Search results for "taxonomy."
showing 10 items of 1110 documents
Towards a phylogenetic classification of Leptothecata (Cnidaria, Hydrozoa)
2016
AbstractLeptothecata are hydrozoans whose hydranths are covered by perisarc and gonophores and whose medusae bear gonads on their radial canals. They develop complex polypoid colonies and exhibit considerable morphological variation among species with respect to growth, defensive structures and mode of development. For instance, several lineages within this order have lost the medusa stage. Depending on the author, traditional taxonomy in hydrozoans may be either polyp- or medusa-oriented. Therefore, the absence of the latter stage in some lineages may lead to very different classification schemes. Molecular data have proved useful in elucidating this taxonomic challenge. We analyzed a supe…
Taxonomic and nomenclatural revision of Carlos Pau’s names in Hieracium (Asteraceae)
2019
During a study on the taxonomy of Hieracium for the Flora iberica project, several names turned out to be not yet typified. In the present paper, 63 names of Hieracium are treated. In order to fix their applications, nomenclatural types for 28 Pau’s names in the genus Hieracium are designated (27 lectotypes, 1 neotype and 1 epitype). All the type material available is listed with full label data, and some nomenclatural and taxonomic comments are provided.
Sareomycetes: more diverse than meets the eye
2021
AbstractSince its resurrection, the resinicolous discomycete genus Sarea has been accepted as containing two species, one with black apothecia and pycnidia, and one with orange. We investigate this hypothesis using three ribosomal (nuITS, nuLSU, mtSSU) regions from and morphological examination of 70 specimens collected primarily in Europe and North America. The results of our analyses support separation of the traditional Sarea difformis s.lat. and Sarea resinae s.lat. into two distinct genera, Sarea and Zythia. Sarea as circumscribed is shown to conservatively comprise three phylospecies, with one corresponding to Sarea difformis s.str. and two, morphologically indistinguishable, correspo…
Morphological and genetic analyses reveal a cryptic species complex in the echinoid Echinocardium cordatum and rule out a stabilizing selection expla…
2014
14 pages; International audience; Preliminary analyses revealed the presence of at least five mitochondrial clades within the widespread sea urchin Echinocardium cordatum (Spatangoida). In this study, we analyzed the genetic (two mitochondrial and two nuclear sequence loci) and morphological characteristics (20 indices) from worldwide samples of this taxon to establish the species limits, morphological diversity and differentiation. Co-occurring spatangoid species were also analyzed with mitochondrial DNA. The nuclear sequences confirm that mitochondrial lineages correspond to true genetic entities and reveal that two clades (named A and B1) hybridize in their sympatry area, although a more…
Patterns of the lemma micromorphology : a useful tool in taxonomy of the middle Asian Eragrostis species (Poaceae)
2017
We examined all taxa of the genus Eragrostis noted so far in Middle Asia, namely: Eragrostis amurensis, Eragrostis cilianensis, Eragrostis minor agg., Eragrostis pilosa and Eragrostis virescens. By means of scanning electron microscope, such structures as long cells, short cells (cork and silica cells), prickles, microhairs and glands were scrutinized and compared among taxa. Additionally, several macromorphological characteristics were investigated. Principal component analysis and cluster analysis were conducted in order to reveal the morphological relationships and differences among species. Micromorphology of the lemma epidermis, together with selected macromorphological characteristics…
Notulae to the Italian flora of algae, bryophytes, fungi and lichens: 7
2019
In this contribution, new data concerning algae, bryophytes, fungi, and lichens of the Italian flora are presented. It includes new records and confirmations for the algae genusChara, the bryophyte generaCephalozia,Conardia,Conocephalum,Didymodon,Sphagnum,Tetraplodon, andTortula, the fungal generaEndophyllum,Gymnosporangium,Microbotryum,Phragmidium, andPluteus, and the lichen generaCandelariella,Cladonia,Flavoplaca,Lichenothelia,Peltigera,Placolecis,Rinodina,Scytinium, andSolenopsora.
The legacy of a vanished sea: a high level of diversification within a European freshwater amphipod species complex driven by 15 My of Paratethys reg…
2016
16 pages; International audience; The formation of continental Europe in the Neogene was due to the regression of the Tethys Ocean and of the Paratethys Sea. The dynamic geology of the area and repetitious transitions between marine and freshwater conditions presented opportunities for the colonization of newly emerging hydrological networks and diversification of aquatic biota. Implementing mitochondrial and nuclear markers in conjunction with a large-scale sampling strategy, we investigated the impact of this spatiotemporal framework on the evolutionary history of a freshwater crustacean morphospecies. The Gammarus balcanicus species complex is widely distributed in the area previously oc…
Phylogenetic Relationship Among Wild and Cultivated Grapevine in Sicily: A Hotspot in the Middle of the Mediterranean Basin
2019
Grapevine (Vitis vinifera ssp. sativa) is a perennial crop especially important for wine and fruit production. The species is highly polymorphic with thousands of different varieties selected by farmers and clonally propagated. However, it is still debated whether grapevine domestication from its wild ancestor (V. vinifera ssp. sylvestris) has been a single event or rather it occurred on multiple occasions during the diffusion of its cultivation across the Mediterranean. Located in the center of the Basin, Sicily is its largest island and has served as a hotspot for all civilizations that have crossed the Mediterranean throughout history. Hundreds of unique grapevine cultivars are still cul…
The long journey of Orthotrichum shevockii (Orthotrichaceae, Bryopsida): From California to Macaronesia
2019
Biogeography, systematics and taxonomy are complementary scientific disciplines. To understand a species' origin, migration routes, distribution and evolutionary history, it is first necessary to establish its taxonomic boundaries. Here, we use an integrative approach that takes advantage of complementary disciplines to resolve an intriguing scientific question. Populations of an unknown moss found in the Canary Islands (Tenerife Island) resembled two different Californian endemic species: Orthotrichum shevockii and O. kellmanii. To determine whether this moss belongs to either of these species and, if so, to explain its presence on this distant oceanic island, we combined the evaluation of…
Clarifying the nomenclature of some Euro-Mediterranean quillworts ( Isoetes , Isoetaceae): Indicator species and species of conservation concern
2018
International audience; To stabilize the application of some names in the genus Isoetes in the Mediterranean biodiversity hotspot, we studied herbarium specimens and imaged spores with scanning electron microscopy, with special reference to those taxa in the I. lon‐gissima and I. histrix groups that were described from France, Algeria and Turkey, and are in need of a taxonomic revision. The following names are lectotypified: I. adspersa, I. boryana, I. delalandei, and I. viollaei. Holotypes of I. perralderiana and I. olympica were ascertained. We conclude that I. boryana (listed in the “Bern Convention” and in the European Union “Habitats” Directive) justifies consideration at species rank,…