Search results for "Axon"
showing 10 items of 2126 documents
An overview of the phylogeny of the families Lafoeidae and Hebellidae (Hydrozoa:Leptothecata): their composition and classification
2006
A cladistic analysis of the genera of the family ‘Lafoeidae’ was performed in order to investigate suprageneric classifications and the boundaries of the family, as well as to organise the available morphological data and discuss the possible evolution of some morphological characters. Our results suggest that the former ‘Lafoeidae’ must be separated into two families: the Hebellidae and the Lafoeidae (including the subfamilies Lafoeinae and Zygophylacinae).
Micromorphological approach to the systematics of Mediterranean Isoëtes species (Isoëtaceae, Lycopodiophyta): analysis of the megaspore surface
2012
Megaspore ornamentation is one of the few morphological characters used in the taxonomy of the genus Isoëtes. In the present work, we test the application of this character for distinguishing some Isoëtes species occurring in the Mediterranean: Isoëtes sicula, which according to some authors should be included as a variety in I. histrix, and the recently described I. todaroana, whose affinity with other taxa is currently unknown. Two additional species (I. duriei, I. velata) were also included in the analysis. The megaspores were studied using scanning electron microscopy combined with energy-dispersive X-ray spectroscopy and chemical treatment. In all species, the megaspore surface is cove…
An inventory of the names of vascular plants endemic to C Mediterranean and described from Tunisia
2019
The census of the loci classici of the 98 vascular plants described from Tunisia, endemic to Tunisia or to Tunisia and the surrounding countries, is here presented and described. The effective place of publication of accepted names, basionyms, and homotypic synonyms were identified and critically verified. The geographic information on the loci classici was excerpted from the protologues, as well as information on typification for the taxa described before 1 January 1958. The names without holotype are 48. For 7 of them a lectotypification is already available in literature, 5 are lecotypified here, while 32 currently accepted taxa still need type designation. The new names Festuca scholzia…
Reëvaluation of Orthotrichum Rhytiore (Orthotrichaceae)
2008
Examination of the holotype of Orthotrichum rhytiore B. H. Allen reveals gametophytic characters which support the placement of the species in Ulota. The species is peculiar within the genus due to its unusual sporophyte morphology, and the occurrence of these sporophytic characters in Ulota is discussed. Ulota rhytiore (B. H. Allen) F. Lara, Garilleti, Albertos & Mazimpaka comb. nov. is the first known species of the genus in tropical America.
Systematics and population genetics of the coldwater (Etheostoma ditrema) and watercress (Etheostoma nuchale) darters, with comments on the Gulf dart…
2005
Abstract Current taxonomy of the Etheostoma asprigene species group recognizes four species, two of which ( Etheostoma ditrema Ramsey and Suttkus and Etheostoma nuchale Howell and Caldwell) are restricted to isolated springs and spring-fed stream systems above the Fall Line of the Mobile Basin of Alabama, Georgia, and Tennessee. Previous studies of morphological and biochemical variation between disjunct populations of E. ditrema support the presence of multiple independent lineages. Unfortunately, the lack of phylogenetic methodology has made it impossible to distinguish historically differentiated non-sister taxa from currently intergrading sister lineages. The current study examines memb…
A new species of glirid rodent Vasseuromys from the Aragonian (Miocene) of the Ebro Basin (North−Eastern Spain)
2012
We describe a new species of Vasseuromys from the locality of Pico del Fraile 2 (PF2) in the Ebro Basin of northeastern Spain, which has yielded a fauna comprising several rodents and insectivores (Eumyarion cf. weinfurteri, Mega−cricetodon cf. primitivus, Democricetodon aff. hispanicus, Spermophilinus cf. besana, Microdyromys cf. legidensis, Galerix sp., and Lagomorpha indet.) indicative of Aragonian zones C or D. Vasseuromys cristinae sp. nov. differs from other Vasseuromys species in the constant presence of four extra ridges on the lower molars, one of them being connected to the posterolophid in the posterior valley, as well as three extra ridges on the upper molars, with none of them …
Towards a complete phylogeny of African Melastomateae : systematics of Dissotis and allies (Melastomataceae)
2020
Aegopinella bourdieri nov. sp. (Gastropoda: Zonitidae),une espèce nouvelle du Pléistocène normand (France)
1989
St Pierre-les-Elbeuf (Normandy, NE France) is a reference site for the middle and the upper Pleistocene of NW France. In the eastern part of the quarry, the paleosoils Elbeuf III and IV are truncated, white sands and a small tufa lay on Elbeuf IV. Similar deposits have been recognized at Vernon (Seine valley) and at Arrest (northern France). They are probably contemporaneous (Holsteinian) and each of them has yielded an interglacial malacological fauna. The faunal communities are interesting because they are composed by species living up to now in this country, by emigrated species and by fossil species. Among them, A. bourdieri is a new fossil taxa, endemic of Holsteinian tufas of Normandy…
A reassessment of the sections of the genus Cytisus Desf. (Cytiseae, Leguminosae)
2006
Recent morphological and molecular research on Cytisus and allied genera has produced a great deal of new data relevant to systematics, which have not yet been incorporated into a consistent classification system of the genus. We have compared and evaluated recently published cladograms and phenograms based on morphological and molecular (nuclear and plastid DNA) characters. The genus Cytisus sensu lato, including Calicotome, Chamaecytisus, Chronanthus, and Lembotropis, appears to be monophyletic. A subdivision of the genus Cytisus in 13 sections is presented; one species, C. tribracteolatus, remains incertae sedis. A new section (C. sect. Dendrocytisus) and two new combinations for taxa in…
A taxonomical study of the subtribe leontodontinae based on the distribution of phenolic compounds
1993
Abstract Evaluation of the phenolic constituents of five species belonging to the subtribe Leontodontinae (family Asteraceae) allowed the identification of ten flavonoid and eight phenolic acids by means of HPLC and other standard methods. The role of these compounds in relation to the morphological characteristics in the systematics of the subtribe is discussed.