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1.
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Banded chromosomes of five species of testudinid turtles (Geochelone pardalis, G. elongata, G. elephantopus, Gopherus berlandieri, and G. polyphemus) reveal little variation within either genus, although there are differences in amount and distribution of heterochromatin between Geochelone pardalis and G. elongata. The chromosomal position and size of the nucleolar-organizer region differs between species of the two genera.Comparisons of standard karyotypes of these species and Malacochersus tornieri with data in the literature on other tortoises show a diploid number of 52 characterizes the family. These data are consistent with those for other families which show turtles are karyotypically conservative. G-banded chromosomes of Geochelone are identical to those of Chinemys reevesi, a karyotypically primitive batagurine emydid, supporting a derivation of the tortoises from a batagurine ancestor.  相似文献   

3.
We examine the phylogeography, phylogeny and taxonomy of hinge‐back tortoises using a comprehensive sampling of all currently recognized Kinixys species and subspecies and sequence data of three mitochondrial DNA fragments (2273 bp: 12S rRNA, ND4 + adjacent DNA coding for tRNAs, cytb) and three nuclear loci (2569 bp: C‐mos, ODC, R35). Combined and individual analyses of the two data sets using Bayesian and Maximum Likelihood methods suggest that the savannah species of Kinixys are paraphyletic with respect to the rainforest species K. homeana and K. erosa, and that the rainforest species may be derived from a savannah‐living ancestor. The previously recognized savannah species K. belliana was a conglomerate of three deeply divergent clades that we treat here as distinct species. We restrict the name K. belliana (Gray, 1830) to hinge‐back tortoises ranging from Angola to Burundi, while five‐clawed hinge‐back tortoises from the northernmost part of the formerly recognized range of K. belliana, together with four‐clawed tortoises from West Africa, are assigned to the species K. nogueyi (Lataste, 1886). These two species are allied to K. spekii, whereas Southeast African and Malagasy hinge‐back tortoises formerly lumped together with K. belliana represent the distinct species K. zombensis Hewitt, 1931, which is sister to K. lobatsiana. The latter two species together constitute the sister group of the rainforest species K. homeana and K. erosa. Mitochondrial data suggest that K. natalensis has a basal phylogenetic position in a clade embracing K. belliana sensu stricto, K. nogueyi and K. spekii, while nuclear data and the two data sets combined favour a sister group relationship of K. natalensis to all other hinge‐back tortoises. Phylogeographic structure is present in all wide‐ranging species and correlates in K. homeana and K. erosa with the Dahomey Gap and former rainforest refugia. The Malagasy population of K. zombensis is weakly differentiated from its South African conspecifics and further sampling is needed to determine whether there is support for the subspecific distinctness of Malagasy tortoises.  相似文献   

4.
The conservation of tortoises poses a unique situation because several threatened species are commonly kept as pets within their native ranges. Thus, there is potential for captive populations to be a reservoir for repatriation efforts. We assess the utility of captive populations of the threatened Agassiz’s desert tortoise (Gopherus agassizii) for recovery efforts based on genetic affinity to local areas. We collected samples from 130 captive desert tortoises from three desert communities: two in California (Ridgecrest and Joshua Tree) and the Desert Tortoise Conservation Center (Las Vegas) in Nevada. We tested all samples for 25 short tandem repeats and sequenced 1,109 bp of the mitochondrial genome. We compared captive genotypes to a database of 1,258 Gopherus samples, including 657 wild caught G. agassizii spanning the full range of the species. We conducted population assignment tests to determine the genetic origins of the captive individuals. For our total sample set, only 44 % of captive individuals were assigned to local populations based on genetic units derived from the reference database. One individual from Joshua Tree, California, was identified as being a Morafka’s desert tortoise, G. morafkai, a cryptic species which is not native to the Mojave Desert. Our data suggest that captive desert tortoises kept within the native range of G. agassizii cannot be presumed to have a genealogical affiliation to wild tortoises in their geographic proximity. Precautions should be taken before considering the release of captive tortoises into the wild as a management tool for recovery.  相似文献   

5.
A taxonomic review of Korean Haliplidae Aubé is presented. Eight species in two genera are recognized, one of which (Haliplus diruptus Balfour‐Browne) is reported for the first time in South Korea. We also found that H. ovalis Sharp previously recorded in the Korean peninsula was an incorrect identification of H. chinensis Falkenström. Habitus and scanning electron microscopy (SEM) photographs, diagnoses of genera, additional characters of species and diagnostic characters with illustrations of the species are provided.  相似文献   

