Cytogenetic, Morphometric, and Ecological Characterization of Festuca indigesta Boiss. in the Southeast of Spain.

Festuca indigesta subsp. indigesta (Poaceae) is endemic to the southeast of Spain, and until recently, it was considered that its range of distribution was restricted to the siliceous core of Sierra Nevada. However, it has been recently extended in the territory to others calcareous mountains. This study investigates the cytogenetic variability throughout the geographic range of this taxon, the possible edaphic preferences of each cytotype, and the morphological variation of cytotypes. Genome sizes and ploidy levels were estimated using flow cytometry and chromosome count. Soil samples were collected to test the nature of the substrate, i.e., pH, and calcium and magnesium contents. Finally, morphological characters were measured in herbarium specimens. This study provides the first genome size data for the species. Hidden cytogenetic diversity was detected in the taxon, comprising hexaploid (2n = 6x = 42), octoploid (2n = 8x = 56) and dodecaploid (2n = 12x = 84) individuals. No relationship between substrate nature and cytotype was observed. Morphological differences were detected for the size of floral parts and stomata among cytotypes, but these were blurred if the entire morphological variation range was considered. Our results suggest that each mountain range could act as a reservoir of morphologically cryptic genetic diversity regarding this taxon.

Genome Size, Chromosome Number and Morphological Data Reveal Unexpected Infraspecific Variability in Festuca (Poaceae).

Polyploidy has played an important evolutionary role in the genus Festuca (Poaceae), and several ploidy levels (ranging from 2n = 2x = 14 to 2n = 12x = 84) have been detected to date. This study aimed to estimate the genome size and ploidy level of two subspecies belonging to the F. yvesii polyploid complex by flow cytometry and chromosome counting. The phenotypic variation of the cytotypes was also explored, based on herbarium material. The genome size of F. yvesii subsp. lagascae has been estimated for the first time. Nuclear 2C DNA content of F. yvesii subsp. summilusitana ranged from 21.44 to 31.91 pg, while that of F. yvesii subsp. lagascae was from 13.60 to 22.31 pg. We report the highest ploidy level detected for Festuca (2n = 14x = 98) and previously unknown cytotypes. A positive correlation between holoploid genome size and chromosome number counts shown herein was confirmed. The morphometric approach showed a slight trend towards an increase in the size of some organs consistent with the variation in the ploidy level. Differences in characters were usually significant only among the most extreme cytotypes of each subspecies, but, even in this case, the high overlapping ranges prevent their distinction.

Updated checklist of Poa in the Iberian Peninsula and Balearic Islands.

Based on our study of 4,845 herbarium sheets of the genus Poa from the area covered by Flora iberica, namely, the Iberian Peninsula and the Balearic Islands, we recognise 24 taxa (17 species, 1 subspecies and 8 varieties), mostly perennials. Most of these taxa have wide global and/or European distributions, while two (P. legionensis and P. minor subsp. nevadensis) are Spanish endemics and two have restricted distributions (P. ligulata, Iberia-North Africa; P. flaccidula, Iberia-North Africa and the Balearic Islands, extending to Provence, France). We have studied the original publications of more than 225 names considered as synonyms, with those more historically cited in Flora iberica taken into account in this paper; a total of 26 are new synonyms. The following names are typified: P. alpina var. involucrata Lange, P. annua var. lanuginosa Sennen, P. minor subsp. nevadensis Nannf., P. paui Font Quer, P. sulcata Lag. and P. trivialis var. flaccida Willk. ex J.J. Rodr. We include P. compressa L. in the flora of Portugal for the first time and present detailed illustrations of three very interesting taxa (P. legionensis, P. minor subsp. nevadensis and P. ligulata). In addition to a general species key, we provide the following information for each taxon: synonyms, types, typification, the most relevant iconography, regional flowering time, regional and general distribution and, as supplementary material, the number of sheets examined and a list of selected materials.