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Machaonia brasiliensis (Hoffmanns. ex Humb.) Cham. & Schltdl. Search in The Plant ListSearch in IPNISearch in Australian Plant Name IndexSearch in NYBG Virtual HerbariumSearch in Muséum national d'Histoire naturelleSearch in Type Specimen Register of the U.S. National HerbariumSearch in Virtual Herbaria AustriaSearch in JSTOR Plant ScienceSearch in SEINetSearch in African Plants Database at Geneva Botanical GardenAfrican Plants, Senckenberg Photo GallerySearch in Flora do Brasil 2020Search in Reflora - Virtual HerbariumSearch in Living Collections Decrease font Increase font Restore font
 

Published In: Linnaea 4(1): 2. 1829. (Linnaea) Name publication detailView in BotanicusView in Biodiversity Heritage Library
 

Project Name Data (Last Modified On 8/10/2021)
Acceptance : Accepted
Project Data     (Last Modified On 8/16/2021)
Notes:

This species is characterized by medium-sized leaves; small to well developed lax inflorescences; flowers and fruits that are subsessile; medium-sized (for Machaonia) flowers; and slender, mostly ellipsoid, somewhat well developed fruits. It was additionally characterized by Bacigalupo (1957) as distinguished by appressed, strigillose pubescence on the fruits and sometimes inflorescences axes, but a few specimens are included here that have spreading longer pubescence. It generally lacks spinescent stems, though these are sometimes developed especially at lower nodes. Machaonia brasiliensis is commonly and widely collected, especially in eastern Brazil. Enigmatically, it seems not to have been documented in northern Amazonian Brazil but it is known from southern Venezuela; the Venezuelan plants morphologically match the other plants included in this species, and this apparently disjunction may be an artifact of limited collecting in northern Brazil. 

Machaonia brasiliensis is quite similar to Machaonia acuminata, and some authors have applied this latter name to most of the South American plants (e.g., Delprete, 2010). These two species are both separated here from Machaonia spinosa and Machaonia ottonis based on morphological details, as detailed by Bacigalupo (1957) and Steyermark (1974), and these other two species are here as distinct allopatric species also following Bacigalupo and Steyermark. Machaonia acuminata was based on a Humboldt & Bonpland specimen purported to be from Guayaquil in western Ecuador, a locality withiin the general biogeographic region of Central America and Mexico where this species is well documented. However, no other specimens of Machaonia have been seen in this present review from western Ecuador, so it is possible that this specimen was mislabelled similarly to some other of Humboldt & Bonpland's specimens. If their specimen described as Machaonia acuminata was actually from Venezuela, then this name applies to the widespread South American plants and becomes a synonym of Machaonia brasiliensis while the northern Neotropical plants would take the name Machaonia velutina M. Martens & Galeotti. 

Machaonia brasiliensis is similar to Machaonia spinosa, which is found in the same region, and here considered to differ in its pedicellate flowers and fruits and young fruits that are already narrowly oblanceoloid. These species also generally differ in fruit pubescence, as noted by Bacigalupo, with the fruits usually densely spreading-pilosulous or pilose in Machaonia spinosa, though some specimens have appressed strigose pubescence. These species are rather extensively confused in herbarium annotations, so their allopatry is difficult to assess. The status and systematics of these two species perhaps deserve some re-evaluation that includes field observations, and the possibility of hybridization between them. Machaonia brasiliensis has been included by some authors within the circumscription of Machaonia acuminata, see the discussion of that species for its provisional separation here. 

Hassler and Chodat separated several varieties and forms among the Paraguayan plants of Machaonia brasliensis. These were not clearly diagnosed in their protologues, and thei original material of some of them has not clearly been traced. The material seen that appears to correspond to these infraspecific taxa are not distinguishable within the range of variation now documented in this species in this region, and these infraspecfic taxa are not recognized here. These are synonymized here with Machaonia brasiliensis, but authentic material of two of these has not been seen to compare with Machaonia spinosa. The protologue of their fo. latifolia cited a Balansa collection without a number; this appears to correspond to Balansa 1767. The protologue of their fo. angustifolia cited one specimen, Morong 374a in the Boissier Herbarium, which would seem to be the holotype; however, the collection Hassler 74574 has been annotated in several herbaria by P. Delprete as the lectotype collection of this form, though if this collection is to be treated as the type it would seem to need to be considered a neotype. No particular collection was referenced in the description of var. intermedia, and no collection seems to be curated to correspond to this name, nor to var. vestita

Machaonia williamsii was described based on one specimen from the Río Huallaga valley in central Peru. This is an isolated area, and the plants are poorly documented. The type of this name is quite similar to Machaonia brasiliensis, but differs from most (though not all) plants of that species in its densely villosulous or pilosulous fruits and axes. It is provisionally separated here until it is better known, but may not be distinct. 

Cinchona brasiliensis was described by Humboldt based on a Hoffmannsegg collection, which apparently corresponds to the specimen in Willdenow's herbarium; the protologue has not been seen to confirm this, but the name Humboldt used agrees with the name cited by Roemer & Schultes (5: 13014, 1819) in their treatment. Their name was based on a species name curate on a Hoffmannsegg specimen in the Willdenow herbarium. They gave the locality of Willdenow's Hoffmannsegg collection as "ad ostrium fluminus Amazona circa Gran Para". This collection was later cited, apparently, by Schumann (1889) as the specimen "herb. Willd. 4047". The typification of this name has not been studied in detail, but this Hoffmannsegg specimen would seem to correspond to the type material of Cinchona brasiliensis. Some other sources have cited Sellow s.n. as the type of this name, but Sellow did not travel to Brazil until 1814 so it does not seem likely his collection can be the type of Humboldt's 1807 name. 

Distribution: Lowland gallery forest, riverside and swamp vegetation, southeatern Venzuela (Bolívar), eastern to southeastern Brazil (Bahia, Mato Grosso, Minas Gerais, Pará, Paraná, São Paulo), Paraguay (Alto Paraguay, Amambay, Boquerón, Central, Chaco, Concepción, Cordillera, Itapúa, Ñeembucú, Paraguari, Presidente Hayes), eastern Bolivia (Beni, Santa Cruz), and northern Argentina (Chaco, Corrientes, Formosa, Santa Fe).
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