Monographs Details: Phyllanthus major Steyerm.
Authority: Maguire, Bassett. 1967. The botany of the Guayana Highland--Part VII. Mem. New York Bot. Gard. 17: 1-439.
Family:Euphorbiaceae
Description:Distribution and Ecology - Somewhat similar to P. vacciniifolius but goes beyond it in the west. Goes higher in the mountains than P vacciniifolius, between 1000 and 2300 m. Shrub 2-3 m high. Occurs in the Gran Sabana (but not reported from Roraima). Ayanganna of British Guiana and high mountains of the Territorio Amazonas of Venezuela (Duida, Huachamacari, and Serrania Paru). BRITISH GUIANA. Mt. Ayanganna of Chinowieng, alt 1000-1200 m, 7-8 Feb 1955, Maguire, Maguire & Bagshaw 40631-A (NY). VENEZUELA. Bolivar: along streams dwarf forest in flatter area above Fila de la Danta at km 132-132.5 following small stream, between Luepa and Cerro Venamo, alt 1200 m, 18 Apr 1960, Steyermark & Nilsson 287 (NY) ; arbusto frecuente en la 2a altiplanicie pantanosa del Aprada-tepui-Uriman, alt 1400-1500 m, Aug 1953, Bernardi 927 (NY) ; Bonnetia forest, northwestern part of summit of Abacapa-tepui, alt 21252300 m, 13 Apr 1953, Steyermark 74869 (NY, YEN); Chimanta Massif, southwest-facing slopes of Torono-tepui, above valley of Rio Tirica, alt 1000-1700 m, 16 May 1953, Steyermark 75457 (NY, YEN); Chimanta Massif, along base of southeast-facing sandstone bluffs of Torono-tepui, from south corner northeastward, alt 1700 m, 21 May 1953, Steyermark 75529 (NY, YEN); Cerro Venamo (parte Sur-Oeste) cerca de los limites con la Guayana Inglesa, bosque muscoso humedo montanoso a lo largo del afluente derecho (Oeste) subiendo el Rio Venamo, descendiendo el rio desde el campamento cerca de la union con el afluente Este, alt 950-1150 m, 29-30 Dec 1963, Steyermark & Dunsterville 92425 (NY); Amazonas: summit of Mount Duida, alt 5500-6000 ft, 26 Nov-16 Dec 1929, Tate 447 (NY); Cerro Huachamacari, Rio Cunucunuma, frequent, cumbre flora, alt 1700 m, 4 Dec 1950, Maguire, Cowan & Wurdack 29809 (NY); Cerro Huachamacari, Rio Cunucunuma, common, shrub forest, vicinity of Summit Camp, alt 1800 m, 10 Dec 1950, Maguire, Cowan & Wurdack 30104 (NY); Cerro Huachamacari, Rio Cunucunuma, frequent, marshy shrub savanna, southeast escarpment, alt 1900 m, 11 Dec 1950, Maguire, Cowan & Wurdack 30144 (NY); Serrania Paru, Rio Paru, Cano Asisa Rio Ventuari, frequent, west rim, sabanita on Point 1, just N of valley head of camp, alt 2000 m, 31 Jan 1951, Cowan & Wurdack 31065 (NY); Serrania Paru, Rio Paru, Cano Asisa Rio Ventuari, frequent, west rim, cumbre from camp cano to Point 2 (just N of Point 1), alt 2000 m, 31 Jan 1951, Cowan & Wurdack 31109 (NY) ; Serrania Paru, Cano Asisa Rio Ventuari, frequent, cumbre just south of valley head of camp stream, sabanita and scrub forest, alt 2000 m, 2 Feb 1951, Cowan & Wurdack 31140 (NY); Serrania Paru, Rio Paru, Cano Asisa Rio Ventuari, frequent, 6 km along west rim at alt 2000 m, 4 Feb 1951, Cowan & Wurdack 31220 (NY); Cerro Duida, southeastern-facing sandstone bluffs near Cano Negro (tributary of Cano Iguapo), alt 1095-1520 m, on moist exposed cliff face with large bromeliads growing on vertical bluffs at alt 5000 ft, 26 Aug 1944, Steyermark 58035 (NY).

Discussion:

Forested south-facing slopes overlying sandstone, on “Cave Rock” above “Cave Camp.” Ptari-tepui, State of Bolivar, Venezuela, alt 1810 m, 29 Oct 1944, Julian A. Steyermark 59482 (isotype NY).

Phyllanthus major differs from P. vacciniifolius by its larger firmer leaflets and its apiculate but not cuspidate anthers and longer often ribbon like filaments.

Distribution:Guyana South America| Venezuela South America|