Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Lagomorpha”

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 55 records · Page 3Linked to original sources

Redescription of Andrya cuniculi (Blanchard, 1891) (Cestoda: Anoplocephalidae), a parasite of Oryctolagus cuniculus (Lagomorpha) in Spain.

Andrya cuniculi (Blanchard, 1891) (Cestoda: Anoplocephalidae) is redescribed from Oryctolagus cuniculus (L.) from Spain. Large ranges of variability in body length and width, testes number and position of the cirrus sac were observed. An external seminal vesicle covered with small glandular cells is present. The pattern of development of the uterus is similar to that of Andrya rhopalocephala (Riehm, 1881). The only reliable differential characters to distinguish A. cunliculi from A. rhopalocephala are the position of the uterus in gravid segments and the position of the testes in mature segments. The uterus of A. cuniculi occupies the median field and parts of the lateral fields but is restricted to the median field in A. rhopalocephala. Testes are distributed more symmetrically lateral to the female organs in A. cuniculi but are mostly antiporal in A. rhopalocephala.

Animals↗

Spermiogenesis and spermatozoon ultrastructure of the cestode Mosgovoyia ctenoides (Cyclophyllidea: Anoplocephalidae), an intestinal parasite of Oryctolagus cuniculus (Lagomorpha: Leporidae).

Ultrastructural characters in spermiogenesis and spermatozoa are considered important tools to elucidate the phylogenetic relationships within the Platyhelminthes. In the Anoplocephalidae, ultrastructural data refer to the spermatozoon of 14 species, whereas data on spermiogenesis refer to only 7 species. The present study focused on the spermiogenesis and spermatozoon of the anoplocephalid cestode Mosgovoyia ctenoides, as revealed by transmission electron microscopy. Type IV spermiogenesis was detected, beginning with the formation of a differentiation zone containing 2 centrioles, with a centriolar adjunct and vestigial striated rootlets. Different forms of the latter character have been described in other anoplocephalids. This study supports spermiogenesis of type IV as the most frequent in the Anoplocephalidae and confirms the presence of a centriolar adjunct in yet another type IV spermiogenesis species. The spermatozoon of M. ctenoides possesses 1 axoneme of the 9+ '1' trepaxonematan type, 2 crestlike bodies, dense plates, and granules of electron-dense cytoplasmic material, nucleus, and twisted cortical microtubules. It was again confirmed that the presence of granular material and the absence of both a periaxonemal sheath and intracytoplasmic walls are constant characters in the spermatozoa of all the Anoplocephalinae.

Animals↗

A cladistic analysis of the Trichostrongyloidea (Nematoda).

A morphologically based cladistic analysis of 40 genera included within the Trichostrongyloidea (Amidostomatidae, Dromaeostrongylidae and Trichostrongylidae) is proposed. Two genera were used as outgroups, one from the Strongylina and the other from the Ancylostomatina. Seven genera do not appear in the matrix because some significant morphological characters remain unknown for these genera. Nonetheless, except for Moguranema which is excluded as incertae sedis, a likely systematic position could be assigned to them based on the morphological characters that are known. The classification which best fits the consensus tree is composed of three families. In adding the genera not included in the tree, we obtain: (i) Trichostrongylidae with three sub-families, Amidostomatinae (four genera), Filarinematinae (three genera) and Trichostrongylinae (five genera); (ii) Haemonchidae with two sub-families: Ostertagiinae (eight genera) and Haemonchinae (five genera); (iii) Cooperiidae with three sub-families: Libyostrongylinae (five genera), Obeliscoidinae n. subfam. (five genera) and Cooperiinae (ten genera). Dromaeostrongylus and Ortleppstrongylus, whose females have a caudal spine, are excluded from the Trichostrongyloidea and are placed in the Molineoidea. The hypotheses relating to the evolutionary history of the Trichostrongyloidea are: the origin of the superfamily could have occurred during the upper Cretaceous period. The two most ancient sub-families (Amidostomatinae and Filarinematinae) would be of Gwondwanan origin and evolved during the Paleocene period within Neotropical aquatic birds and within the Australian marsupials. The Trichostrongylinae would have arisen during the Eocene period within birds and then adapted to diverse archaic mammals in the Neotropical region on one hand and in the Nearctic region, on the other hand and lastly adapted to the Lagomorpha and subsequently to the Ruminantia. In both families originating from the Trichostrongylidae, the adaptation to the Lagomorpha may have taken place during the Oligocene but in a different way. In the Haemonchidae, the Ostertagiinae may have passed directly from the Neartic region to Europe. In the Cooperiidae, the adaptation to Lagomorpha may have occurred either within the Libyostrongylinae which may have remained in the Ethiopian region since the Paleocene, or, more likely, by the passage of the Obeliscoidinae from the Nearctic region to the Asian, through the Bering strait. In all cases, the adaptation of the Trichostrongyloidea of Lagomorpha to Ruminants apparently took place during the Miocene, mainly in the Palearctic and the Ethiopian regions.

Adaptation, Physiological↗

Ochotona princeps (pika) myoglobin: an appraisal of lagomorph phylogeny.

Myoglobin was purified from skeletal muscle of the pika (Ochotona princeps) and its primary structure was determined. This sequence was added to the set of 64 already known vertebrate myoglobin sequences and used to evaluate the phylogenetic position of the pika among other mammals, using a computerized search procedure based on maximum parsimony criteria. The pika is clearly related to the rabbit (Oryctolagus cuniculus), with which it is traditionally associated as a member of the order Lagomorpha. A monophyletic group composed of Lagomorpha, Scandentia, and Carnivora is a consistent feature of the dendrograms produced. An association of Carnivora and Lagomorpha casts doubt on the results of those investigations using rabbit antisera in systematic studies and depending on carnivores as an outside reference group for cladogram construction.

