Emma Ortúñez

Anacamptis versus Orchis (Orchidaceae): seed micromorphology and its taxonomic significance

Seed micromorphology of 24 taxa of the genera Anacamptis and Orchis was examined under light and scanning electron microscopy. Seed qualitative characters appear very useful at the supraspecific level in the subtribe Orchidinae. Based on our observations, the sculpturing of the periclinal walls of the medial testa cells, the seed shape and several features of the anticlinal walls of the apical cells showed variability between the studied taxa, with special relevance of the first character. According to this factor, we found one type of seed for Anacamptis and two for Orchis. The taxonomic value of seed coat characters is compared with the last taxonomic proposals for the genera Anacamptis and Orchis.

Epidermal micromorphology of the genus Festuca L. (Poaceae) in the Iberian Peninsula

Micromorphological features of the leaf-blade, lemma, and palea were examined under scanning electron microscopy (SEM) for 64 species of the genus Festuca L. occurring in the Iberian Peninsula. The objective of the study was to survey these characters for the first time in the whole of the genus Festuca in this region, to assess their taxonomic value, and to compare the variation with recent DNA sequence-based phylogenies. The principal features include the frequency, shape, and distribution of silica bodies, short cells, crown cells, and prickles, and the morphology of long cells. The abaxial lemma surface shows the most important taxonomical and phylogenetic characters. The variation observed was consistent with the subgenera and sections identified in molecular studies.

Festuca sect.Eskia (Poaceae) in the Iberian Peninsula

A taxonomical revision of the genusFestuca sect.Eskia in the Iberian Peninsula is presented. Seven species and two hybrid taxa are recognized in this section in the area studied. Karyological data show that six of the studied taxa (F. pseudeskia, F. scariosa, F. elegans subsp.elegans, F. burnatii, F. eskia, andF. ×picoeuropeana) are diploids, two of them are both diploid and tetraploid (F. gautieri andF. quadriflora), one is tetraploid (F. elegans subsp.merinoi) and the ploidy level of one taxon (F. ×souliei) is unknown. A new combinationF. elegans subsp.merinoi (Pau)Fuente etOrtúñez is published. A key based on data collected in this study allows for the identification of all taxa in this section. The complete description of each taxon is presented, as well as the ecology and chorology, including distribution maps. The illustrations summarize plant habits and the morphological and anatomical pattern observed on spikelets, ligules and leaf cross sections. Epidermal features were studied using scanning electron microscopy.

A micromorphological and phylogenetic study of Sarcocornia A.J. Scott (Chenopodiaceae) on the Iberian Peninsula

This study presents a comprehensive revision of the genus Sarcocornia (Chenopodiaceae) on the Iberian Peninsula based on macromorphological, micromorphological and phylogenetic data, and considering caryological, ecological and biogeographical information. Three species of Sarcocornia have been identified on the Iberian Peninsula: Sarcocornia perennis (Miller) A.J. Scott, Sarcocornia fruticosa (L.) A.J. Scott and Sarcocornia alpini (Lag.) Rivas-Martínez. Several authors have proposed that S. alpini is a specific and subspecific rank of S. perennis. Fuente, Rufo and Sánchez-Mata have recently described a new species, Sarcocornia hispanica. The micromorphological and molecular studies (sequence of the internal transcribed spacer region) indicate that there is a broad diversity within Sarcocornia in the Western Mediterranean. This article proposes a new species (Sarcocornia pruinosa) and subspecies (S. alpini subsp. carinata) in view of the new data.

Epidermal micromorphology of the genus Festuca L. subgenus Festuca (Poaceae)

Qualitative and some quantitative micromorphological characters of leaf blades, lemmas and paleas were examined using scanning electron microscopy for 29 species of Festuca subgenus Festuca, including the first observations on members of sections Amphigenes, Dimorphae and Cataphyllophorae. The aim of this study was to survey these features in the subgenus Festuca, to assess their taxonomical value. The observed patterns are compared with current taxonomic proposals based on molecular studies. The characters show important taxonomic value, mainly of the abaxial lemma. Characters showing the greatest variation are shape of long cells, shape of the periclinal walls, thickness of anticlinal walls, presence of prickles and abundance of silica bodies. The principal characters of the leaf-blade surfaces include the type and shape of short cells. Two different surface patterns were observed on the lemma, one, long cells rectangular to elongated, with flat to slightly convex periclinal walls and thickened anticlinal walls, for the sections Amphigenes and Dimorphae, and another, long cells rectangular to square, with concave periclinal walls and unthickened anticlinal walls, for the remaining sections. This study confirms the taxonomic value of micromorphological characters in the subgenus Festuca, and that abaxial lemma surface appears to be the most useful.

On three species of Festuca L. (Poaceae) from the Central Mountain System, Spain.

Abstract Ortúñez, E. & Fuente, V. de la: On three species of Festuca L. (Poaceae) from the Central Mountain System, Spain. — Willdenowia 27: 57–67. 1997. — ISSN 0511-9618. Three Festuca species from Central Spain belonging to the Intravaginales group (Festuca sect. Festuca), i.e. F. rivas-martinezii, F. curvifolia, and F. summilusitana, are studied. The qualitative diagnostic characters are given, and it is demonstrated by means of statistical analyses that the three species are also separated by quantitative characters, particularly the length of the spikelet components and panicle, and the diameter and thickness of the leaf blades. The binomial F. curvifolia is lectotypified and accepted as the correct name for a frequently confused species distributed in the Sierra de Guadarrama and Sierra de Ayllón.

Seed micromorphology of Orchidaceae in the Gulf of Guinea (West Tropical Africa)

Qualitative micromorphological characters of seeds were analysed using Scanning Electron Microscopy for 95 species of 34 genera, belonging to the subfamilies Vanilloideae, Orchidoideae and Epidendroideae (Orchidaceae) from the Gulf of Guinea countries. Three genera (Dinklageella, Platylepis and Rhipidoglossum) and 69 species were studied for the first time. Vanilla shows a pattern of seed coat distinct to the rest of the studied taxa. Orchidoideae and Epidendroideae show variation in several features: seed shape, orientation of testa cells, morphology of anticlinal walls, cell corners, shape and ornamentation of the periclinal walls and presence of waxes. Two main patterns have been observed: one with parallel medial cells along the longitudinal axis, thin and straight anticlinal walls, with no raised and no thickened cell corners, wide periclinal walls and lack of waxes, for the terrestrial orchids of the subfamily Orchidoideae, the tribes Tropidieae, Nervilieae, Collabieae, Cymbidieae and the subtribe Malaxidinae (Epidendroideae); the other one showed twisted medial cells, thickened anticlinal zone with prominent ridges, raised and thickened cell corners, narrow-to-not visible periclinal walls and presence of waxes, in epiphytic orchids of Vandeae, Podochileae and Dendrobiinae (Epidendroideae). In the epiphytic genera Ansellia and Graphorkis (Cymbidieae) and in Liparis epiphytica (Malaxideae), thickened anticlinal walls and presence of waxes also occurred but parallel medial cells along the longitudinal axis and wide periclinal walls have been observed. This study confirms the diagnostic value of the qualitative features of the seed coat in Orchidaceae and suggests a probable relation with adaptations to habitat for seed dispersal.