Search results for "Cosmopolitan distribution"

2014

The free-living planktonic freshwater bacterium Polynucleobacter necessarius subspecies asymbioticus (> 99% 16S rRNA similarity) represents a taxon with a cosmopolitan distribution and apparently ubiquitous occurrence in lentic freshwater habitats. We tested for intra-taxon biogeographic patterns by combining cultivation-independent and cultivation methods. A culture collection of 204 strains isolated from globally distributed freshwater habitats (Arctic to Antarctica) was investigated for phylogeographic patterns based on sequences of two markers, the 16S–23S internal transcribed spacers and the glutamine synthetase gene (glnA). Genetic distance between isolates showed significant geograph…

A Revision of Sesuvium (Aizoaceae, Sesuvioideae)

2017

Sesuvium and Cypselea are closely related succulent genera within the Sesuvioideae (Aizoaceae). Since Cypselea is nested in Sesuvium in molecular studies and both genera share traits separating them from other members of the subfamily, we propose to include Cypselea in Sesuvium. Sesuvium (incl. Cypselea) comprises 14 species and is distributed worldwide with centres of diversity in southern Africa and North and Central America. Sesuvium comprises erect to procumbent herbs with opposite leaves that often bear conspicuous sheath-like lateral appendages on the petioles (pseudostipules). These and the many-seeded capsules are diagnostic traits, separating Sesuvium from the closely related gener…

Charipinae fauna from New Zealand with descriptions of two new species ofAlloxystaFörster (Hymenoptera: Cynipoidea: Figitidae: Charipinae)

2012

Biologically, New Zealand is an important country for its high levels of endemism. However, the recorded fauna of Charipinae in this country included only three cosmopolitan species: Alloxysta fuscicornis (Hartig), Alloxysta victrix (Westwood) and Phaenoglyphis villosa (Hartig). Here, we describe the first endemic charipines for New Zealand: Alloxysta rubidus n. sp. and Alloxysta thorpei n. sp. This significantly increases the knowledge of cynipoid diversity in Australasia, where this hymenopteran group is very poorly known. The new species are diagnosed, described, illustrated and information about their hosts and distribution is given. Characters useful to distinguish these species are di…

Revision of the genus Anasibirites Mojsisovics (Ammonoidea): An iconic and cosmopolitan taxon of the late Smithian (Early Triassic) extinction

2016

34 pages; International audience; The family Prionitidae Hyatt represents a major component of ammonoid faunas during the Smithian (Early Triassic), and the genus Anasibirites Mojsisovics is the most emblematic taxon of this family. Its stratigraphical range is restricted to the beginning of the late Smithian (Wasatchites distractus Zone). The genus is also characterized by an unusual cosmopolitan distribution, thus contrasting with most earlier Smithian ammonoid distributions that were typically restricted by latitude. Because the late Smithian witnessed an extinction of the nekton (e.g. ammonoids, conodonts) whose amplitude is equal to or larger than that of the end-Permian crisis, the nu…

Stability and endemicity of benthic diatom assemblages from different substrates in a maritime stream on Byers Peninsula, Livingston Island, Antarcti…

2013

16 páginas, 3 tablas, 9 figuras.

Deep-sea Tardigrada from South Shetland Islands (Antarctica) with description of Angursa antarctica sp. nov. (Arthrotardigrada, Halechiniscidae)

1998

A new species of marine tardigrade is described coming from the muddy sediment of the Antarctic deep sea. Angursa antarctica sp. nov. is characterized by the presence of balloon-shaped primary clavae, long lateral cirri, long cephalic cirri, spines on legs I, hemispherical capsule-shaped papillae on legs IV, and short external peduncles. Geographical distribution of the genus Angursa extends to Antarctic waters, suggesting a cosmopolitan distribution for this bathyal and abyssal genus. A table comparing the main differentiating characteristics of the species of Angursa is presented.

Parainoceramyan. gen. forParainoceramusCox, 1954 (exVoronetz, 1936)partim(Bivalvia, Jurassic)

2015

Several Jurassic pterioid bivalve species have been referred to Parainoceramus Cox by different authors, yet this has proved inadequate because the meaning of such genus has been compounded by nomenclatural and idiomatic problems, as well as misinterpretations. Hence, the new genus Parainoceramya is here proposed to accommodate several species previously referred to Parainoceramus, with Crenatula ventricosa J. de C. Sowerby as its type. Permian species originally assigned to Parainoceramus, including the type species, are referred to the genus Kolymia Likharev. All species attributed to Parainoceramus s.l. are reviewed and the new genus is compared with related genera. As here understood, t…