Search results for "Genus"
showing 10 items of 755 documents
Molecular markers and species delimitation: examples from the European batrachofauna
1996
AbstractMolecular techniques have revolutionised zoological systematics since the beginning of the seventies. Within the last twenty years numerous new amphibian species have been described in Europe almost solely on the basis of molecular data. This paper focuses on the use of molecular character state and genetic distance data for the delimitation of species. Case studies of European anurans (Discoglossus, water frogs of the genus Rana) are discussed in the framework of concurring species concepts to illustrate problems of assigning species status to divergent populations on the basis of molecular data.
Systematics of European coastal anchovies (genus Engraulis Cuvier).
2021
Reports of morphological differences between European anchovy (Engraulis cf. encrasicolus) from coastal and marine habitats have long existed in the ichthyologic literature, and have given rise to a long-standing debate on their taxonomic status. More recently, molecular studies have confirmed the existence of genetic differentiation between the two anchovy ecotypes. Using ancestry-informative markers, we show that coastal anchovies throughout the Mediterranean share a common ancestry, and that substantial genetic differentiation persists in different pairs of coastal/marine populations despite the presence of limited gene flow. On the basis of genetic and ecological arguments, we propose t…
Allozymic variation and divergence in three species of Antirrhinum L. (Scrophulariaceae-Antirrhineae)
1999
Abstract An allozymic study of three wild species of Antirrhinum L.—A. lopesianum RothmA. mollissimum Rothm. and A. microphyllum Rothm.—is described. All are members of subsectionKickxiella Rothmand are narrow-range endemics of the Iberian Peninsula. The variability of the different loci, as well as the number and mobility of the alleles, differ among the three species, a demonstration of the usefulness of allozymes for the systematics of the genus. The finding of alleles unique to each species indicates high divergence among species suggesting ancient diversification, and supports the hypothesis of a geographical model of speciation. All three species show high levels of within-species var…
Beiträge zur Kenntnis der Gattung Pseudoscabiosa (Dipsacaceae)
1997
Die Gattung Pseudoscabiosa DEVESA wird untersucht unter besonderer Berucksichtigung der Bedeutung der Mikromorphologie der Behaarung fur die Systematik dieser Gattung. Eine neue nordafrikanische Art, Pseudoscabiosa africana (FONT QUER) ROMO, CIRUJANO, PERIS & STUBING comb. & stat. nov., wird aufgestellt. The genus Pseudoscabiosa DEVESA is reviewed, stressing the importance of the micromorphology of the hair-covering for the systematics of this genus. A new Northafrican species is proposed, Pseudoscabiosa africana (FONT QUER) ROMO, CIRUJANO, PERIS & STUBING comb. & stat. nov.
The enigmatic case of the genus Argyresthia in the Azores Islands (Lepidoptera Argyresthiidae)
2020
The species composition of the genus Argyresthia Hübner, 1825 in the Azores is examined. Argyresthia brumella, sp. nov., is described and illustrated from Terceira and Flores Islands. Argyresthia minusculella Rebel, 1940, syn. nov. and Tinea poecilella Rebel, 1940, syn. nov. are synonymized with Argyresthia atlanticella Rebel, 1940. The high variability of A. atlanticella is revealed through the polymorphic wing pattern and the intraspecific genetic divergence of the DNA barcode COI in the specimens examined.
The first record ofDinesus(Trilobita, Dinesidae) in the Cambrian of the Mediterranean region
2011
An important problem facing inter-regional correlation in the Cambrian is the scarcity of shared taxa between different palaeogeographic domains. Currently, species of the Corynexochida are proposed as tools to define the base of Cambrian Series 3. However, few Mediterranean Corynexochida species are known. A specimen of Dinesus truyolsi comb. nov. from the middle Cambrian of Spain represents the first record of this genus in the Acadobaltic province. Erbia and Tingyuania are accepted as junior subjective synonyms of Dinesus, and we now recognize 22 species within this genus. Dinesus has been found previously in lower to middle Cambrian strata of Australia, Russia, Kazakhstan, North America…
Palaeophylloxera nov. gen., The firstfossil specimen of the family Phylloxeridae (Hemiptera, Phylloxeroidea); Lower Miocene of Spain
1999
A fossil alate aphid from the Lower Aragonian (Lower Miocene) deposits of Rubielos de Mora (Teruelprovince) in eastern Spain is described as Palaeophylloxera seilacheri nov. gen. and sp. It is the first fossil specimen described within the Family Phylloxeridae. The principal differences between this genus and other representatives of the Phylloxeridae (and also the extinct Elektraphididae) are the apparent presence of an oblique vein on the hind wing, the presence of distinctly visible transverse striae on antennal segment III, and the peculier venation on the fore wings.
Generic concept of the phytoseiids (Acari: Phytoseiidae) according to Athias-Henriot
2010
The economic importance of the Phytoseiidae motivated many scientists to work on the systematics of this family. One of them was the French acarologist Claire Athias-Henriot. In her first work, she tackled the question of supraspecific groupings within this family from an evolutionistic point of view, and suggested a system for numbering dorsal shield setae, that could be applied to both hypotrichous and holotrichous forms. She also looked for other characters, such as the ratios of the distance between the insertions of some setae on dorsal and sternal shields, the presence of macrosetae on legs, and the length/width ratio of the ventrianal shield. Following Dosse (1957; 1958) who used the…
Paramblypterus duvernoyi(Actinopterygii): skull morphology and intra-specific variation, and its implications for the systematics of paramblypterid f…
1999
ABSTRACT More than 300 specimens of Paramblypterus duvernoyi from four lakes of the Lower Permian of Germany are examined to determine intra-specific variation of this species and to revise the diagnosis of the genus Paramblypterus. For the first time, a three-dimensional model of the skull and the snout of Paramblypterus is reconstructed. A partial tooth bearing premaxilla, which forms the anterior most part of the gape, is described; in contrast, the absence of a premaxilla had until now been considered a synapomorphy of the genus Paramblypterus. Information obtained from the study of P. duvernoyi has required a new revision of Paramblypterus gelberti. A comparison between the two species…
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…