Monographs Details: Psidium guineense Sw.
Authority: Maguire, Bassett. 1969. The botany of the Guayana Highland-part VIII. Mem. New York Bot. Gard. 18: 1-290.
Family:Myrtaceae
Scientific Name:Psidium guineense Sw.
Description:Distribution and Ecology - Venezula. Amazonas: Yavita, elev 128 m, 22 Jan 1942 (fl), Williams 13885(¥). Bolivar: Sabana de Guayapo, Bajo Caura, elev 100 m, 11 Apr 1939 (fl),Williams 11739 (F); comun en la sabana de La Paragua, elev 70 m, 8 Mar 1940(imm fr), Williams 12518 (F); same locality, 9 Mar 1940, Williams 12534 (F);Rio Karaui, base of Sororopan-tepui, W of La Laja, elev 1220 m, 29 Nov 1944 (bud),Steyermark 60777 (F). BRAZIL-VENEZUELA. Frontier between Rio Branco andBolivar, Serra do Sol, Vista Geral, Rio Cotinga, elev 720 m, 11 Dec 1954 (fl), Maguire& Maguire 40214 (MICH). BRITISH GUIANA. Schomburgk 836 (F); Isherton,lat. 2°20' N, basin of Rupununi River, 9-15 Nov 1937 (fl; a nearly glabrous form), A.C. Smith 2500 (NY). BRAZIL. Amapa: Coastal region, Igarape Ariramba, 1°13'N, 51°3' W , 4 Aug 1962 (fl), Pires & Cavalcante 52347 (MICH).

Discussion:

Psidium polycarpon Lambert, Trans. Linn. Soc. 11: 231. pi. 17. 1815.

Psidium dichotomum Weinm., Syll. Ratisb. 2: 166. 1828.

Psidium benthamianum Berg, Linnaea 27: 362. 1856

description and additional synonymy see Fieldiana Bot. 24(7) [Fl. Guatemala]: 394, 1963, or Field Mus. Publ. Bot. 13(4) |F1. Peru]: 796, 1958. Forms of this species, or closely related species that are for all practical purposes indistinguishable, range from Mexico and the West Indies to Argentina. Sometimes cultivated, Psidium guineense is often a shrub of savannas and forest-margins; the fruit is edible but usually smaller and less desirable than that of P guajava.

The type of Psidium guineense is an ample flowering specimen at B M , from the Banks herbarium, labelled "Hispaniola, culta (ex Africa) Dr. Swartz." The type of P. polycarpon, also at B M , is labelled by Lambert "Hort. Boyton A. B. L. 1810." I have seen at W , what is presumably authentic material of P. dichotomum, labelled "ex h. imper. Paulowsk." and "1840"; the type-locality of this latter species was given simply as "in Brasilia," and it was published in an article entitled "Observationes botanicae ex horto Imperiali Pawlowskit'iisi."

The name Psidium benthamianum was based by Berg on "Rob. Schomburgk, coll. no. 836; Rich. Schomb., coh. no. 314," presumably both "in herb. Berol." Berg intended to give a name to the plant which Bentham had mentioned under the name of P polycarpon (Jour. Bot. Hook. 2: 317. 1840); the logical choice of a lectotype would seem to have been no. 836, as Bentham cited no. 636 (although the specimen in his herbarium at K is numbered 836). As the original material of P benthamianum is assumed to have been destroyed, the following is designated as lectotype: Schomburgk 836, annotated by Berg, as P- benthamianum (W; Field Mus. neg. 31418). An authentic paratype is Schomburgk 314, annotated by Berg (K, ex hb. Berol. 1859). Both the paratype and the lectotype are referable to P guineense. The sheet of no. 836 at K e w is a mixture of P guineense with another species of Psidium, and is not annotated by Berg. In the above specimens the buds are incompletely closed, a feature emphasized by Berg in distinguishing his P benthamianum from P polycarpon (= P. guineense).

The following is a very broad-leaved form with 4-angled branchlets and sparingly pubescent herbage, the plants said to have been 20-30 cm high:

V E N E Z U E L A . Bolivar: k m 111 on Puerto Ordaz-Cerro Bolivar railroad, elev 300-350 m, 26 Oct 1953 (imm fr), Maguire et al 36006 (MICH).

Distribution:Venezuela South America| Bolivia South America| Guyana South America|