Resumo

FARINA, Ángel; ARRIECHE, Dwight; BOADA-SUCRE, Alpidio  e  VELAZQUEZ, Dilia. Anatomía comparada de la lámina foliar de las especies de heliotropium l. (boraginaceae) presentes en venezuela. INCI [online]. 2003, vol.28, n.2, pp.68-74. ISSN 0378-1844.

Summary     The genus Heliotropium is represented in Venezuela by ten species. These species can present problems in taxonomic identification, particularly in the Ortostachys section. In order to detect new characters for their identification, an anatomical study of leaves of Heliotropium species found in this country was performed. The occurrence and localization of crystals resembling cystoliths, the characteristics of the indumentum, the density of stomata and a particular anatomy similar to Kranz in some species, were useful diagnostic characters. The position of crystals resembling cystoliths in the bundle sheath of H. filiforme could be a character not previously used with diagnostic purposes. The occurrence of a bundle sheath with chloroplasts different to those in the rest of the mesophyll in H. fruticosum, H. Purdiei y H. ternatum, could be indicative of a possible C4 metabolism for Carbon uptake. The absence of this character in other species in the same subsection could be the beginning of a taxonomic reconsideration.

Palavras-chave : Anatomía Foliar; Boraginaceae ; Cistolitos ; Heliotropium ; Taxonomía ; Tricomas .