Resumen

GONZALEZ, Ana María  y  ARBO, María Mercedes. Anatomy of some species of Turneraceae. Acta Bot. Venez. [online]. 2005, vol.28, n.2, pp.369-394. ISSN 0084-5906.

The anatomical study of some species of the Venezuelan genera of Turneraceae Piriqueta and Turnera, is presented. The paper includes the analysis of indumentum, colleters, extrafloral nectaries, and the structure of primary stem, wood, leaf, flower and fruit. Material conserved in FAA was used, some species were worked with herborized material. The analysis was made on the basis of optical and scanning electronic microscopy. Glandular trichomes types microcapitate, capitate sessile and setiform were found. The non-glandular trichomes are simple, either unicellular or pluricellular uniseriate and porrect-stellate. The colleters present are standard and sessile types. The extrafloral nectaries can be elevated or flattened. The excretion of the nectar is transcuticular or through "pores". The anatomical characters of the leaves were: epidermal cells, position and type of the stomata, stomatal index, epidermal idioblasts, type of mesophyll, veins and type of bundle sheaths. With these characteristics some species of both genera can be identified. The analysis of the primary and secondary stem does not reveal substantial differences among the analysed species. Original information of the characteristics of this organ is provided. The analysis of the reproductive organs included the anatomy of all the floral pieces. The presence and combination of these characters, in addition to other features like fruit anatomy, allow the characterisation of different taxa in both genera. The fruit surface can be flat, warty or tuberculated, which depends on the structure of the pericarp. Seven pericarp types were observed, two types correspond to flat fruits, and the rest to warty or tuberculated fruits. The results show that certain characters like indument, foliar and fruit anatomy are of greater utility to differentiate the species from the studied genera.

Palabras clave : Turneraceae; Turnera; Piriqueta; Anatomy; Indument; Primary stem; Wood; Leaf; Nectary; Flower; Fruit.