:Rubiaceae
Discussion:

Mapouria vasivensis M.-Arg., Flora 59: 460, 466. 1876; Mart. Fl. Bras. 6(5): 409. 1881.

Müller-Argoviensis places this species and Psychotria coussareoides in the section Eumapouria of Mapouria, but in a special series having the inflorescence “anguste thyrsoideae v. subracemi v. subspiciformes.” Müller-Argoviensis did not note the presence in this species of the characteristic elongate, tawny brown fasicles of filiform hairs located at the junction of the axes of the inflorescence with the rachis and at the junction of the axes with the base of the hypanthium. These fascicles of filiform hairs are found also in the following species. Since the original description was based upon fruiting material only, the following description elaborates the flowering state, based upon the specimens cited above: Capitula florum subhemisphaerica 8-15 mm alta 10-20 mm lata 5-20-flora; bracteis sub capitulis conspicuis extimis 3-6 late obovatis vel oblongo-obovatis apice obtusis vel rotundatis 4-9 mm longis 4-6 mm latis manifeste 7-nervatis marginibus ciliolatis extus minute puberulentibus intus glabris; ad junctiones axium et rhachidis necnon ad junctiones axium et basis hy-panthii pilis elongatis filiformibus fasciculatis adsunt; floribus omnino sessilibus sine bracteis singulis; bracteis sub inflorescentia tan turn; calyce hypanthioque 4.5-5 mm longo, hypanthio breviter columnari 1.5 mm longo 1.2-1.5 mm lato glabro; calyce campanulato 3-3.5 mm longo 2.5-3 mm lato irregulariter 5-6-lobato spathaceo, lobis oblongis vel suborbicularibus vel late suborbiculari-triangularibus rotundatis vel subacutis 0.5-1 mm longis 0.5-1.5 mm latis extus puberulentibus; corolla infundibuliformi vel subhypocrateriformi 9-10 mm longa extus omnino glabra heterostyla, tubo 5-5.5 mm longo basi 1.2-1.5 mm lato fauce 3 mm lato intus fauce dense barbato ceterum glabro, lobis quinque lanceolato-oblongis obtusis 4-4.5 × 1.2-1.5 mm apice obtusis appendice incurvata 0.5 mm longa instructis; staminibus exsertis vel inclusis, antheris 1.2-1.8 mm longis; filamentis usque 2-2.5 mm longis; stylo 9.5 mm longo glabro; pyrenis facie ventrali piano dorso valde 5-costatis.