Gabriel Blanca

Evaluating riparian vegetation in semi-arid Mediterranean watercourses in the south-eastern Iberian Peninsula

Summary Riparian vegetation is vulnerable to human impact worldwide, and this is especially so in arid areas, yet there have been few quantitative studies and this is especially so in Spain. The state of the riparian vegetation along three major rivers and seasonal watercourses of south-eastern Spain was evaluated during 1992‐93, using the species composition and community structure in watercourses of different sizes under different management. Reaches of the watercourses were classified using five vegetation indices, namely percentage cover, species richness, degree of connectivity between patches of the plant communities, number of exotic species, and evidence of natural regeneration. With the integration of these into one index, the degradation state of the riparian vegetation in each reach was quantified. In addition, types of human activities exerting the greatest impact were noted, and a scale to evaluate the intensity of each impact was established. The indications are that agriculture has very substantially altered the natural vegetation, and this index has served to highlight the most altered zones, and thus those in most urgent need of restoration. Less-degraded zones could serve as models and sources of plant species for future restoration. The degradation index made it possible to establish quickly, easily, and with a high degree of accuracy, the state of conservation of the riparian vegetation in the study area.

Riparian Vegetation and Water Chemistry in a Basin Under Semiarid Mediterranean Climate, Andarax River, Spain

A study has been made of the relationships between the characteristics of the riparian vegetation (floristic composition, structure and diversity) and the spatial–temporal variation of the quality of the stream waters in a basin under a semiarid Mediterranean climate in the southeastern Iberian Peninsula. The plant communities of the high reaches present greater specific richness and diversity (Smean= 7.0 ± 3.4 and H′mean= 2.0 ± 0.7) than do those of the middle and low reaches (Smean= 4.5 ± 1.6 and H′mean= 1.8 ± 0.6). One zone reached the highest specific richness (S= 12, H′= 3.2), which, apart from being situated in the intermediate stretch of the basin, represents a transitional state (ecotone) between the Salix and Tamarix communities. The characteristics of the waters analyzed indicate very high rates of erosion and runoff due to the nature of the soils (easily eroded marls) and to agricultural expansion and mining since the 16th century. The present-day riparian vegetation is not adequate to absorb the nitrates added to the basin by crop fertilization, reaching extremely high values, particularly during the dry period (between 1.2 and 42.5 mg/liter). Sewage dumping at three sampling stations did not appear to affect the specific composition of the woody vegetation. In the zones with watercourses, water salinity was low during the period of greater water flow, but considerably higher in the dry season (the upper limit was some 1.2 mS/m), resulting in a predominance of salt cedars over willows. Three types of saltcedar areas were distinguished: subhalophilous, which barely changes its chemical composition over the season; halophilous, which develops over strongly mineralized waters and markedly alters in chemical composition during the dry season; and hyperhalophilous, where salinity is extraordinarily high and quite constant throughout the year. A direct relationship was found between the dominance of Tamarix africana and abundance of NaCl.

Two new species of the carnivorous genusPinguicula, (Lentibulariaceae) from Mediterranean habitats

Two species ofPinguicula (P. submediterranea andP. mundi) are newly described from the south and east of the Iberian Peninsula. We analysed morphometric, cytogenetic, RAPD, ecological, and breeding system data to support the distinctness of these taxa.Pinguicula submediterranea andP. mundi are both hexaploid (2n = 48), a chromosome number previously not reported for the genus. Biometric, cytogenetical and molecular results distinguishP. submediterranea andP. mundi from otherPinguicula species, and from each other.Pinguicula mundi is predominantly outbreeding, whereasP. submediterranea both inbreeds and outbreeds.Pinguicula submediterranea andP. mundi appear to be isolated reproductively, although gene flow between the allopatricP. submediterranea andP. mundi is unlikely. BothP. submediterranea andP. mundi are threatened with extinction because suitable habitats are diminishing in size, or even disappearing, due to current aridity in the region.

