Different historical backgrounds determine contrasting phylogeographical patterns in two co-distributed Erica species (Ericaceae) across the Strait of Gibraltar

Erica australis and Erica arborea are morphologically and ecologically similar heather species. Erica australis is restricted to the western Mediterranean Basin where it overlaps with the westernmo ...

Strong signature of selection in seeder populations but not in resprouters of the fynbos heathErica coccinea(Ericaceae)

A higher frequency of natural selection is expected in populations of organisms with shorter generation times. In fire-prone ecosystems, populations of seeder plants behave as functionally semelparous populations, with short generation times compared to populations of resprouter plants, which are truly iteroparous. Therefore, a stronger signature of natural selection should be detected in seeder populations, favoured by their shorter generation times and higher rates of population turnover. Here we test this idea in Erica coccinea from the Cape Floristic Region, which is dimorphic for post-fire regeneration mode. We measured three floral traits supposedly subject to natural selection in see…

Riella cossoniana Trab. (Riellaceae, Marchantiophyta) new to France

Riella (Riellaceae, Sphaerocarpales) is a genus of aquatic liverworts with disjunct range in areas of Mediterranean-type climates. Riella has been traditionally subdivided into two subgenera, subgenus Riella, whose plants show smooth or papillose female involucres and Trabutiella, whose plants show winged female involucres. To date only three species of Riella are known in France, all belonging to subgenus Riella. During the course of a study of the plant diversity of temporary brackish ponds in the Camargue area (Southern France), soil sediments were collected from 10 localities and cultivated in the laboratory. From cultures of five of these localities emerged dioicous plants of Riella sh…

From the Strait of Gibraltar to northern Europe: Pleistocene refugia and biogeographic history of heather (Calluna vulgaris, Ericaceae)

Abstract Calluna vulgaris (Ericaceae) is the most widespread and prevalent woody species of the European dry heathland, from the African side of the Strait of Gibraltar to northern Europe. However, previous biogeographic analyses of this species have ignored the western Mediterranean region, despite its preponderant role as a major glacial refugium for European biota. Here, we explore the existence of further Pleistocene glacial refugia for C. vulgaris in the Iberian Peninsula and the Strait of Gibraltar area and provide new insights into the post-glacial colonization of Europe by this emblematic heathland species. We carried out phylogeographical analyses of C. vulgaris samples from 44 loc…

Taxonomic revision of Riella subgenus Trabutiella (Riellaceae, Sphaerocarpales)

The genus Riella (Riellaceae, Sphaerocarpales) includes some 24 species of thalloid aquatic liverworts with unique morphological and ecological features among hepatics. These include the development of sporophytes enclosed within involucres and growing submerged in seasonal fresh or brackish water ponds. Riella subgenus Trabutiella includes species with winged involucres. Seven taxa have been described, however, four to five taxa have been recognized at a time depending on authors. In this study we have conducted a morphological revision of the species of this subgenus, based on 59 traits measured under light and Scanning Electron Microscopy analyses and that were the subject of statistical…

Influence of habitat patchiness on diversity patterns of a habitat specialist plant community

Rediscovery of Riella alatospora (Riellaceae, Sphaerocarpales), an aquatic, South African endemic liverwort previously known from a now largely transformed type locality

7 páginas, 4 figuras.

Characterization of 10 trinucleotide microsatellite loci in the Critically Endangered Pyrenean yam Borderea chouardii (Dioscoreaceae)

The low levels of allozymic variability found in the Critically Endangered Borderea chouardii prompted us to develop microsatellite markers to assess the genetic variability and population structure for the adequate conservation management of this species. A (CTT) n enriched partial genomic library was constructed. Ten polymorphic microsatellite loci were isolated from it, rendering 51 alleles in 47 individuals analysed. The allelic pattern observed for all of the loci with more than two alleles suggests that B. chouardii is tetraploid.

