Pollen morphology of some species of Spermacoceae s.s. (Rubiaceae) of the Atlantic Forest, Rio de Janeiro, Brazil

ABSTRACT This work aimed to morphologically characterize 22 species of Spermacoceae s.s found in the Atlantic Forest in the state of Rio de Janeiro with the purpose of improving palynological knowledge of the studied species. The studied species included six species of Borreria and Denscantia cymosa...

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Main Authors: Vania Gonçalves-Esteves, Gabrielle Reboredo Menezes Vieira, Renata Jacomo Paixão de Carvalho, Sonia Regina de Melo Crespo, Claudia Barbieri Ferreira Mendonça
Format: Article
Language:English
Published: Sociedade Botânica do Brasil
Series:Acta Botânica Brasílica
Subjects:
Online Access:http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062020005001201&lng=en&tlng=en
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Summary:ABSTRACT This work aimed to morphologically characterize 22 species of Spermacoceae s.s found in the Atlantic Forest in the state of Rio de Janeiro with the purpose of improving palynological knowledge of the studied species. The studied species included six species of Borreria and Denscantia cymosa, Emmeorhiza umbellata, Hexasepalum apiculatum, H. radula, H. teres, Manettia fimbriata, Mitracarpus eichleri, M. frigidus, M. hirtus, M. lhotzkyanus, M. megapotamicus, Oldenlandia salzmannii, Pentodon pentandrus, Richardia brasiliensis, Richardia scabra and Spermacoce rubescens. Acetolysed pollen grains were analyzed using light (LM) and scanning electron miscroscopy (SEM). The pollen grains varied in size (polar diameter) from medium to large, with the exception of Hexasepalum teres which was very large. Pollen grains were oblate spheroidal in most species, suboblate in six species, prolate spheroidal in Spermacoce rubescens and subprolate in Manettia fimbriata. All pollen grains were colporate, while number of apertures varied (three-19). The endoaperture was lolongate in most species and lalongate in four species. Sexine ornamentation varied among reticulate, reticulate-granulate, microreticulate, granulate with perforation, echinate-perforate and vermiculate. Pollen attributes were found to distinguish the studied species, but do not separate genera, confirming that Spermacoceae is euripolynic.
ISSN:0102-3306
1677-941X