Taxonomic revision of the genusPinguicula L. in the Iberian Peninsula

In this paper, the genusPinguicula is revised in the Iberian Peninsula. The taxa studied areP. vulgaris, P. nevadensis, P. grandiflora subsp.grandiflora, P. dertosensis, P. vallisneriifolia, P. longifolia subsp.longifolia, P. mundi, P. alpina andP. lusitanica. Five taxa are endemic to the area studied (P. nevadensis, P. dertosensis, P. vallisneriifolia, P. longifolia subsp.longifolia andP. mundi). Two of them are confined to restricted areas:P. nevadensis is endemic to the Sierra Nevada (S Spain) andP. longifolia subsp.longifolia is endemic to the central Pyrenees (N Spain). Taxonomical, nomenclatural, morphological, chromosomal, biogeographical and ecological data are reported for each taxon. A new combination is proposed:Pinguicula Sect.Longifolia(Casper) G. Blanca, M. Ruíz-Rejón etR. Zamora.

Evolutionary history of fumitories (subfamily Fumarioideae, Papaveraceae): An old story shaped by the main geological and climatic events in the Northern Hemisphere

Fumitories (subfamily Fumarioideae, Papaveraceae) represent, by their wide mainly northern temperate distribution (also present in South Africa) a suitable plant group to use as a model system for studying biogeographical links between floristic regions of the Northern Hemisphere and also the Southern Hemisphere Cape region. However, the phylogeny of the entire Fumarioideae subfamily is not totally known. In this work, we infer a molecular phylogeny of Fumarioideae, which we use to interpret the biogeographical patterns in the subfamily and to establish biogeographical links between floristic regions, such as those suggested by its different inter- and intra-continental disjunctions. The tribe Hypecoeae is the sister group of tribe Fumarieae, this latter holding a basal grade of monotypic or few-species genera with bisymmetric flowers, and a core group, Core Fumarieae, of more specious rich genera with zygomorphic flowers. The biogeographical analysis shows a subfamily that originated in East Asia at the end of the Early Cretaceous. From here, ancestral range expansions followed three different directions, one at the beginning of the Late Cretaceous by the ancestor of tribe Hypecoeae towards central Asia, and two during the Cretaceous-Palaeogene transition towards western North America and Indochina by the ancestor of the tribe Fumarieae. The ancestor of Core Fumarieae expanded its range from East Asia into the Himalayas before to the middle Eocene. The uplifts of the Qinghai-Tibetan Plateau together with the zonal climate pattern of the Palaeogene are suggested to be responsible both for the accelerated diversification rate resulting in the origin of the basal lineages of Core Fumarieae as well as for the westward migration of the ancestor of Fumarieae s.str. into the Irano-Turanian region. From here, this latter group reached South Africa during late Eocene and Mediterranean basin during Oligocene. There were two colonization waves of the Mediterranean following two different routes: a northern route during the early Oligocene by the subtribe Sarcocapninae, probably facilitated by the land bridge resulting of the Mediterranean microplate accretion; and a southern route into North Africa, through the Gomphotherium land bridge, taken by the subtribe Fumariinae between late Oligocene and middle Miocene.

Phylogeny of the tribe Fumarieae (Papaveraceae s.l.) based on chloroplast and nuclear DNA sequences: Evolutionary and biogeographic implications

PREMISE OF THE STUDY Little research has been done at the molecular level on the tribe Fumarieae (Papaveraceae). Papaveraceae is a model plant group for studying evolutionary patterns despite the lack of a reference phylogeny for this tribe. We investigated the phylogenetic relationships within the tribe to complete the molecular data for this family in order to help understand its character evolution and biogeographic pattern. METHODS We used maximum-parsimony and Bayesian approaches to analyze five DNA regions for 25 species representing 10 of the 11 Fumarieae genera and five outgroups. Evolutionary pathways of four characters (habit, life span, type of fruit, and number of seeds per fruit) were inferred on the phylogeny using parsimony. The ancestral distribution areas were reconstructed using dispersal-vicariance analysis. KEY RESULTS Fumarieae is monophyletic and includes three groups that agree with the morphology-based subtribes: Discocapninae, Fumariinae, and Sarcocapninae. Within subtribes, the relationships among genera were different from those obtained with morphological data. Annual life span, nonchasmophytic habit, and a several-seeded capsule were the basal character states for the tribe. The ancestor occupied a continuous area between West Eurasia and Africa. Vicariances explain the divergence between lineages Discocapninae (South Africa) and Fumariinae-Sarcocapninae (Mediterranean), and the disjunction of Fumariinae (Mediterranean-Central Asia). CONCLUSIONS Molecular phylogeny confirms the subtribal classification of Fumarieae based on morphology. However it provides different results regarding the relationships among genera within each subtribe, which affects the inference of the evolutionary pathway followed by the four selected characters. The disjunct distribution of the tribe is explained by different vicariance scenarios.