Amino Acid Sequence↗

Mammalian phylogeny inferred from multiple protein data.

On the basis of multiple protein data, the phylogenetic relationships among the major clades of eutherian mammals, Primates, Cetacea, Artiodactyla, Carnivora, Lagomorpha, Myomorpha, and Caviomorpha, were analyzed by the maximum likelihood (ML) method, together with the maximum parsimony (MP) method and the neighbor joining (NJ) method. Using nineteen protein data, we first reexamined the hypothesis of rodent polyphyly proposed by Graur et al. (1991) based on the four taxon system, consisting of human, mouse (or rat), guinea-pig and an outgroup. The ML analysis does not support the rodent polyphyly, but strongly favors the traditional view of rodent monophyly representing the Myomorpha-Caviomorpha association. In the second analysis, the phylogenetic position of Lagomorpha were reexamined using three sets of multiple protein data, 13 mitochondrial DNA-coded proteins from rodents, rabbit, human, seals, bovine, whales and opossum, 25 protein data from human, rabbit and rodents and an outgroup, and 20 protein data from human, rabbit, bovine (or pig) and rodents. Our analysis favors the closer affinity of Lagomorpha to Primates than to Rodentia. The branching sequence of seven mammalian groups revealed by the present analyses is as follows: Myomorpha-Caviomorpha clade (Rodentia), rabbit, Primates, Carnivora, and Artiodactyla-Cetacea clade. Judging from the branch lengths measured by the numbers of synonymous substitutions, a series of divergence of these mammals is likely to be bush-like. The rapid rate of rodent evolution was reexamined in the light of the new phylogeny.

Amino Acid Sequence↗

[Redescription of Helminthoxys tiflophila and consideration of the systematics of Oxyuridae parasites of rodents].

--Morphology--Helminthoxys tiflophila (Vigueras, 1943) parasite in Capromys prehensilis (Caviomorpha, Rodent) is redescribed. In the males of this species occurs a peculiar type of ventral cuticular swellings. The adherence with cuticula of females is not obtained by hooking, but by gluing: a ventral hypodermal secretion coagulates on surface of swellings. --Systematic--The genus Helminthoxys Freitas, Lent and Almeida, 1937 is compared by means of cladistic method with the most closely related forms: 1--The genera Helminthoxys and Octodonthoxys Quentin, Courtin and Fontecilla, 1975 cannot be distinguished using this method, 2--Helminthoxys-Octodonthoxys is the sister group of Wellcomia, Sambon 1907, Protozoophaga Travassos, 1923. 3--These four genera, all parasite in Hystricognathi Rodents may be opposed as a sister-group to the Oxyuridae parasite in Sciurognathi Rodents and Lagomorpha. 4--The whole Oxyuridae parasite in Rodents (excepted Citellina Prendel, 1948) and Lagomorpha form a monophyletic group.

Animals↗

Lung morphology in rodents (Mammalia, Rodentia) and its implications for systematics.

A new nomenclature of the lung lobes and of the bronchial tree is presented, with which the lungs in 40 species of 11 rodent families are described. Whole, fixed lungs and silicone casts of the bronchial tree are tested for 23 characters, based on the distribution of lung lobes, the number and geometry of first order bronchi, the pulmonary blood supply, and lung symmetry. Ten lung morphotypes are recognized, seven of them representing one or more families: Castor type (Castoridae), Cryptomys type (Bathyergidae), Ctenodactylus type (Ctenodactylidae), Eliomys type (Gliridae), Myocastor type (Myocastoridae), Octodon type (Octodontidae and Echimyidae) and Rattus type (Sciuridae, Muridae pt. and Dipodidae). The Hydromys type is found only in Hydromys chrysogaster (Muridae), while Galea type A and B both appear in Galea musteloides (Caviidae). The data are phylogenetically analyzed by the program PAUP 4.0 using as outgroup Lagomorpha or Insectivora. On the species level, there are no well-resolved cladograms. On the family level, the cladograms do not contradict traditional rodent systematics with one exception: the Caviidae do not fall within Caviomorpha or even within the Hystricomorpha, but form a sister group to Dipodidae (Myomorpha). This appears to be a result of convergence. The lungs of Gliridae are more similar to those of Muridae than to those of Sciuridae. Included in the ingroup, Oryctolagus (Lagomorpha) forms a clade with Caviidae + Dipodidae. Thus, the "Glires hypothesis" is neither supported nor refuted.

Animals↗

Basal metabolic rates in mammals: taxonomic differences in the allometry of BMR and body mass.

No single equation adequately describes the allometric relation between body mass and BMR for mammals. Least squares regression of log-transformed data for 248 eutherian species results in a line with a slope (-0.30) significantly different from that of Kleiber's line (-0.25). Interordinal comparisons of least squares regressions of log-transformed BMR and mass suggest that the Insectivora have a significantly steeper slope to their allometric relationship than do most other orders, while the non-insectivore orders are statistically homogeneous with respect to slope. With respect to elevation, Edentata have the lowest BMRs; Marsupialia, Primates and Chiroptera are indistinguishable from each other but above the edentates; Primates, Chiroptera, Rodentia, Lagomorpha and Carnivora form the next highest homogeneous grouping; and Artiodactyla have the highest BMRs, significantly greater than all but Lagomorpha and Carnivora. Analysis of intraordinal variation within the Rodentia suggests significant heterogeneity among families in BMR-mass allometry.

Animals↗