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

Psychotria megapontica M.-Arg., Mart. Fl. Bras. 6(5): 362. 1881.

Although occupying distinct geographical areas, there appears to be no sharp distinction between the two taxa treated here except the indument on the lower midrib and lateral nerves, subsp colorata possessing puberulence on those parts, whereas subsp megapontica is glabrous throughout. Although subsp colorata has a tendency toward having rather regularly dispersed, elongate, glandular or subuliform squamelliform appendages protruding between the sinuses at the base of the calyx lobes, whereas in subsp megapontica the squamellar processes may be irregularly dispersed, absent, or when present smaller or attached within the base of the calyx tube or below the sinus of the calyx lobes, this character cannot be relied upon in fruiting material when the squamellae usually drop off or disintegrate. Another character noted, but not used to separate these taxa, is that the calyx teeth in subsp colorata appear to be more elongated and lanceolate with an acute to acuminate apex and are entire or only slightly toothed along the margins, whereas in subsp megapontica the calyx lobes tend to be relatively broader, oblong to ligulate-oblong and less elongated with blunter tips and often more irregularly lobed or undulate along the margins.

Psychotria colorata is distinguished from P. rosea, with which it is confused, by the shorter stipular teeth (usually 1-4 mm instead of 6-10 mm long), completely glabrous outer surface of the outermost bracts of the involucre (these usually more or less pubescent in the basal external half of P. rosea), and fewer pairs of lateral nerves of the leaf blades [usually 8-15 each side instead of (11-14-) 16-25 as in P. rosea]. Psychotria colorata, because of its connate outer bracts of the involucre, was placed by Müller-Argoviensis in a different section (11. Tapogomea) than P. rosea, which he considered to belong to section 10. Cephaelis with the outermost bracts either free or only slightly connate at the base. However, although some specimens of P. colorata may show the outermost bracts connate at their base, others are more or less free or split to the base, and there appears to be no definite manner of being able to distinguish the two taxa by their degree of connation.

It would appear that P. rosea and P. colorata are taxa very closely related pertaining to the same group of species as here immediately treated. Likewise, it may be necessary eventually to consider them as subspecies of one larger taxon, as subsp megapontica is treated as a part of P. colorata.