Monographs Details: Platycarpum maguurei Steyerm.
Authority: Maguire, Bassett & Wurdack, John J. 1964. The botany of the Guayana Highland--Part V. Mem. New York Bot. Gard. 10: 1-278.
Family:Rubiaceae
Description:Latin Diagnosis - Arbor alta ad 25 m, ramulis novellis glabris; stipulis caducis; foliis oppositis coriaceis anguste ellipticis vel elliptico-oblanceolatis apice obtuse acutis vel obtusis basi acutis in petiolum 12-23 mm longum glabrum vel parce adpressopilosum cuneatim angustatis 11-25 mm longis 3-7 cm latis, supra manifeste aspero-scabridulis subtus glauco-pallidis costa media nervis lateralibusque parce strigillosis ceterum venulis minutissime strigillosis vel glabrescentibus, nervis lateralibus utroque latere 15-19 adscendentibus in sicco glauco-purpureis costa media paullo elevatis; petioli una glandula V- vel U-forma 0.6-1 mm lata quoque latere 2-3 mm longo ventraliter inserta; thyrsis terminalibus 10-27-floris 8-15 cm longis 3-8 cm latis 2 1/2-3-plo longioribus quam latioribus pedunculo 1.5-4 cm longo glabro glauco elevatis, ramulis secundariis ferrugineo-hirsutis superioribus 1.5-2 cm longis infimis 3.5-4 cm longis, rhachi in parte inferiore glauca glabra in parte superiore ferrugineo-hirsuta, nodis inferioribus foliis ordinariis vel magnitudine aliquantulo redactis suffultis, ramulis superioribus pedicellisque bracteatis, bracteis subulatis vel linearibus 3-10 mm longis ferrugineo-hirsutis mox caducis; pedicellis 4-13 mm longis dense ferrugineo-hirsutis; calyce 5-mero 10-12.5 mm longo, tubo (hypanthio) campanulato 2.5 mm longo (alto) 6 mm lato cinereo-tomentuloso pilis hirsutis ferrugineis vestito, lobis 5 subaequalibus oblongo-lanceolatis subacutis 9-10 mm longis 3-4 mm latis intus sericeis extus tomentulosis pilis ferrugineis strigosis vestitis; corollis inf undibulif ormibus albis tubo intus rufotincto notato uno lobo luteo (teste Maguire) 26-27 mm longis (in sicco 20-25 mm) extus dense sericeis, tubo 5 mm longo 6 mm lato intus glabro usque 2-3 mm longo fauce dense barbata superne ampliata 9-11 mm longa supra 15-17 mm lata, lobis 5 inaequalibus oblongo-obovatis acutis vel subacutis quatuor 8-14 mm longis 6-8 mm latis 1/3-1/2 longitudinem corollae aequantibus intus glabris quinto 13-17 mm longo 6-8 mm lato intus parte media luteo-pubescenti marginibus glabris exceptis; staminibus 5, duobus paullo brevioribus; staminum antheris lineari-oblongis 3.8-4 mm longis 0.8-0.9 mm latis prominenter apiculatis; filamentis glabris 5-6.5 mm longis; ovario 2.5 mm alto apice hirsutis pilis erectis dense vestito margine corona instructo; stylo 7.5 mm longo glabro ; stigmate 2-fido ovato-oblongo obtuso; capsula ignota.

Distribution and Ecology - Distribution. Extreme southern Venezuela in Territorio Federal Amazonas, where known only from Cerro de la Neblina. VENEZUELA. Amazonas: Cerro Neblina, slope forest between camp 2 and camp 3; alt. 130-700 m; 5 Jan 1958, B. Maguire, C. K. Maguire, Wurdack, & Keith, Jr. 42597 (holotype NY).

Discussion:

Fig. 76, I-J.

This species is most closely related to P. decipiens Woodson & Steyerm. of the Rio Negro-Rio Guainia area, from which it is most readily distinguished by the generally larger corolla with broader, relatively shorter lobes, more spreading rufous pubescence of the upper branches and pedicels of the inflorescence, and relatively narrower inflorescence with shorter lateral branches.