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Ernesto Capanna - One of the best experts on this subject based on the ideXlab platform.
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The chromosomes of Rodents of the Republic of Benin (West Africa): 2. Sciuridae and Thryonomyidae
Rendiconti Lincei, 1996Co-Authors: Maria Vittoria Civitelli, Jean T. Claude Codjia, Ernesto CapannaAbstract:The karyotype has been studied in 2 species of Rodents, the Redless squirrelFunisciurus anerythrus (Sciurognathi, Sciuridae) and the Cane ratThryonomys swinderianus (Hystricognathi, Thryonomyidae), from crop lands and woodlands of the Republic of Benin (West Africa). Chromosomes were obtained by bone marrow method and stained both by standard Giemsa and NOR banding procedures. T.swinderianus shows a2n = 44 (NF = 86) complement. Chromosomes are all biarmed except for one pair acrocentrics. Nuclear Organising Regions (NORs) are located on one submetacentric pair coinciding with a secondary constriction.F. anerythrus shows a2n = 38 (NF = 62) complement. The karyotype is composed of 7 acrocentric chromosomal pairs and 12 biarmed chromosomal pairs. The karyotype morphology of the species was discussed within the context of Old World Hystricognathi and African Sciuridae comparative cytogenetics.
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The chromosomes of Rodents of the Republic of Benin (West Africa): 2. Sciuridae and Thryonomyidae
Rendiconti Lincei, 1996Co-Authors: Maria Vittoria Civitelli, Jean T. Claude Codjia, Ernesto CapannaAbstract:The karyotype has been studied in 2 species of Rodents, the Redless squirrel Funisciurus anerythrus (Sciurognathi, Sciuridae) and the Cane rat Thryonomys swinderianus (Hystricognathi, Thryonomyidae), from crop lands and woodlands of the Republic of Benin (West Africa). Chromosomes were obtained by bone marrow method and stained both by standard Giemsa and NOR banding procedures. T. swinderianus shows a 2n = 44 ( NF = 86) complement. Chromosomes are all biarmed except for one pair acrocentrics. Nuclear Organising Regions (NORs) are located on one submetacentric pair coinciding with a secondary constriction. F. anerythrus shows a 2n = 38 ( NF = 62) complement. The karyotype is composed of 7 acrocentric chromosomal pairs and 12 biarmed chromosomal pairs. The karyotype morphology of the species was discussed within the context of Old World Hystricognathi and African Sciuridae comparative cytogenetics. E stato studiato il cariotipo di due specie di Roditori, provenienti da biotopi forestali e da coltivi del Benin méridionale (Africa Occidentale): lo Sciurognato Funisciurus anerythrus e l’lstricognato Thryonomys swinderianus. I cromosomi sono stati ottenuti attraverso la comune tecnica da midollo rosso délie ossa e colorati sia con la procedura standard con Giemsa, sia con tecniche di bandeggio (AgNOR). T. swinderianus présenta 2n = = 44 e NF = 86. I cromosomi sono tutti a due braccia tranne una coppia che è di morfologia acrocentrica. Le Regioni Nucleolo Organizzatrici (NOR) sono localizzate, in corrispondenza di una costrizione secondaria, in una sola coppia di submetacentrici. F. anerythrus mostra 2n = 38 e NF = 62. Il cariotipo è formato da 7 coppie di cromosomi acrocentrici e da 12 coppie di cromosomi a due braccia. I dati sono stati discussi nell’ambito della cariologia degli Istricognati del vecchio mondo e degli Sciuridi d’Africa.
Wilma Wessels - One of the best experts on this subject based on the ideXlab platform.
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early and middle miocene Sciuridae mammalia rodentia from anatolia turkey
Journal of Vertebrate Paleontology, 2018Co-Authors: A A Bosma, Hans De Bruijn, Wilma WesselsAbstract:ABSTRACTIsolated cheek teeth of Sciuridae (Mammalia, Rodentia) from 15 early and middle Miocene localities in Anatolia (Turkey) are described. The localities range in age from local zone B to local...
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late miocene Sciuridae mammalia rodentia from anatolia turkey
Journal of Vertebrate Paleontology, 2013Co-Authors: A A Bosma, Hans De Bruijn, Wilma WesselsAbstract:Isolated cheek teeth of Sciuridae (Rodentia, Mammalia) from nine late Miocene localities in central Anatolia (Turkey) are described. The teeth represent at least 12 different species, five of which belong to the ground squirrel genus Tamias, two to the ground squirrel genus Spermophilinus, one to the flying squirrel genus Hylopetes, and two to the flying squirrel genus Pliopetaurista. One species, Tamias anatoliensis (type locality Altintas 1), is new. An unknown genus and species of giant tree or ground squirrel is represented by one tooth. Two teeth probably form the oldest record in western Eurasia of the tree squirrel genus Sciurus. Seven of the localities that yielded Sciuridae are lacustrine deposits, two are karst fissure fills. Their estimated ages range from MN 9 to MN 13. The majority of late Miocene Sciuridae from Anatolia show affinities with European sciurids of the same period.
John L Koprowski - One of the best experts on this subject based on the ideXlab platform.
