Search results for "Systematics"
showing 10 items of 6702 documents
Unique growth pattern of Metoposaurus diagnosticus krasiejowensis (Amphibia, Temnospondyli) from the Upper Triassic of Krasiejów, Poland
2013
Morphology and bone histology of femora, tibiae, and fibulae of the temnospondyl Metoposaurus diagnosticus krasiejowensis from the Upper Triassic locality of Krasiejow (Poland) are studied for the first time. The growth pattern of Metoposaurus as preserved in a small growth series of femora, shows a regular alternating sequence of fast and slow growth phases, which are interpreted as representing zones and annuli. The slow growth phases (annuli) of the inner and outer cortex as well as those of different specimens are of a regular broad thickness. Such broad annuli are so far unknown for any vertebrate and make the growth pattern for Metoposaurus unique. These slow growth phases always cont…
Raunoloma longiceps(Linnavuori, 1977) (Hemiptera: Heteroptera: Cydnidae): First Record from Uganda
2015
The present note reports the first Ugandan record of Raunoloma longiceps (Linnavuori, 1977), a rarely collected African burrower bug species (Hemiptera: Heteroptera: Cydnidae). This record increases the number of Cydnidae genera reported from Uganda to seven, with a total of 12 species. Cydnidae belong to the superfamily Pentatomoidea and are known by almost 700 species distributed in all zoogeographical regions of the world (Lis 1996, 1999, 2006; Lis & Lis 2014). Species of the family are well-known by the common name of burrower (or burrowing) bugs, because of their ability to dig into the ground. This behaviour is possible mainly due to their strong and well-developed tibial and coxal co…
Pretarsal structures in the family Cydnidae sensu lato (Hemiptera: Heteroptera: Pentatomoidea)
2010
New data on the pretarsus in Cydnidae sensu lato are presented; 56 species of 38 genera are studied based on the SEM techniques. Pretarsal structures in Cydnidae s.l. are demonstrated to be not uniform; some are typically pentatomoid, and some are atypical for Pentatomoidea. Structures associated with the unguitractor plate, described for the first time by Weirauch (2005) in Reduviidae, and not reported for Cydnidae s.l. in the past, are described for the first time.
Effects of intensity and duration of infection by a hemiparasitic plant, Rhinanthus serotinus, on growth and reproduction of a perennial grass, Agros…
1999
Arising from annual variation in parasitic plant population densities, substantial yearly changes may occur in the parasitic load of an individual perennial host. We conducted two two-year greenhouse pot experiments to examine the effects of varying intensities and duration of infection by an annual root hemiparasitic plant, Rhinanthus serotinus, on the growth and reproduction of its perennial host grass, Agrostis capillaris. In the first experiment, one host plant was growing either alone or under a load of 1 or 3 root hemiparasitic plants for one growing season, and during the next season all hosts continued their life free of hemiparasites. In the second experiment, the host plants eithe…
The microstructural variability of the intercentra among temnospondyl amphibians
2014
The histology of the vertebral centrum of the morphologically diverse Temnospondyli is poorly known. In this study, the variability of the histological framework of various taxa from several Permian and Triassic localities was investigated for the first time. Twelve intercentra, forming the anterior part of the diplospondylous centra of temnospondyls, were examined histologically. The intercentra of all studied taxa share a highly vascularized cortex on the ventro-lateral side and primary and secondary trabecular, endochondral bone on the dorsal side. A high variability is present, among others, within the arrangement of the vascular cavities, the density of the trabeculae and the distribut…
Toward a Phylogenetic Classification of the Lauraceae: Evidence from matK Sequences
2000
Abstract The larger part of the matK gene and the (3′−) adjacent spacer have been sequenced and used for phylogenetic analyses in 48 species of Lauraceae from all parts of their geographical range, and in three outgroup taxa. Except for the aberrant genera Hypodaphnis and Cassytha, the genetic divergence within the family is surprisingly low. In spite of this, several clades receive sufficient support to change our current concepts of relationships within the family. Particularly well supported is a Beilschmiedia–Cryptocarya clade that had been recognized by wood anatomy, but not in most of the recent morphological systems. The separation between taxa with involucrate and non-involucrate in…
Thalassobius mediterraneus gen. nov., sp. nov., and reclassification of Ruegeria gelatinovorans as Thalassobius gelatinovorus comb. nov.
2005
A Gram-negative, slightly halophilic, non-pigmented, strictly aerobic, chemo-organotrophic bacterium was isolated from sea water off the western Mediterranean coast near Valencia (Spain). This strain was able to grow on several organic acids and amino acids added to a minimal medium as carbon sources, but used few carbohydrates or yielded slight growth when sugars were used. Phylogenetic analysis based on an almost complete 16S rRNA gene sequence revealed that strain XSM19T was a member of the Roseobacter group within the ‘Alphaproteobacteria’, with its closest phylogenetic neighbour being Ruegeria gelatinovorans (97·6 % sequence similarity). Following a polyphasic approach, it was conclude…
The Phylogenetic Analysis of Variable-Length Sequence Data: Elongation Factor–1α Introns in European Populations of the Parasitoid Wasp Genus Pauesia…
2001
Elongation factor-1alpha (EF-1alpha) is a highly conserved nuclear coding gene that can be used to investigate recent divergences due to the presence of rapidly evolving introns. However, a universal feature of intron sequences is that even closely related species exhibit insertion and deletion events, which cause variation in the lengths of the sequences. Indels are frequently rich in evolutionary information, but most investigators ignore sites that fall within these variable regions, largely because the analytical tools and theory are not well developed. We examined this problem in the taxonomically problematic parasitoid wasp genus Pauesia (Hymenoptera: Braconidae: Aphidiinae) using con…
Phylogeny of prickly poppies,Argemone (Papaveraceae), and the evolution of morphological and alkaloid characters based on ITS nrDNA sequence variation
1999
Evolutionary relationships withinArgemone (Papaveraceae) were inferred from nucleotide variation in nuclear ribosomal DNA. A complete representation of the genus was achieved by using herbarium material to a large extent (74%). Four distinct clades can be recognized based on the molecular results. The support for the different clades varies greatly due to a very uneven distribution of characters. Although some clades are largely unresolved, some unexpected relationships, for example the sister group relationship of the relict speciesA. subintegrifolia to the rest ofArgemone, were found. The evolution of morphological and alkaloid characters against the background of the obtained phylogeny i…
<strong>The mesothoracic wings of Afrotropical Scutelleridae (Hemiptera: Heteroptera): morphology and taxonomic significance</strong>
2013
Mesothoracic wings have been examined and compared in 32 species representing 20 genera of Afrotropical Scutelleridae. Morphological characters of the corium are described. Three main types of mesothoracic wing venation patterns can be recognized. The taxonomic significance of forewing characters in Scutelleridae is briefly discussed.