Myrcianthes O.Berg
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Authority
Maguire, Bassett. 1969. The botany of the Guayana Highland-part VIII. Mem. New York Bot. Gard. 18: 1-290.
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Family
Myrtaceae
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Scientific Name
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Description
Distribution and Ecology - VENEZUELA. Bolivar: Northwest slopes of Cerro Venamo, elev 1100-1300 m,14 Apr 1960, Steyermark & Nilsson 137 ( M I C H ) ; above fila La Danta, near km132 between Luepa and Cerro Venamo, elev 1200 m, 18 Apr 1960, Steyermark &Nilsson 297 (MICH).
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Discussion
Eugenia rondonensis Steyerm., Fieldiana Bot. 28: 1013. 1957.
For description see Steyermark, or Fieldiana Bot. 29: 495. 1963. The type, from Mt. Roraima at an elevation of 2000 m or more, Steyermark 58956, is an immature specimen with young buds but no flowers, resembling Myrcianthes fragrans (a primarily West Indian species known also in Venezuela) except that it is almost wholly glabrous; and resembling a similarly glabrous species of northern South America, M . dugandii, except that the peduncles are 3-flowered instead of 7-15-flowered. Most of the leaves in the type of Eugenia rondonensis, moreover, are borne on new and still tender shoots that have elongated rapidly, and it is probable that the larger leaves on this specimen are atypical of ordinary flowering twigs; some of these measure up to 6.5 cm long and 4 cm wide, whereas what I take to be average leaves produced a little later are 4-5.5 cm long and 2.5-3.5 cm wide. The generic position of this type-specimen cannot be determined with absolute certainty from immature buds alone, and as the specimens discussed below suggest another possibility, I prefer not to make any formal nomenclatural transfer based on E. rondonensis until the collection of additional specimens makes it possible to place the plant more precisely.
T w o specimens collected by Steyermark and Nilsson in the vicinity of Cerro Venamo, Bolivar, m a y well represent the same species as the type of Eugenia rondonensis, but as indicated by the structure of the embryo their affinities are with the Pimentinae, not the Eugeniinae. The specimens are not referable to any genus known to me; they bear slightly immature "globose, greenish-yellow to reddish" fruits in 3-flowered dichasia; the calyx-lobes have fallen from all the fruits, but they appear to have been 5 in number; the seeds are 1 or 2 in each fruit, 5 m m long, reniform, with membranous testa and elongate C-shaped embryo. The ovary is bilocular (a feature that is unusual in the Pimentinae), with 5-6 ovules in each locule. The plants are essentially glabrous (like E. rondonensis), with coriaceous leaves 3-5 cm long, 1.5-2.5 c m wide; the peduncles are 2-3 cm long (as against 3-5.5 cm in the type of E. rondonensis). Were it not for the pimentoid embryo, I should refer these collections without much hesitation to E. rondonensis. As the situation now stands, however, I cannot be sure of the generic position of any of the collections, nor that the collection from Roraima is conspecific with those from C. Venamo which are cited below.
The collection cited below may also represent the same taxon as the type of Eugenia rondonensis, but as it bears one broken flower only, I cannot be certain. The 3-flowered dichasium is that of Myrcianthes, and the foliage suggests that of Al. fragrans (leaves obovate, up to 6 c m long, 4 c m wide), but the entire plant is nearly glabrous, and the hypanthium quite glabrous.
V E N E Z U E L A . Bolivar: Chimanta IVIassif, Agparaman-tepui, forested slopes below escarpment, elev 1880-1955 m, 26 Feb 1955 (fl), Steyermark & Wurdack 1152 (MICH).
The following specimen I cannot distinguish from Myrcianthes fragrans (Sw.) McVaugh (Fieldiana Bot. 2 9 : 485. 1963; Myrtus fragrans Sw. Prodr. 79. 1788). Future exploration in northern and northeastern Venezuela m a y show that this species is more abundant in continental South America than is n o w supposed. V E N E Z U E L A . Bolivar: Forest S of El Dorado, elev ca 200 m, 23 Jul 1960 (imm fr), Steyermark 86622 ( M I C H ).
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Distribution
V E N E Z U E L A . Bolivar: Northwest slopes of Cerro Venamo, elev 1100-1300 m,14 Apr 1960, Steyermark & Nilsson 137 ( M I C H ) ; above fila La Danta, near km132 between Luepa and Cerro Venamo, elev 1200 m, 18 Apr 1960, Steyermark &Nilsson 297 (MICH).
Venezuela South America|