6.
The Glyptodontidae is one of the most conspicuous groups in the Pleistocene megafauna of the Americas. The Glyptodontinae were involved in the Great American Biotic Interchange (GABI) and their earliest records in North America are about 3.9 Ma, suggesting an earlier formation of the Panamanian landbridge. Taxonomically it is possible to recognize two Pleistocene genera of Glyptodontinae:Glyptodon (ca. 1.8 – 0.008 Ma), restricted to South America, andGlyptotherium (ca. 2.6 – 0.009 Ma), including records in both North and Central America. Here we present the first report of the genusGlyptotherium in South America, from the Late Pleistocene of several fossil localities in Falcón State, northwestern Venezuela. A comparative analysis of the material, represented by cranial and postcranial parts, including the dorsal carapace and caudal rings, suggests a close affinity withGlyptotherium cylindricum (Late Pleistocene of Central Mexico). This occurrence in the latest Pleistocene of the northernmost region of South America Supports the bidirectional faunal migration during the GABI and the repeated re-immigration from North America of South American clades, as has been reported in other members of the Cingulata (e.g., Pampatheriidae).   相似文献   

7.
The growth and weight development of Leopard tortoise hatchings (Geochelone pardalis) kept at the Al Wabra Wildlife Preservation (AWWP), Qatar, was observed for more than four years, and compared to data in literature for free‐ranging animals on body weight or carapace measurements. The results document a distinctively faster growth in the captive animals. Indications for the same phenomenon in other tortoise species (Galapagos giant tortoises, G. nigra; Spur‐thighed tortoises, Testudo graeca; Desert tortoises, Gopherus agassizi) were found in the literature. The cause of the high growth rate most likely is the constant provision with highly digestible food of low fiber content. Increased growth rates are suspected to have negative consequences such as obesity, high mortality, gastrointestinal illnesses, renal diseases, “pyramiding,” fibrous osteodystrophy or metabolic bone disease. The apparently widespread occurrence of high growth rates in intensively managed tortoises underlines how easily ectothermic animals can be oversupplemented with nutrients. Zoo Biol 29:517–525, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

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Lepidaploa belongs to tribe Vernonieae, one of the most complex tribes of Asteraceae, and the relationships within Lepidaploa and among related genera are poorly understood. Microcharacters may be of taxonomic value and may be used in the identification of taxa at different ranks. To evaluate the reliability of microcharacters as taxonomic markers in this group, we analysed the micromorphology of phyllaries, florets and cypselae in detail in 23 species of Lepidaploa .The species were studied using stereo, light, and scanning electron microscopy. Eight trichome types (eglandular and glandular) were observed on phyllaries, florets and cypselae, in addition to crystals, idioblasts and other microstructures. The results demonstrates that the ocurrence of different combinations of trichome types and crystals, presence of a stylar basal node, idioblasts and glandular apical anther appendages are highly useful to differentiate between related species of Lepidaploa and a diagnostic key using these characters is presented. However, these characters are not of much use to distinguish between closely related genera of Vernonieae since most characters appear homeoplasic and are found in representatives of different genera.  相似文献   

10.
Tetramesa romana is a biological control agent of the giant reed, Arundo donax (Poaceae: Arundinoideae), which is an invasive weed in the riparian habitats of the Rio Grande Basin of Texas, the southwestern U.S.A. and northern Mexico. Field evaluations were conducted in the native range of T. romana in Mediterranean Europe and in the introduced ranges of Texas, California, and South Africa to compare densities of the wasp. Population densities and percentage parasitism levels for the 2017 year are compared to meteorological variables (average temperature, precipitation, and heat units). In the introduced ranges of Texas (intentional) and South Africa (adventive) T. romana population densities were 39 and 10-fold higher than in the native range, respectively. Percentage parasitism of T. romana in Texas and in the native range of Thessaloniki, Greece were 2.0% and 34.3%, respectively. Annual heat unit accumulation was 1.3–2.7-fold higher at Texas sites than at other introduced or native sites, and heat units were positively associated with exit hole counts at introduced sites. Annual precipitation was 2-fold higher at Texas and South African sites than in California and the native range sites. Favourable weather conditions and reduced parasitism in Texas along the Rio Grande, as compared to the native range, allows T. romana to reach higher population levels and cause considerable damage to A. donax.  相似文献   

