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A propos de quelques noms de na ades : Pourquoi faut- il oublier Potomida et Pseudunio ?
Cristian R. Altaba
MalaCo , 2007,
Abstract: The study of European naiads has long been hampered by troubling problems in nomenclature, rising from a tradition plagued with unjustified usages, and yielding the highest recorded synonymy rates. Here two genus-level names are shown to be still incorrectly used. Pseudunio Haas, 1910 was originally introduced on purely conchological grounds to seggregate Unio auricularius Spengler, 1798 (=U. sinuatus Lamarck, 1819) from Margaritifera Schumacher, 1816. Pseudunio has recently been resurrected by several authors to subgenus and even genus level in monothetic schemes based on variable hinge traits, but molecular genetics and anatomy both fail to support such multiplication of genera, and point instead at the cohesiveness of Margaritifera as the single extant genus of margaritiferids. Potomida Swainson, 1840 was introduced to group all European naiads possessing a heavy hinge, a grouping that is now known to be far from natrual. The type of Potomida is by original designation Unio sinuatus; thus it constitutes a synonym of Margaritifera, as first recognized by Gray (1847). However, Potomida has frequently (but not universally) been used to allocate Unio littoralis Cuvier, 1774, on the basis that the description of this genus includes a figure that can be identified as this species. Actually, the correct genus name for it is Psilunio Stefanescu, 1896; this has priority over Rhombunio Germain, 1911. Therefore, both Pseudunio and Potomida must be abandoned for good; the correct names for the two naiads involved are Margaritifera auricularia (Spengler, 1798) and Psilunio littoralis (Cuvier, 1774).
Primer registro fósil de Procyon cancrivorus (G. Cuvier, 1798) (Carnivora, Procyonidae) en la Argentina
Soibelzon, Leopoldo Héctor;Zurita, Alfredo Eduardo;Morgan, Cecilia Clara;Rodríguez, Sergio;Gasparini, Germán Mariano;Soibelzon, Esteban;Schubert, Blaine W.;Mi?o-Boilin, ángel Ramón;
Revista mexicana de ciencias geológicas , 2010,
Abstract: we present the first fossil record of procyon cancrivorus (cuvier, 1798) for argentina. specimen pve-f 44 (first lower molar) was exhumed from levels assignable to the late pleistocene (lujanian) in the coastal cliffs of the bermejo river in the vicinity of villa escolar, formosa (26°36's, 58°40'w). this is also the first south american record of procyon with accurate stratigraphic provenance, since previous records from brazil lack stratigraphic context. procyonids are represented in south america by jive living genera (bassaricyon allen, nasuella hollister, potos geoffroy saint-hilaire and cuvier, procyon storr and nasua storr). of these, only procyon and nasua have paleontological records (late pleistocene-holocene) in brazil, uruguay and bolivia. the results of geometric and traditional morphometric analyses comparing specimen pve-f 44 with the two known procyon species (p. cancrivorus and p. lotor) indicates the specimen belongs to the south american species p. cancrivorus. in addition, the associated palaeofauna is composed by intertropical (e.g., holmesina paulacoutoi) and pampean-patagonian elements (e.g., megatherium, toxodon, glyptodon, pampatherium typum).
Anatomical description of the leg muscles of Procyon cancrivorus (Cuvier 1798)
Firmino Cardoso Pereira,Vanessa Morais Lima,Kleber Fernando Pereira
Biotemas , 2010,
Abstract: The Procyon cancrivorus, as well as its entire family, is an endemic species of the Americas. It is widely found throughout the Brazilian territory and it inhabits all biomes, particularly the cerrado. This study used five adult specimens of P. cancrivorus for the characterization of the leg muscles. The animals were collected on roads (i. e. they had been killed by accident). The muscles were dissected, observing their proximal and distal insertions macroscopically, together with their topographic relationships to the arteries and nerves. The muscles studied are considered muscles of the tibia. The cranial tibial muscles, brevis, longus, long digital extensor and lateral extensor digitorum are craniolaterally distinct in the tibia, and the gastrocnemius muscles, lateral flexor of the fingers, popliteus, flexor digitorum, flexor digitorum and medial tibial flow are located in the caudal region of the tibia. The muscles of this group act as flexors and extensors of the hock joint and as flexors and extensors of the digital joints, except the popliteal muscle that acts as a flexor of the knee joint. The muscles studied were compared with their muscles in domestic carnivores, like the dog and cat, and great similarity was found.
