Micrandra rossiana R.E.Schult.

  • Authority

    Maguire, Bassett. 1967. The botany of the Guayana Highland--Part VII. Mem. New York Bot. Gard. 17: 1-439.

  • Family

    Euphorbiaceae

  • Scientific Name

    Micrandra rossiana R.E.Schult.

  • Description

    Distribution and Ecology - Besides its type locality along the Rio Uaupes, Brazil, and the Rio Negro Colombia, it has been collected in Bolivar, Venezuela, and adjacent British Guiana, at altitudes 400-1000 m, but has not been recorded so far on the Venezuelan side of upper Rio Negro. COLOMBIA. Vaupes: Rio Negro, San Felipe (El Castillo) below confluence rios Guainia and Casiquiare, Jun 1948, Schultes & Lopez 10034 (NY) VENEZUELA. Bolivar: rich rain forest on lower northwestern slopes of Abacapa-tepui, vicinity of camp 1 along Rio Abacapa, alt 420 m, 30-31 Mar 1953, Steyermark 74778 (NY); lower southwest-facing forested slopes of Chimanta-tepui (Torono-tepui) at extreme southern end on north side of Rio Tirica (left hand branch), alt 1000 m, 14 May 1953, Steyermnrk 75343 (NY) ; region de los rios Icabaru, Hacha, alt 450-850 m, 23 Dec 1955-15 Jan 1956, Bernnrdi 2875 (NY) ; orillas de Icabaru, cerca de los saltos al NE del pueblo, alt 450 m, 21 Apr 1957, Bernnrdi 6685 (NY) ; Sierra Ichun, laderas boscosas al norte del Salto Maria Espuna (Salto Ichun), a lo largo del rio Ichun (tributario del rio Paragua), lat 4°46'N, long 63°1S'W, alt 625-725 m, 27 Dec 1961 Steyermark 90218 (NY ). BRITISH GUIANA. Upper Mazaruni River basin, Alt. Ayanganna, infrequent, Dicymbe forest on laterite, below talus from cliffs along NE side, alt 700-800 m, 5 Aug 1960, Tillett, Tillett & Boyan 45050 (fl. only NY).

  • Discussion

    Type. Rio Vaupes, between Ipanore and confluence with Rio Negro, Igarape de Chuva, Taracua, Amazonas, Brazil, 12 Nov 1947, Schultes & Pires 9058 (isotype NY).

    This specimen, No. 45050, lacks hairs in the axils of the side-nerves and if the key is used mechanically it will key out as M. australis, with which it does not seem to be at all related. The leaves are smaller, more rounded and more coriaceous, and the glands at the base are less distinct.

  • Distribution

    Besides its type locality along the Rio Uaupes, Brazil, and the Rio Negro Colombia, it has been collected in Bolivar, Venezuela, and adjacent British Guiana, at altitudes 400-1000 m, but has not been recorded so far on the Venezuelan side of upper Rio Negro.

    Colombia South America| Venezuela South America| Guyana South America|