On the verge of extinction: genetics of the critically endangered Iberian plant species, Borderea chouardii (Dioscoreaceae) and implications for conservation management

Borderea chouardii is a relictual and dioecious, strictly sexually reproducing, long-living geophyte of the Dioscoreaceae family. Previous biological and demographic studies have indicated the existence of a uniformly distributed panmictic population of this taxon at the southernmost Spanish pre-Pyrenean mountain ranges where it occurs in rather inaccessible crevices of a single limestone cliff. However, individuals of B. chouardii are spatially subdivided into two subpopulations located, respectively, on the upper and lower parts of the cliff, and vertically separated 150 m. Because of its extreme rarity, B. chouardii was the first Iberian taxon to have a specific conservation plan and has…

Late Cretaceous-Early Eocene origin of yams (Dioscorea, Dioscoreaceae) in the Laurasian Palaearctic and their subsequent Oligocene-Miocene diversification

Aim: Dioscorea (Dioscoreaceae) is a predominantly pantropical genus (< 600 species) that includes the third most important tropical tuber crop and species of pharmacological value. Fossil records from both the Northern and Southern Hemispheres were used to test hypotheses about the origin of the genus Dioscorea, and to examine potential macroevolutionary processes that led to its current distribution. Location: Pantropical distribution. Methods: Divergence times were estimated using the most comprehensive phylogeny of the group published to date based on plastid sequences and fossil calibrations, applying a relaxed-clock model approach. Ancestral areas and range shifts were reconstructed us…

Nunatak survival vs. tabula rasa in the Central Pyrenees: a study on the endemic plant species Borderea pyrenaica (Dioscoreaceae)

14 páginas, 4 figuras, 2 tablas.

Past climate changes facilitated homoploid speciation in three mountain spiny fescues (Festuca, Poaceae)

Apart from the overwhelming cases of allopolyploidization, the impact of speciation through homoploid hybridization is becoming more relevant than previously thought. Much less is known, however, about the impact of climate changes as a driven factor of speciation. To investigate these issues, we selected Festuca picoeuropeana, an hypothetical natural hybrid between the diploid species F. eskia and F. gautieri that occurs in two different mountain ranges (Cantabrian Mountains and Pyrenees) separated by more than 400 km. To unravel the outcomes of this mode of speciation and the impact of climate during speciation we used a multidisciplinary approach combining genome size and chromosome coun…

Riella heliospora (Riellaceae) a new monoicous species of Riella subgenus Trabutiella from California

14 páginas, 8 figuras, 1 tabla.

Floristic distinctiveness and endemic richness of woody plants highlight the biodiversity value of the herriza among all Mediterranean heathlands

Background: Heathlands are relatively abundant in the landscape of the western Mediterranean region, especially in the Strait of Gibraltar region, where it is locally known as herriza. They are ass...

A nuclear Xdh phylogenetic analysis of yams (Dioscorea: Dioscoreaceae) congruent with plastid trees reveals a new Neotropical lineage

New national and regional bryophyte records, 66

a The Natural History Museum, Cromwell Road, London, SW7 5BD, UK; b Department of Plant and Animal Production, Munzur University, Vocational School of Tunceli, Tunceli, Turkey; c International School of Advanced Studies, University of Camerino, Camerino (MC), Italy; d Grupo de Investigación Biología para la Conservación, Universidad Pedagógica y Tecnológica de Colombia, Colombia; e Botanical Survey of India, Central National Herbarium, Howrah, India; f Botanical Garden-Institute, Russian Academy of Science, Vladivostok, Russia; g Viale Rovereto, Trento, Italy; h Department of Botany, Kherson State University, Kherson, Ukraine; i Kherson Branch of Admiral Makarov University, Kherson, Ukraine…

A Complete Description and Conservation Assessment of Riella affinis Howe &amp; Underwood (Riellaceae, Sphaerocarpales) New to Continental Europe

Riella affinis Howe & Underwood is a rare species that is thus far known from eight populations worldwide. Only half of these were recorded in the last 50 years and none were recollected since first reported. Study of a Spanish population of R. cossoniana Trab., recorded in 2002 from Las Lomas, Malaga province, revealed that it belongs to R. affinis. The correct identity of the populations, which had not been available for study, was already suggested by reproductive and ecological characteristics of the plants mentioned in the original publication. The three main lagoons from the Las Lomas endorheic system, where the plants had been recorded, were sampled and living plants of R. affinis we…

Seed germination and seedling allogamy in Rosmarinus officinalis: the costs of inbreeding.