Verspreiding en habitats van Unio caffer Krauss, 1848 (Bivalvia: Unionoida: Unionidae) in Suid-Afrika gebaseer op die rekords in die databasis van die Nasionale Varswaterslakversameling  [cached]
K. N. de Kock,C. T. Wolmarans
Suid-Afrikaanse Tydskrif vir Natuurwetenskap en Tegnologie , 2010, DOI: 10.4102/satnt.v29i4.21
Abstract: Die kosmopolities-verspreide Unionoida bereik hul grootste diversiteit in Noord-Amerika. In Suid-Afrika word twee genera van die familie Unionidae, naamlik Unio en Coelatura wat vier spesies insluit, aangetref. Hierdie artikel handel oor die verspreiding en habitats van Unio caffer Krauss, 1848 gebaseer op die rekords in die Nasionale Varswaterslakversameling (NVWSV) van Suid-Afrika. Alhoewel dit elders in Suid-Afrika sporadies aangetref is, is die Wes-Kaap die enigste provinsie waarvan geen monster op rekord in die databasis van die NVWSV is nie. Van die 58 monsters wat op rekord is, is die meerderheid in riviere (32.8%) en damme (20.7%) versamel en in watertoestande wat as standhoudend, staande, helder en vars beskryf is. ’n Temperatuur-indeks wat vir hierdie spesie bereken is, het dit vyfde in rangorde geplaas van die 12 Bivalvia-spesies wat in die databasis verteenwoordig word op grond van ’n assosiasie met lae omgewingstemperature. ’n Besluitnemingsboom-analise het aangedui dat temperatuur, substratum en waterbronne die mees betekenisvolle bydrae gelewer het tot die daarstelling van die gedokumenteerde geogra ese verspreiding van U. caffer. Omdat omvattende opnames van varswater Mollusca deur staatsinstansies reeds in die tagtigerjare van die vorige eeu uitgefaseer is en die meerderheid versamelpunte sedertdien nie weer gemonster is nie, is kennis oor hul huidige stand van bewaring en spesiediversiteit gebrekkig. Negatiewe resultate by drie voormalige lokaliteite van U. caffer wat wel intussen deur die outeurs besoek is, dui egter daarop dat die voortbestaan daarvan, soos van sommige verwante spesies elders in die wêreld, bedreig word. Dit word bepleit dat opnames van varswater Mollusca met die gedokumenteerde verspreiding in die databasis van die NVWSV as riglyn, beplan en uitgevoer behoort te word. Die resultate van sulke opnames behoort ’n groot bydrae te lewer om die huidige stand van die verspreiding en spesiediversiteit van die varswater Mollusca van Suid-Afrika sinvol te evalueer. Distribution and habitats of Unio caffer Krauss, 1848 (Bivalvia: Unionoida: Unionidae) in South Africa based on the records in the database of the National Freshwater Snail Collection The distribution of the Unionoida is almost cosmopolitan and reaches its greatest diversity in North America with 860 currently recognized valid species. Two genera of the family Unionidae, Unio and Coelatura, comprising four species, occur in South Africa. This article focuses on the distribution and habitats of Unio caffer Krauss, 1848 based on the records in the database of the
The Complete Maternally and Paternally Inherited Mitochondrial Genomes of the Endangered Freshwater Mussel Solenaia carinatus (Bivalvia: Unionidae) and Implications for Unionidae Taxonomy  [PDF]
Xiao-Chen Huang, Jun Rong, Yong Liu, Ming-Hua Zhang, Yuan Wan, Shan Ouyang, Chun-Hua Zhou, Xiao-Ping Wu
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0084352
Abstract: Doubly uniparental inheritance (DUI) is an exception to the typical maternal inheritance of mitochondrial (mt) DNA in Metazoa, and found only in some bivalves. In species with DUI, there are two highly divergent gender-associated mt genomes: maternal (F) and paternal (M), which transmit independently and show different tissue localization. Solenaia carinatus is an endangered freshwater mussel species exclusive to Poyang Lake basin, China. Anthropogenic events in the watershed greatly threaten the survival of this species. Nevertheless, the taxonomy of S. carinatus