Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “EDENTATA”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources
PubMed1991

Chromosome studies on Dasypus, Euphractus and Cabassous genera (Edentata: Dasypodidae).

The somatic and meiotic chromosomes of twenty specimens of the Dasypodidae were studied. The wild specimens belonged to the genera Cabassous, Euphractus and Dasypus. The karyotype of D. novemcinctus showed a diploid chromosome number of 64, although some variation was observed in one specimen where 2n was 65, due to a supernumerary chromosome, and another had a dimorphic pair. D. septemcinctus also had a diploid chromosome number of 64, and showed two variant types due to pericentric inversions and/or centric fusions. E. sexcinctus and C. unicinctus had diploid chromosome numbers of 58 and 50, respectively. These species did not show variant chromosome types, and this was confirmed in meiotic studies. Analysis of the meiotic epithelium of species of Dasypus including the analysis of the synaptonemal complex in pachytene nuclei, showed similar findings to those commonly reported in mammalian meiosis, especially in relation to pairing and formation of the sex bivalent. The evolutionary implications of the chromosome changes in relation to organic evolution are discussed.

Animals↗
PubMed1988

Notes on the typology of the skull of the Myrmecophagidae (Mammalia, Edentata).

The skulls of Myrmecophaga, Tamandua, and Cyclopes are klinorhynch; the upper jaw is situated rostral to the neurocranium and to a varying degree ventral to the plane of the median basis cranii. The median part of the base of the neurocranium is the structure to which the anatomical modifications in the median plane are referred. The kyphosis, which determines the situation of the upper jaw, is prebasically located either within the upper jaw (Myrmecophaga, Tamandua) or at its basis (Cyclopes).

Animals↗
PubMed1986

Morphology of hair of two- and three- toed sloths (Edentata: Bradypodidae).

Micromorphological differences between hairs of the two-toed sloth (Choloepus hoffmanni) and of the three-toed sloth (Bradypus variegatus) were observed by means of scanning electron microscopy. Hairs of the two-toed had longitudinal grooves which exposed a uniform cortex when viewed in cross section. Hairs of the three-toed sloth have irregular transverse fissures and a cortex that contains scattered fusi. These morphological differences support the placement of the two sloth genera into separate families. Hairs of four other xenarthran species are also illustrated.

Animals↗
PubMed1987

The endocranial cast of an early miocene edentate, Hapalops indifferens Ameghino (Mammalia, Edentata, Tardigrada, Megatheriidae). Comparative study with brains of recent sloths.

A natural endocranial cast which represents a complete brain of a specimen of Hapalops indifferens is described. Comparing this cast to brains of actual Tardigrada, it shows a telencephalic morphology and a pattern of neocortical sulci that resemble more the brain of Bradypus rather than that of Choloepus. The neocortical sulci homologate the lateral or corono-lateral, suprasylvian and pseudosylvian sulci. Taking into account the studies of cortical maps in Bradypus and the notable similitude of the pattern of neocortical sulci between Bradypus and H. indifferens, the possible representation of the primary sensitive and motor somatic areas, secondary sensitive somatic area, visual and auditory areas are inferred. As in Bradypus, the primary sensitive and motor somatotopic organizations would be overlapped and would not be mirror images; they would show a predominance of the area of the forelimb. The relative brain size of H. indifferens is similar or higher than that of sloths of the genus Bradypus. The close resemblance between Bradypus and Hapalops, with respect to its brain morphology and relative brain size. is congruent with the current hypothesis of the phylogenetic relations between fossil and recent Tardigrada.

Animals↗
PubMed1983

Quantitative brain organisation in anteaters (Edentata-Tubilidentata).

We can state that the encephalization and the quantitative organisation of the brain in edentates sensu lato exhibit a certain degree of common patterning but also differences between groups that have long been separated. Orycteropus in Africa and the dasypodids in South America can be considered relatively primitive if evolutionary progress is linked essentially with encephalization and neocorticalization. But again, as pointed out by Pirlot (1980), the concept of primitiveness needs careful reconsideration. To this end, more genera from the classical edentate group ought to be worked upon. In particular, the South American bradypodid Choloepus would be of great interest, as well as the African pangolin (Manis). Above all, more data are needed on the behaviour of all those ill-toothed mammals, especially in connection with their olfaction and their balance control as well as with the relative use they make of vision and audition. This project is now at an early stage in Montreal.

