Monographs Details: Macrocentrum neblinae Wurdack
Authority: Maguire, Bassett & Wurdack, John J. 1958. The botany of the Guayana Highland--Part III. Mem. New York Bot. Gard. 10: 1-156.
Family:Melastomataceae
Description:Latin Diagnosis - M. longidenti (Gleason) Wurdack valde affinis sed plerumque robustius, foliis maioribus in proportione angustioribus apiee anguste acutis sepalorum lobis interioribus ovatis hebeti-acutis. Herba basi lignosa alt. ad 60 cm superne ramosa, ramis teretibus glabris. Folia opposita in quoque jugo valde dimorphiea primum cum glandulis pallidorubris sparse ornata demum marginibus exceptis glabra; folia minora sessilia ovate acuta ad 8 X 3 mm uninervia margine sparse denticulato-ciliata; folia maiora brevipetiolata (petiolo plerumque ca. 1 mm longo) 2-4 X 0.5-1.3 cm, lanceolata apice acute basi cuneata paulo (0.5-1 mm) triplinervia, marginibus de medio apicem versus sparse denticulatis, denticulis 1-2 mm inter se distantibus uniciliatis cilio appresso. Flores 5-meri solitarii, pedicello ca. 2-3 mm longo, dense glanduloso-puberulo basi bibracteolato bracteolis lanceolatis glabris. Hypanthium (ad torum) 2-2.8 X 2.2-2.7 mm modice glanduloso-puberulum pilis ca. 0.5 mm longis. Calyx vix (0.2 mm) coalitus. lobis interioribus 2-2.5 X 1.6-1.9 mil), ovatis hebeti-acutis sparse glanduloso-puberulis margine glandulosociliolatis, dentibus exterioribus aristatis arista 2-2.5 mm eminenti (in fructu ad 3 mm) basim versus parce glanduloso-scabridula. Petala (paulo immatura) 4.7 X 2.7 mm ovata acuta breviapiculata glabra. Stamina inconspicue dimorphiea; filamenta matura desunt; antherae 2.6 mm longae, basi 0.5 mm latae, paulo subulatae poro 0.2 mm lato, eonnectivo ad insertionem filamenti 0.3 mm producto, appendice dorsali 0.6 mm longa hebetiacuta. Stylus 4.5 X 0.2-0.3 mm; stigma paulo eapitulatum 0.35 mm latum; ovarium 3-loculare glabrum apice in collum breviciliatum 0.5 mm productum ; semina 0.5 X 0.3 mm, laevia pyramidata paulo angulata.

Discussion:

Type: flowers white, locally common on boulders in stream courses in talus forest between Camps 2 and 3, elev. 250-650 m, Cerra de la Neblina, Terr. Amazonas, Venezuela, Dec 22, 1953, Basset Maguire, John J. Wurdack, & George S. Bunting 36802 (NY). Paratype: occasional on and around rocks in forest southeast of Camp 3, elev. 900 m, Cerro de la Neblina, Jan 24, 1954, Maguire, Wurdack, & Bunting 37364.

The leaf-blades of M. long-idem are only 12-17 X 7-9 mm and elliptic or scarcely ovate-elliptic with broadly acute apices; the interior calyx lobes are semi-circular.