Asphodelus tenuifolius andA. fistulosus (Liliaceae) are morphologically, genetically, and biologically different species

The biological analysis of six populations ofAsphodelus tenuifolius and 12 populations ofA. fistulosus has confirmed that they are separate species. Both their floral structures (length of the tepals, stamens, anthers and style) and also their pollen size are clearly different.A. tenuifolius has only the 2n = 28 chromosome race, whileA. fistulosus has 2n = 28 and 2n = 56.A. tenuifolius is genetically less variable thanA. fistulosus and they have different electrophoretic mobilities. Gene duplication phenomena exist in the 2n = 28 level of both species.

Polyploidy, the major speciation mechanism in Muscari subgenus Botryanthus in the Iberian Peninsula

Currently, three species ofMuscari subg. Botryanthus are recognized in the Iberian Peninsula: two diploids (2n = 18), M. atlanticum and M. cazorlanum, and one morphologically variable species with three different ploidy levels, M. neglectum (2n = 36, 45, 54). We have made a comparative study of numerous Iberian populations to clarify the taxonomy and evolution of this group. To this end we carried out morphological and cytogenetic analyses, and phylogenetic analysis of the internal transcribed spacers of nuclear ribosomal DNA. Comparative and UPGMA analyses of the morphological characteristics show that the different ploidy levels of M. neglectum represent different species. We describe the pentaploid and hexaploid levels as two new species, M. olivetorum (2n = 45) and M. baeticum (2n = 54), each with an exclusive combination of morphological characters and a characteristic ecological behavior pattern. Phylogenetic study of ITS shows that the two new species are not autopolyploids from M. neglectum but allopolyploids. These findings are supported by the additivity of the three ITS variants found in M. olivetorum with the ITS of M. neglectum and M. baeticum, and also by morphology. Possible parents for both new species are proposed. Absence of homogenization between homeologous M olivetorum nrDNA loci is explained by the absence of sexual reproduction and by nucleolar dominance, indicating that this is a recent species.

Karyology of theScorzonera (Compositae) species from the Iberian Peninsula

A karyological study of 15 taxa ofScorzonera L. from the Iberian Peninsula has been made. The chromosome numbers found inS. hispanica var.pinnatifida, S. baetica, S. reverchonii, S. angustifolia, S. laciniata var.calcitrapifolia and var.subulata (2n = 14) are new. Diploid cytotypes with 2n = 14 and 2n = 12 prevail, andS. hispanica var.crispatula is the only taxon which exhibits autopolyploidy (2n = 14, 28). x = 7 is considered to be the base chromosome number within the genus, with x = 6 being derived from it by translocation. This and detailed karyotype analyses allow to group the Iberian Peninsula species ofScorzonera into three groups.

Tragopogon lainzii , a New Species of Tragopogon (Asteraceae) Segregated from T. dubius : Evidence from Morphological and Molecular Data

Abstract Tragopogon dubius is one of the most widespread species of Tragopogon, extending across much of Eurasia. Traditionally, T. dubius has been considered a morphologically homogeneous species that includes all Tragopogon collections with yellow flowers and swollen peduncles under capitula. Here we describe a new species of Tragopogon from the Iberian Peninsula, T. lainzii, which has heretofore been included in T. dubius. To this end, we performed comparative morphological, cytogenetic, and molecular analyses on many populations of both species. Our results show that T. dubius is not a homogeneous species and that different lineages exist across its broad geographic distribution. Moreover, we show that hybridization has occurred in the wild between sympatric populations of T. dubius, T. lainzii, and T. porrifolius.