Self‐pollination by geitonogamy is likely in self‐compatible plants that simultaneously expose a large number of flowers to pollinators. However, progeny of these plants is often highly allogamous. Although mechanisms to increase cross‐pollination have been identified and studied, their relative importance has rarely been addressed simultaneously in plant populations. We used Rosmarinus officinalis to explore factors that influence the probability of self‐fertilisation due to geitonogamy or that purge its consequences, focusing on their effects on seed germination and allogamy rate. We experimentally tested the effect of geitonogamy on the proportion of filled seeds and how it influences ge…

New national and regional bryophyte records, 41

WOS: 000348594500007

New national and regional bryophyte records, 48

Andreaea rothii has been recorded for the first time in Croatia. It is a boreo-temperate suboceanic species (Hill et al., 2007) relatively rare in SE Europe, since it is known only from Romania (Ellis et al., 2014d), Slovenia and Serbia (Sabovljevic´ et al., 2008 ; Hodgetts, 2015). The species was found in the Papuk Mountains, situated in the mainly lowland area of NE Croatia. In this region Papuk is the largest and highest mountain range, with peaks between 800 and 900 m a.s.l. They are characterized by high geological diversity dominated by metamorphic rocks, such as different types of schists, as well as granites. The climate is temperate, moderately warm without an explicit dry period. …

Riella bialata Trab. (Riellaceae, Marchantiophyta): A new addition to the European liverwort flora

[EN] Riella (Riellaceae, Sphaerocarpales) is a genus of aquatic liverworts with a disjunct worldwide distribution in areas of seasonal Mediterranean-type climates. Its centre of diversity is located in the Mediterranean basin, where about half the species number of the genus is concentrated. In the course of a worldwide revision of the genus Riella, plants from a monoicous species with wingless, not papillose and smooth involucres were found in two distant Iberian localities. These plants showed a geminate dorsal wing, unlike the single wing occurring in the remaining species of the genus. This character unambiguously assigns these populations to R. bialata, a species known to date from a s…

Advances in the knowledge of South African Riella (Sphaerocarpales) and a new endemic species, Riella trigonospora

Cultures of soil sediments collected in June 2012 from saltpans and vleis from five South African localities have revealed two new, geographically distant, populations of the endemic Riella alatospora, confirmed the presence of Riella purpureospora from Blouvlei in the Cape Town area and uncovered a new endemic species, Riella trigonospora. The new species obtained from cultures from five sampled localities is described and illustrated. It is dioicous and characterised by acuminate to rostrate, papillose involucres and by a unique spore morphology. The spores are dark purple, as in R. purpureospora, and have an irregular discontinuous wing at the equatorial plane, which suggests a morpholog…

An eco-physiological and biotechnological approach to conservation of the world-wide rare and endangered aquatic liverwort Riella helicophylla (Bory et Mont.) Mont.

AbstractThe rare aquatic liverwortRiella helicophylla(Bory et Mont.) Mont., inhabitant of temporary shallow ponds around the Mediterranean basin, is considered threatened throughout its distribution range. In addition, little is known of its biology and ecology or of its role in such an important ecosystem where environmental conditions vary yearly in unpredictable ways. In these variable habitats, due to the seasonal fluctuation of water levels, there is no guarantee of yearly spore input into the spore bank. Spore germination rate and the effects of different culture media in an axenic culture establishment, as well as propagation procedures ofR. helicophylla,were tested. New insights int…

New national and regional bryophyte records, 37

Ellis et al.

