Monographs Details:
Authority:

Maas, Paulus J. M. 1977. Renealmia (Zingiberaceae--Zingiberoideae), Costoideae (Additions) (Zingiberaceae). Fl. Neotrop. Monogr. 18: 1-218. (Published by NYBG Press)
Family:

Zingiberaceae
Synonyms:

Amomum thyrsoideum Ruiz & Pav., Renealmia thyrsoidea, Renealmia geostachys K.Schum., Renealmia platycolea K.Schum., Alpinia thyrsoidea Poepp. & Endl. ex K.Schum., Alpinia silvicola Britton, Renealmia cardenasii Rusby, Renealmia uleana Loes., Renealmia silvicola (Britton) Steyerm. & G.Agostini
Description:

Description - Lamina narrowly elliptic, 20-90 cm long, 5-22 cm wide. Scape 8-80 cm long, the sheaths 3-20 cm long, 0.8-3.5 cm wide. Bracts pinkish to purplish-red, orange-red, or very rarely yellow, rather long persistent or rarely (Trinidad) soon deciduous, 10-50 mm long, 3-35 mm wide. Peduncles 1-2(-5) mm long. Bracteole 5-16(-20) mm long. Pedicels 1-2 mm long, rarely elongating up to 10 mm long. Calyx red to orange-red, 9-17(-23) mm long. Corolla yellow to orange, 19-33 mm long. Labellum yellow to orange, 8-15 mm long and wide. Style 17-26 mm long. Anther 5-12 mm long. Capsule 15-45 X 7-25(-35) mm, 30-75-seeded, aril yellow to red.

Discussion:

Renealmia thyrsoidea is closest to R. dermatopetala. Up to a very late stage of this revision I had divided subspecies thyrsoidea into two other subspecies, one being restricted to the subandean regions and the other to the lowlands. The main differences were in the scape length (somewhat shorter in the subandean form) and in the shape of the bracts (broader in the subandean form). But with every new specimen arriving for study these differences faded away and it proved impossible to maintain these two criteria. Finally I decided to unite the two forms in one subspecies, thyrsoidea.

Renealmia silvicola from Trinidad looks different because of its early deciduous bracts and its relatively long scape. After having studies some recent collections from the nearby Peninsula de Paria in Venezuela, however, it became evident that there are many transitional forms towards this subspecies and thus it proved impossible to maintain R. silvicola.

A still more complex situation was met with during the study of R. geostachys. This species, originally described from lowlands near Leticia, Loreto, Peru, has as characteristics narrow leaves and distinctly reticulate leaf-sheaths (all specimens of this type are marked above with an asterisk). In Colombia (especially in the Sierra de la Macarena region), however, all kinds of intermediate forms between typical thyrsoidea and R. geostachys are found, inducing me to place the latter also in subsp thyrsoidea.

I have not included the characters of Ule 9201 (G, K, MG) from Seringal São Francisco, Acre, Brazil in the description of this subspecies, as that collection is somewhat aberrant by relatively large leaves, a long scape, and yellow bracts.

Maguire et al 37360 (U) from Cerro de la Neblina, Venezuela (1700-2000 m) is related to this subspecies but deviates by very long petioles (to 9 cm long). The leaves very much resemble those of a sterile collection, Prance et al 16140 (INPA, NY, U), from nearby Serra Curicuriari, Amazonas, Brazil. Fortunately living material of the last collection is under cultivation at our greenhouse “Sandwijck” (Utrecht).

Grubb et al 1042 (K) from Cerro Antisana, Ecuador (6000 ft) is related to subsp thyrsoidea, but additional and better material is required before its identity can be ascertained.

In some specimens the floral parts are strongly reduced in size, eg Vargas C.

14661 and 15541; the strongest reduction has taken place in Kuhlmann 2165 (RB) from Ilha de Iquitos, Peru and its floral characters (bracteole 5 mm long; corolla ca 10 mm long; labellum 7 X 7 mm) are not included in the description of the subspecies.

After having studied this very complex R. thyrsoidea subsp thyrsoidea, I am fully aware that the solution of the problem (uniting many species into subsp thyrsoidea) is only a preliminary one. The group can only be fully understood after many field observations in the whole area of its distribution.
Distribution:

Costa Rica South America| Panama Central America| Trinidad and Tobago South America| Colombia South America| Amazonas Colombia South America| Antioquia Colombia South America| Caquetá Colombia South America| Cauca Colombia South America| Chocó Colombia South America| Cundinamarca Colombia South America| Magdalena Colombia South America| Meta Colombia South America| Nariño Colombia South America| Norte de Santander Colombia South America| Putumayo Colombia South America| Santander Colombia South America| Tolima Colombia South America| Valle Colombia South America| Vaupés Colombia South America| Vichada Colombia South America| Venezuela South America| Anzoátegui Venezuela South America| Aragua Venezuela South America| Barinas Venezuela South America| Distrito Federal Venezuela South America| Falcón Venezuela South America| Lara Venezuela South America| Mérida Venezuela South America| Miranda Venezuela South America| Sucre Venezuela South America| Táchira Venezuela South America| Trujillo Venezuela South America| Yaracuy Venezuela South America| Zulia Venezuela South America| Brazil South America| Acre Brazil South America| Amazonas Brazil South America| Ecuador South America| Morona-Santiago Ecuador South America| Napo Ecuador South America| Pastaza Ecuador South America| Santiago-Zamora Ecuador South America| Zamora-Chinchipe Ecuador South America| Peru South America| Amazonas Peru South America| Ayacucho Peru South America| Cusco Peru South America| Huánuco Peru South America| Junín Peru South America| Loreto Peru South America| Madre de Dios Peru South America| San Martín Peru South America| Bolivia South America| Beni Bolivia South America| La Paz Bolivia South America|