Animals↗
PubMed1982

[Hemoglobins XLVI: the primary structure of the alpha-chain of armadillo (Dasypus novemcinctus, Edentata) hemoglobin (author's transl)].

The complete primary structure of the identical alpha-chains of the two hemoglobin components of armadillo (Dasypus novemcinctus) is presented. It was established on the tryptic peptides by automatic Edman degradation. The alignment was done according to the homology with human alpha-chains. 25 differences were found between both chains. A comparison of the functional amino acid residues shows one substitution in the surrounding of the heme, there in the alpha 1 beta 1 - and two in the alpha 1 beta 2 - subunit interface. The two replacements alpha 38(C3)Thr leads to Pro and alpha 44(CD) - Pro leads to Ser may contribute to the high oxygen affinity of the armadillo hemoglobin by destabilization of the T-structure.

Amino Acid Sequence↗
PubMed2001

A molecular phylogeny of two extinct sloths.

Xenarthra (Edentata) is an extremely diverse mammalian order whose modern representatives are the armadillos, anteaters, and sloths. The phylogeny of these groups is poorly resolved. This is particularly true for the sloths (phyllophagans), originally a large and diverse group now reduced to two genera in two different families. Both morphological analyses and molecular analyses of rDNA genes of living and extinct sloths have been used with limited success to elucidate their phylogeny. In an attempt to clarify relationships among the sloths, DNA was extracted and mitochondrial cytochrome b gene sequences were determined from representatives of two extinct groups of sloths (Mylodontidae and Megatheriidae), their two living relatives (two-toed sloths [Megalonychidae], three-toed sloths [Bradypodidae]), anteaters and armadillos. A consistent feature of the latter two species was the nuclear copies of cytochrome b gene sequences. Several methods of phylogenetic reconstruction were applied to the sequences determined, and the results were compared with 12S rDNA sequences obtained in previous studies. The cytochrome b gene exhibited a phylogenetic resolving power similar to that of the 12S rDNA sequences. When both data sets were combined, they tended to support the grouping of two-toed sloths with mylodontids and three-toed sloths with megatheriids. The results strengthen the view that the two families of living sloths adapted independently to an arboreal life-style.

Animals↗
PubMed1996

Mammalian evolution and the interphotoreceptor retinoid binding protein (IRBP) gene: convincing evidence for several superordinal clades.

Phylogenetic relationships of 25 mammalian species representing 17 of the 18 eutherian orders were examined using DNA sequences from a 1.2-kb region of the 5' end of exon 1 of the single-copy nuclear gene known as interphotoreceptor retinoid binding protein (IRBP). A wide variety of methods of analysis of the DNA sequence, and of the translated products, all supported a five-order clade consisting of elephant shrew (Macroscelidea)/aardvark (Tubulidentata)/and the paenungulates (hyracoids, sirenians, and elephants), with bootstrap support in all cases of 100%. The Paenungulata was also strongly supported by these IRBP data. In the majority of analyses this monophyletic five-order grouping was the first branch off the tree after the Edentata. These results are highly congruent with two other recent sources of molecular data. Another superordinal grouping, with similar 100% bootstrap support in all of the same wide-ranging types of analyses, was Artiodactyla/Cetacea. Other superordinal affinities, suggested by the analyses, but with less convincing support, included a Perissodactyla/Artiodactyla/Cetacea clade, an Insectivora/Chiroptera clade, and Glires (an association of rodents and lagomorphs).

Animals↗
PubMed1999

A new nematode, Ansiruptodera scapteromi sp.nov. (Nematoda: Aspidoderidae), recovered from the Argentinean water rat Scapteromys tumidis (Waterhouse, 1837) in Uruguay.

This report describes a new species of aspidoderid nematode, Ansiruptodera scapteromi sp. nov., the second species to be reported in the genus Ansiruptodera Skrjabin and Shikhobalova, 1947. The A. scapteromi sp. nov. is the first species of the genus to be recorded from a rodent host. The new species is clearly different from the only other species, A. ansiruipta (Proença, 1937) Skrjabin and Shikhobalova, 1947, in that it possesses short lateral alae that terminate before the midbody; a smaller cephalic extremity; a shorter esophagus, pharynx, tail, and tail appendage; a smaller sucker; and longer spicules. The two species also differ in the numbers and arrangements of caudal papillae. A. scapteromi appears to be a parasite of capture and the water rats seem to have been infected from Edentata in Uruguay.

Animals↗