based on shell morphology is confusing, and the subfamilial placement of the genus Solenaia remains unclear. In order to clarify the taxonomic status and discuss the phylogenetic implications of family Unionidae, the entire F and M mt genomes of S. carinatus were sequenced and compared with the mt genomes of diverse freshwater mussel species. The complete F and M mt genomes of S. carinatus are 16716 bp and 17102 bp in size, respectively. The F and M mt genomes of S. carinatus diverge by about 40% in nucleotide sequence and 48% in amino acid sequence. Compared to F counterparts, the M genome shows a more compact structure. Different gene arrangements are found in these two gender-associated mt genomes. Among these, the F genome cox2-rrnS gene order is considered to be a genome-level synapomorphy for female lineage of the subfamily Gonideinae. From maternal and paternal mtDNA perspectives, the phylogenetic analyses of Unionoida indicate that S. carinatus belongs to Gonideinae. The F and M clades in freshwater mussels are reciprocal monophyly. The phylogenetic trees advocate the classification of sampled Unionidae species into four subfamilies: Gonideinae, Ambleminae, Anodontinae, and Unioninae, which is supported by the morphological characteristics of glochidia.
Advertisement call of Scinax littoralis and S. angrensis (Amphibia: Anura: Hylidae), with notes on the reproductive activity of S. littoralis
Michel V. Garey,Thais R.N. Costa,André M.X. de Lima,Luís F. Toledo
Acta Herpetologica , 2012,
Abstract: Scinax littoralis and S. angrensis are poorly known Atlantic forest endemic species from the Scinax catharinae group, which is known from southern and southeastern Brazil. Herein, we describe the advertisement calls of these two species and compare them to other species within the S. catharinae group. Additionally, we provide information on breeding sites, and calling activity in S. littoralis. Advertisement calls of S. angrensis and S. littoralis are composed of multi-pulsed notes with multiple frequency bands and frequency modulation. Scinax littoralis has a higher minimum and maximum frequency, and lower dominant frequency than S. angrensis, while Scinax littoralis has a longer call. Scinax littoralis appears to be a habitat generalist, occurring from secondary to mature forests, and breeding both in temporary and in permanent ponds. Male S. littoralis were usually observed calling perched on shrub stems, and displayed satellite behavior when the male density was high.
Morphological study of the pineal gland of (crab eater raccoon) Procyon cancrivorus (Cuvier, 1798)
Leandro de Oliveira Marques,Ana Flávia de Carvalho,Ana Carolina Furlanetto Man?anares,Celina Almeida Furlanetto Man?anares
Biotemas , 2010,
Abstract: The Procyon cancrivorus is a wild carnivore that is widely distributed and relatively common, but it remains little studied, and few works report on the biology of this species. The aim of this work was to characterize morphologically the pineal gland of Procyon cancrivorus through macro, microscopic and radiographic studies, and to compare them with those from other animals. In this work, four adult animals of both sexes were used, originating from the Scientific Herd of CECRIMPAS IBAMA (Process no 02027.003731/04-76). Macroscopically, the pineal gland of Procyon cancrivorus was located between the occipital lobes of the cerebral hemispheres, cranially to the vermis cerebelar. It was positioned rostrally to the rostral colliculus and caudally to the habenular comissure. Microscopically, the gland was covered externally by a capsule deriving from the meningeal pia mater. The presence of three types of cells was noted in the glandular parenchyma: pinealocytes, glial cells and mast cells. No calcareous concretions in the pineal gland were found in the radiographic and microscopic studies.
