Pitcairnia undulatosepala Rauh[as Pitcairnia undulatosepala Rauh]

Diagnose: —Pitcairniae megasepalorum BAKER (a Costa Rica ad Columbiam) similis, sed ab ea differt characteribus sequentibus: Planta caulescens, nec acaulis, foliatio homomorpha, nec dimorpha. Bracteae scapi internodiis longiores, non breviores. Sepala tantum usque ad 20 mm longa apice uncinata, dua posteriora valde undulato-alata, in P. megasepala tantum alato-carinata et longe acuminata. Ovarium tantum usque 1/2, nec 2/3 vel 4/5 epigynum. Patria et distributio: terricola in sylvis, 2500 m.s.m., Oaxaca-Tehuantepec (Estado Oaxaca, Mexico meridionalis).

Observations: —Similar to P. megasepala Baker,( Costa Rica to Colombia,) but differs from this in following characteristics:
Plant forming a stem, not stemless; Leaves homomorphous not dimorphous. Scape bracts long, not shorter than the internodes. Sepals only to 20 mm long, hooked at the tip, posterior pair strongly undulate winged; but P. megasepala only alate-carinate and long acuminate. Ovary only 1/2, not 2/3 to 4/5 superior.

Pitcairnia undulato-sepala is a quite remarkable species with its undulate-carinate sepals in the subspecies Pitcairnia, that seems close to P. megasepala Baker, from Costa Rica to Panama to Colombia; their sepals are admittedly alate-carinate, but not undulate. Also there are considerable differences between both species that it is considered to be a separate species and up to now , is the only known location.

Edited from : Rauh 1986a. (protologue) Bromelienstudien (Mitteilung 18). I. Neue und wenig bekannte Arten aus Peru und anderen Ländern .