caracterización morfológica y del polen de lathyrus meridensi pittier

Abstract

As a contribution to the knowledge of the palynological flora of Venezuela, the morphological and morphometric characteristics of Lathytus meridensis pollen are described, based on the type specimen and seven exsiccates collected in the Andes of Merida and Trujillo. These samples were examined using an optical microscope and scanning electron microscopy, following the standard methodology. An ACP reduced the structure of the matrix correlating quantitative palynological characteristics to three components, which accounted for 68.75% of the total variance. Pollen grains are 3-zonocolporate, prolate, medium to large-sized (42-55 µm), colpus length (40.13 ± 2.57 µm), colpus width (7.58 ± 1.58 01 µm), the longitudinal axis of the pore (6.39 ± 1.17 µm), cross-axis of the pore (8.57 ± 1.02 µm). These atributes coincide with pollen grains from the Turkish Lathyrus type, but L. meridensis pollen is larger, presenting small, endo-openings, subpsilated apocolpium, rough ornamentation, with well-defined and prominent rugulae in the mesocolpore. The quantitative palynological characteristics of greater diagnostic interest are the colpus length, colpus width, the longitudinal and cross-axis of the pore e, and the mesocolpore width. The exine thickness the does not provide relevant information for the morphometric characterization of Lathyrus type pollen. Ornamentation is the only taxonomically valuable attribute that the exina possesses.