Historical and biological determinants of genetic diversity in the highly endemic triploid sea lavender Limonium dufourii (Plumbaginaceae)

14 páginas, 5 figuras, 2 tablas.

Ecological and historical determinants of population genetic structure and diversity in the Mediterranean shrubRosmarinus officinalis(Lamiaceae)

Population genetic studies of widespread Mediterranean shrubs are scarce compared with those of trees and narrow endemics or studies from phylogeographical perspectives, despite the key role these species may play in Mediterranean ecosystems. Knowledge on the effect of ecological factors in shaping their genetic patterns is also limited. In this study we investigate genetic diversity and population structure across 18 populations of Rosmarinus officinalis, a Mediterranean shrubland plant. Populations were sampled along two elevational gradients, one each on calcareous and siliceous soils in a mountain system in the eastern Iberian Peninsula, to decipher the effect of ecological factors on t…

On the synonymization of Acaulon longifolium Herrnst. & Heyn with Acaulon fontiquerianum Casas & Sérgio (Pottiaceae)

During bryological work conducted in the Sharon plane region (Israel), a colony of Acaulon Müll. Hal. was discovered. The plants showed morphological affinities both to A. longifolium Herrnst. & Heyn and A. fontiquerianum Casas & Sérgio depending on the floras used for their identification which challenged their recognition as separate species. In order to solve this taxonomic dilemma, we conducted a detailed morphological characterization of the two species based on representative samples. The micromorphological study of vegetative, sporophytic and spore traits revealed the large overlap of range values between both species. Both species showed the characteristic combination of morphologic…

Study of a New Population of the Argentinian Endemic Species Riella choconensis Hässel (Riellaceae, Marchantiophyta) Reveals a Novel Anatomical Structure of the Female Involucre in Riella

A new population of the Argentinian endemic Riella choconensis Hässel (Riellaceae, Marchantiophyta) was discovered from a culture of sediments from the Laguna de los Juncos (Río Negro province, Argentina). This species was known previously from two nearby collections, made in 1984, in the type locality at the Ramos Mexía reservoir (Neuquén province) and was not recorded since. Fresh material from the new population enabled detailed morphological analyses, which are extensively described here, illustrated and compared to type material of the species. Based on the smooth female involucre, the species belongs to subgenus Riella Mont. However, cross-sections of this structure showed that R. cho…

Data from: Ecological and historical determinants of population genetic structure and diversity in the Mediterranean shrub Rosmarinus officinalis (Lamiaceae)

Population genetic studies of widespread Mediterranean shrubs are scarce compared with those of trees and narrow endemics or studies from phylogeographical perspectives, despite the key role these species may play in Mediterranean ecosystems. Knowledge on the effect of ecological factors in shaping their genetic patterns is also limited. In this study we investigate genetic diversity and population structure across 18 populations of Rosmarinus officinalis, a Mediterranean shrubland plant. Populations were sampled along two elevational gradients, one each on calcareous and siliceous soils in a mountain system in the eastern Iberian Peninsula, to decipher the effect of ecological factors on t…

Floristic distinctiveness and endemic richness of woody plants highlight the biodiversity value of the herriza among all Mediterranean heathlands

Background: Heathlands are relatively abundant in the landscape of the western Mediterranean region, especially in the Strait of Gibraltar region, where it is locally known as herriza. They are associated with a mild Mediterranean climate regime and with acid, nutrient-poor soils. They harbour a high plant diversity, often viewed as a consequence of the transition between European Atlantic heathland and Mediterranean sclerophyllous shrubland floras. Aims: To determine whether species-rich Mediterranean heathlands, including the herriza, constitute distinct heathland formations rather than transitional vegetation units between Atlantic heathlands and Mediterranean garrigue shrublands. Method…