Santos et al. 2020 (Article) Aechmea

Palynotaxonomy of Aechmea subgenus Ortgiesia (Regel) Mez (Bromeliaceae, Bromelioideae)

Author(s):—K.C.C. dos Santos T., R.P. Romanini, M.G.L. Wanderley & C.F.P. da Luz

Publication:—Grana 1-29. (2020) — DOI

Abstract:—The pollen morphology of 16 species of Aechmea subgenus Ortgiesia is characterised, represented by 59 specimens including original data provided for A. kleinii, A. pimenti-velosoi, A. winkleri, Aechmea sp1 and Aechmea sp2. The pollen grains are monads, subisopolar, amb ellipsoidal, slightly flattened/convex in equatorial view, presenting some spheroidal pollen grains at a small percentage, 2(3)-porate, with small to large pores, pore shape circular or elliptic. The exine on the central area of the pollen grain varied from ‘reticulate’ to ‘predominantly microreticulate’ and less frequently from ‘foveolate’ to ‘microreticulate’. Ortgiesia may be considered stenopalynous by the porate aperture pattern and reticulate sculpturing in most cases. However, some secondary details of the exine ornamentation, such as the size variations of the lumina near the pores, as well as the size and shape of the lumina and muri in the central area of the pollen grain, helped to recognise some groups. Multivariate analyses, based on the pollen grain metric variables, similarly grouped species that are morphologically and taxonomically related by their vegetative and reproductive characteristics, such as A. calyculata and A. kleinii, and A. gamosepala and A. cylindrata, while in the remaining species the palynological similarity was less or null, such as in A. blumenavii and A. kertezsiae; A. blumenavii and A. calyculata; A. caudata and A. coelestis; A organensis and A. coelestis, A. gracilis and A. coelestis. Our results allowed an improved morphological characterisation of Ortgiesia and brought to light important data to complement the palynotaxonomy of the subgenus.

Keywords:—Atlantic forest, Brazil, monocots, Poales, pollen morphology, multivariate analyses