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tamiasciurus mearnsi rodentia Sciuridae
Mammalian Species, 2016Co-Authors: John L Koprowski, Michael A Steele, Nicolas RamoslaraAbstract:Tamiasciurus mearnsi ([Townsend, 1897][1]) is a small-sized tree squirrel commonly called Mearns’s squirrel. One of 3 species that comprise the genus Tamiasciurus , T. mearnsi , is endemic to the Sierra de San Pedro Martir in Baja California, Mexico; it is considered rare and occurs only at low densities. T. mearnsi is federally listed as “Threatened” in Mexico and is also included in the International Union for the Conservation of Nature and Natural Resources Red List of Threatened Species as “Endangered.” The introduction of the eastern gray squirrel ( Sciurus carolinensis ) may be a serious threat to this relict species. [1]: #ref-46
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microsciurus flaviventer rodentia Sciuridae
Mammalian Species, 2016Co-Authors: Timothy G Jessen, Allyssa L Kilanowski, Nathan R Gwinn, Melissa J Merrick, John L KoprowskiAbstract:Microsciurus flaviventer ([Gray, 1867][1]) is a Neotropical tree squirrel commonly known as the Amazon dwarf squirrel. Small bodied with dark brown dorsal pelage contrasted with a gray or yellowish gray venter, and a faintly banded tail. M. flaviventer is 1 of 4 species in the genus Microsciurus . The geographic range of M. flaviventer extends from the Amazon basin of South America throughout western and southeastern Colombia, Ecuador, southern Peru, Brazil west of Rio Negro, and Madeira. It is most commonly associated with evergreen lowland tropical rainforest. Status of M. flaviventer is “Data Deficient” under the International Union for Conservation of Nature and Natural Resources Red List of Threatened Species ; however, loss of habitat is a major concern. [1]: #ref-18
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Sciurus anomalus (Rodentia: Sciuridae)
Mammalian Species, 2016Co-Authors: John L Koprowski, Leah Gavish, Sandra L. DoumasAbstract:Sciurus anomalus [Guldenstadt, 1785][1] is a rodent commonly called the Caucasian squirrel. S. anomalus is a medium-sized squirrel with chestnut gray to grizzled buff dorsum, buff eye rings, and chestnut to buff-yellow underparts. S. anomalus is 1 of 28 species in the genus Sciurus and is found in forests of the Middle East and extreme southwestern Asia. The International Union for Conservation of Nature and Natural Resources considers S. anomalus to be a species of “Least Concern;” habitat destruction is the main threat. [1]: #ref-45
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sciurus ignitus rodentia Sciuridae
Mammalian Species, 2014Co-Authors: Melissa J Merrick, Shari L Ketcham, John L KoprowskiAbstract:Abstract: Sciurus ignitus (Gray, 1867) is a Neotropical tree squirrel commonly known as the Bolivian squirrel. It is a small-bodied, understory and mid-canopy dweller that occurs within the evergreen lowland and montane tropical rain forests along the eastern slope of the Andes in Peru, Bolivia, and extreme northern Argentina, and the western Amazon Basin in Brazil and Peru between 200 and 2,700 m in elevation. S. ignitus is 1 of 28 species in the genus Sciurus, and 1 of 8 in the subgenus Guerlinguetus. The taxonomic status of this species, as with other small sciurids in Peru and Bolivia, remains ambiguous. S. ignitus is currently listed as “Data Deficient” by the International Union for Conservation of Nature and Natural Resources.
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spermophilus citellus rodentia Sciuridae
Mammalian Species, 2014Co-Authors: Nicolas Ramoslara, John L Koprowski, Boris Krystufek, Ilse E HoffmannAbstract:Spermophilus citellus (Linnaeus, 1766) is a medium-sized sciurid commonly called the European ground squirrel. The species inhabits grasslands in central and southeastern Europe on a range from short-grass steppes to meadow orchards, and from sea level to an elevation of 2,500 m. These squirrels live in colonies and construct burrows used for hibernation, reproduction, refuge, and resting. Due to serious declines in many portions of its range, the species is listed as “Vulnerable” by the International Union for Conservation of Nature and Natural Resources. It is also protected by the Bern Convention (Appendix II), and the European Union Habitats and Species Directive (Annexes II and IV).
David W Coltman - One of the best experts on this subject based on the ideXlab platform.
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sexing the Sciuridae a simple and accurate set of molecular methods to determine sex in tree squirrels ground squirrels and marmots
Molecular Ecology Resources, 2012Co-Authors: Jamieson C Gorrell, Stan Boutin, Shirley Raveh, Peter Neuhaus, Steeve D Cote, David W ColtmanAbstract:: We determined the sequence of the male-specific minor histocompatibility complex antigen (Smcy) from the Y chromosome of seven squirrel species (Sciuridae, Rodentia). Based on conserved regions inside the Smcy intron sequence, we designed PCR primers for sex determination in these species that can be co-amplified with nuclear loci as controls. PCR co-amplification yields two products for males and one for females that are easily visualized as bands by agarose gel electrophoresis. Our method provides simple and reliable sex determination across a wide range of squirrel species.
Cliff A. Lemen - One of the best experts on this subject based on the ideXlab platform.
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A simple morphological predictor of bite force in rodents
Journal of Zoology, 2008Co-Authors: P. W. Freeman, Cliff A. LemenAbstract:Bite force was quantified for 13 species of North American rodents using a piezoresistive sensor. Most of the species measured (11) formed a tight relationship between body mass and bite force (log 10(bite force)=0.43(log 10(body mass))+0.416; R240.98). This high correlation exists despite the ecological (omnivores, grazers and more carnivorous) and taxonomic (Cricetidae, Heteromyidae, Sciuridae and Zapodidae) diversity of species. Two additional species, Geomys bursarius (Geomyidae) and a Sciurus niger (Sciuridae), bit much harder for their size. We found a simple index of strength based on two measurements of the incisor at the level of the alveolus (Zi=((anterior-posterior length)2(medial-lateral width))/6) that is highly predictive of bite force in these rodents (R240.96). Zi may be useful for prediction of bite force (log10 (Bite Force)=0.566log10 (Zi)+1.432) when direct measurements are not available.
