Morphology, anatomy, and taxonomic position of Plocaniophyllon Brandegee (Rubiaceae), a monospecific genus endemic to Mesoamerica
Por:
Martínez-Cabrera D., Terrazas T., Flores H., Ochotorena H.
Publicada:
1 feb 2008
Resumen:
The monospecific genus Plocaniophyllon occurs in mixed forests of Chiapas (Mexico) and San Marcos (Guatemala). Despite the fact that it was described in 1914, it has been poorly collected and consequently it is poorly understood. Here we describe the morphological and anatomical features that characterize Plocaniophyllon flavum Brandegee with the aim to re-evaluate its generic circumscription and tribal placement. We compare the characteristics of this genus with Deppea, with which it has been confused, but also with other genera of the tribe Hamelieae, where both have been classified. Plocaniophyllon shares with the other members of Hamelieae the presence of raphides in all organs; endodermis in the stem; palisade parenchyma formed by one layer of cells, and open spongy parenchyma in the leaf blade; stamens adnate near the corolla base; and seeds with tuberculate micro-ornamentation seed coat. Moreover, veins in Plocaniophyllon have fibers sheathing the phloem cells, with the quaterna
Filiaciones:
Martínez-Cabrera D.:
Programa de Botánica, Colegio de Postgraduados, Montecillo, Estado de México, 56230, Mexico
Terrazas T.:
Univ Nacl Autonoma Mexico, Inst Biol, Dept Bot, Mexico City 04510, DF, Mexico
Flores H.:
Univ Nacl Autonoma Mexico, Inst Biol, Dept Bot, Mexico City 04510, DF, Mexico
Ochotorena H.:
Univ Nacl Autonoma Mexico, Inst Biol, Dept Bot, Mexico City 04510, DF, Mexico
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