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Hillieae Bremek. ex S.P. Darwin Search in IPNISearch in NYBG Virtual HerbariumSearch in Flora do Brasil 2020Search in Living Collections Decrease font Increase font Restore font

Published In: Taxon 25(5–6): 603. 1976. (Taxon) Name publication detail

Project Name Data (Last Modified On 12/1/2016)
Acceptance : Accepted
Project Data     (Last Modified On 8/16/2017)

The Neotropical Tribe Hillieae includes three genera and about 30 species of rather succulent shrubs, trees, and epiphytes found in wet vegetation from southern Mexico and the Antilles to Bolivia and Brazil. This tribe is characterized by by raphide crystals in the tissues; a fleshy perennial habit; opposite ligulate, often obtuse to rounded, deciduous stipules that are held flat together and erect in bud and are interpetiolar or shortly fused into a tube; terminal cymose inflorescences or solitary flowers with reduced to developed bracts; 4- to 6-merous showy flowers without calycophylls; well developed corollas with the 4 to 10 lobes imbricated or convolute in bud; and cylindrical, stiff to woody, septicidal capsules with numerous small, flattened, winged seeds. The center of overall species diversity is mainly that of Hillia, in the northern Andes and northern Amazon basin; the center of genus diversity and Cosmibuena's species diversity is in Mexico and Central America. Hillia parasitica is the most widely distributed and commonly collected species; Cosmibuena grandiflora is also rather commonly collected.

The genera of Hilllieae were included for some time in the Tribe Cinchoneae, even though they were anomalous in that group in having raphides, or Hillia was sometimes separated into its own tribe based on its raphides and comose seeds. Andersson (1995) studied Cinchoneae with morphological data and cladistic analyses, and separated the tribe Hillieae with four genera, Hillia, Balmea, Blepharidium, and Cosmibuena. Molecular data later found Blepharidium more closely related to genera of a different tribe, Rondeletieae, than to the other three genera (Rova et al. 2002). Only Hillia and Cosmibuena have been included in molecular analyses, and most analyses inluded only one of them. All three genera were included in the study of Manns & Bremer (2010), who found these genera well supported as a monophyletic group within the subfamily Cinchonoiedeae and recognized this group as Hillieae.

The species of Tribe Hillieae characteristically have rather large showy flowers with apparently distinct pollination syndromes. Hillia and Cosmibuena have nocturnal, sweetly strongly fragrant large salverform white corollas with slender tubes that are presumably pollinated by hawkmoths. Some other species of Hillia have funnelform, diurnal, odorless red flowers that are presumbly pollinated by hummingbirids. And some species of Hillia have broadly funnelform green flowers that are apparently nocturnal and pollinated by bats. The flowers of Balmea are red and funnelform, similarly to some hummingbird-pollinated species of Hillia, but are also reported to be fragrant at night. Some of the species of this tribe are commonly collected, and appear to variously grow as shrubs and trees rooted in soils or as plants anchored on top of rocks or in soil that is constantly saturated, and thus to vary from a terrestrial to epiphytic habit. Other species, in paticular in Hillia, are consistently found as epiphytes.

Species of this tribe are commonly confused with species of Tribe Cinchoneae, which share similar stipules, fruit, and seeds. However speciees of Cinchoneae are erect shrubs and trees without raphides in their tissues. Hillieae are also similar to and easily confused with species of Tribe Schradereae, which has the corolla lobes valvate in bud, fleshy baccate fruits, and involucrate inflorescences.

Author: C.M. Taylor
The content of this web page was last revised on 1 December 2016.
Taylor web page: http://www.mobot.org/MOBOT/Research/curators/taylor.shtml

Distribution: Neotropics: humid vegetation from lowlands to montane areas, southern Mexico and the Antilles to Bolivia and southeastern Brazil.
Taxa Included Here: Genera of Hillieae:
Balmea Martínez
Cosmibuena Ruiz & Pav.
Hillia Jacq.


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 Key to Genera of Tribe Hillieae
by C.M. Taylor

1. Seeds comose, with a tuft of trichomes 5--20 mm long at one end; corolla lobes convolute in bud; flowers solitary or in cymes of 2 or 3.....Hillia

1'. Seeds without a tutf of trichomes; corolla lobes imbricate or convolute in bud; flowers solitary or in cymes of 3 to 25.

     2. Flowers red; corolla lobes convolute in bud and flowers borne in cymes of 5-25 .....Balmea

     2'. Flowers white or flushed with pink; corolla lobes imbricate or convolute in bud, when convolute the flowers solitary....Cosmibuena

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