MORFOLOGIA DOS MúSCULOS DA COXA DE M O-PELADA (Procyon cancrivorus) – Cuvier 1798  [cached]
Firmino Cardoso Pereira,Vanessa Morais Lima,Kleber Fernando Pereira
Ciência Animal Brasileira , 2010,
Abstract: The Procyon cancrivorus is a wild animal, which belongs to the carnivore order, present in all Brazilian territory, some Central American countries, Uruguay and Argentina. Although this animal is not in the list of endangered species, there are few morphological data about this species. Only studies about the habits,habitat and some morphological data were found in Brazilian and world literature. The purpose of this study was to describe the proximal and distal insertions of the posterior and medial thigh muscles of the P. cancrivorus, comparing them with domestic carnivores literature data, such as dogs and cats. The five specimens were collected postmortem, victims of accidents on highways. The animals were fixed in formaldehyde (10%) and stored in opaque covered tanks. The description of the thigh musculature was made possible by the dissection technique, visualizing its proximal and distal insertions, irrigation and innervation. The results were documentedwith a digital camera and compared with literature data of the thigh muscles of domestic animals such as cats and dogs. Studies on the quadriceps femoris, sartorius, tensor fascia lata, bicepsfemoris, semitendinosus, adductor, semimembranosus, caudal crural abductor, twins, quadratus femoris, gracilis and pectineus were carried out and great similarity with the thigh muscles of carnivores such as cats and dogs were found.
Rethinking Republicanism in Switzerland during 1798-1801  [cached]
Antoine Broussy
La Révolution Fran?aise : Cahiers de l’Institut d’Histoire de la Révolution Fran?aise , 2011,
Abstract: A partir de 1798, la Suisse entre en révolution. Toutefois, la notion de révolution est rapidement controversée et assimilée à la violence destructrice ainsi qu’à la perte d’indépendance et de neutralité du pays. L’étude des débats constitutionnels qui se succèdent en Suisse entre 1798 et 1801 est l’occasion d’aborder le jeu des relations complexes qui se nouent entre la notion de rupture et celle de continuité. Je propose ici de montrer comment les élites politiques de tous bords prétendent se forger une légitimité en inscrivant leur discours et leur action dans la continuité de l’histoire nationale . En cherchant ainsi à placer leurs pas dans les traces du passé, la rupture créée par la Révolution tend à être dévalorisée et interprétée de fa on négative par les acteurs eux-mêmes. Cette lecture à chaud de l’événement donne par la suite naissance à un biais historiographique par lequel la portée de la République helvétique est dépréciée pour longtemps dans l’histoire de la Suisse.
Mate recognition and reproductive isolation in the sibling species Spodoptera littoralis and Spodoptera litura  [PDF]
Ahmed M. Saveer,Paul G. Becher,G?ran Birgersson,Bill S. Hansson,Peter Witzgall,Marie Bengtsson
Frontiers in Ecology and Evolution , 2014, DOI: 10.3389/fevo.2014.00018
Abstract: Mate recognition is crucial for reproductive isolation and for maintaining species integrity. Chemosensory-mediated sexual communication with pheromones is an essential component of mate recognition in moths. Confronted with sex pheromone stimuli released from conspecific and closely related heterospecific females, which partially overlap in chemical composition, male moths are under strong selection to recognize compatible mates. Here, we investigated the role of pheromone signals in premating communication in the sibling species Spodoptera littoralis and S. litura (Lepidoptera, Noctuidae). Further, we measured the reproductive consequence of conspecific vs. heterospecific matings. Both species use Z9,E11–14:Ac as the major pheromone compound, and the 11-component blend found in pheromone glands of S. littoralis comprises the compounds found in S. litura. Accordingly, S. littoralis and S. litura males readily responded to conspecific and heterospecific calling females in no-choice behavioral tests. In contrast, in a dual-choice test, S. littoralis males choose conspecific calling females, whereas S. litura males did not discriminate between conspecific and heterospecific females. In S. littoralis females, heterospecific matings had a negative fitness effect as compared to conspecific matings. Female longevity, egg-laying and hatching of larvae were significantly reduced by matings with heterospecific males. Reciprocal crossings, between S. litura females and S. littoralis males, were prevented by genital morphology, which is consistent with reduced heterospecific attraction of S. littoralis males in a dual-choice assay. On the other hand, matings between S. littoralis females and S. litura males, under a no-choice situation, show that interspecific matings occur in zones of geographical overlap and corroborate the idea that mate quality, in these closely related species, is a continuous and not a categorical trait.
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