11.
Glyptodon and Glyptotherium represent the most conspicuous taxa of late Neogene and Pleistocene glyptodonts in South America and North America, respectively. The earliest records of Glyptodon in South America are 1.07 Ma (late early Pleistocene, Calabrian), although the possibility that “Paraglyptodon uquiensis” represents a Pliocene specimen of Glyptodon cannot be rejected. Glyptotherium originated from South American ancestry in northern South America or Central America about 3.9 Ma (early late Pliocene, Zanclean) or earlier. The diversity of South American Glyptodon is currently under study, but preliminary evidence would indicate that no more than three species (G. munizi, G. elongatus and G. reticulatus) are valid, plus a possible new Andean species. In turn, according to the updated taxonomy proposed herein, Glyptotherium includes two chronospecies. The earliest species, Gl. texanum, differs only slightly from the latest species, Gl. cylindricum. The relationship of Glyptodon and Glyptotherium has been problematical since the discovery of the North American lineage, at first identified as various species of Glyptodon and later considered a separate genus. Glyptodon is recognized as a natural group and recent taxonomic and phylogenetic revisions place all North American glyptodontines into Glyptotherium. In this paper, we propose a detailed morphological comparison between the southern South American species of Glyptodon and Glyptotherium in order to identify diagnostic differences and potential synapomorphies. Both genera can be distinguished mainly by differences in the skull, mandible, dentition, dorsal carapace, and caudal armor, Glyptodon being somewhat larger than Glyptotherium. Both clades show a highly conservative evolution, which could be interpreted as an anagenesis. The scarce records of glyptodonts in Central America show more morphological affinity with Glyptotherium than with Glyptodon.  相似文献   

12.
The Upper Pleistocene/Lower Holocene fossil-bearing sites of the Serra da Capivara National Park Region have yielded three cervid species: Mazama gouazoubira, M. americana and Blastocerus dichotomus, all currently living in South America, the two first in the region. A grand total of more than one hundred remains demonstrates the presence of Mazama gouazoubira in seven sites, mainly the Toca das Moendas, the Toca do Serrote do Artur, the Toca da Cima dos Pilão. This small species shows, since the Upper Pleistocene, a conspicuous tendency to reduce the average dimensions of its teeth and long bones. From the taller M. americana, only a dozen of remains were found in four sites, mainly the Sitio do Meio. In all of these it is sympatric with M. gouazoubira. It differs from this last one by its cheek teeth and its limb bones size and proportions. The oldest site where the species is known is Tarija (Bolivia, Middle Pleistocene) and it does not show any significant changes in size and proportions between recent and fossil samples. Sixteen remains of the large B. dichotomus were found in five sites, mainly the Toca das Moendas and the Toca da Barra do Antonião. The species is a rare fossil, but is frequently figured in the rock art painting of the region, where it is presently unknown.  相似文献   

13.
A landscape-scale assessment of how bobwhite productivity varies in relation to weather does not exist for northern bobwhite (Colinus virginianus). We collected age and sex ratio and body mass data from hunter-harvested bobwhites in 16 counties of South Texas (n = 72,797 bobwhites) during 2001–2009 hunting seasons. We evaluated annual bobwhite production (juvenile:adult age ratios) as a function of cumulative April–August rainfall using National Oceanic and Atmospheric Administration (NOAA) weather station data from Falfurrias and Hebbronville, Texas. We observed minimal among-year change in percent males harvested (51.0–54.5% male) and mean mass (156–160 g) of bobwhites across South Texas. We found no relationship between percent male or body mass and weather. We documented a positive, linear relationship between cumulative April–August rainfall and bobwhite age ratios (r2 = 0.94); we also documented a negative, linear relationship between summer (Jun–Aug) mean maximum daily temperature and bobwhite age ratios (r2 = 0.38). Our results suggest that rainfall is a landscape-scale indicator of annual bobwhite production in South Texas and can thus be used to manage annual expectations of quail hunters prior to the hunting season. © The Wildlife Society, 2012  相似文献   

14.
Nomenclatural confusion has existed within the Mylodontinae for several genera, and has resulted in the supposition that Paramylodon of North America is synonymous with Glossotherium of South America. A taxonomic revision of crania for Glossotherium and Paramylodon upholds their separation as distinct genera and provides a list of diagnostic characters that have been lacking. Assessment was made using principal components analysis for suites of cranial and mandibular measurements, evaluation of ratios and measurement distribution, and by examining qualitative characters. Results show the greatest characterization for the skull comes from differences relating to cranial length versus width, whereas the mandible is predominantly distinguished by qualitative characters of the predental spout. Examination of the Pliocene species Glossotherium chapadmalense from South America shows a combination of characters indicative of each genus, but exhibits more with Glossotherium and is tentatively retained under that genus. The mix of characters indicates that G. chapadmalense is the likely ancestor to Paramylodon, although when and where the transition took place is still unclear. During the evolutionary transition, Paramylodon crania emphasized an increase in length of the palate, whereas those of Glossotherium emphasized an increase in cranial width. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 885–903.  相似文献   

15.
Skeletal remains of baleen whales killed during the onset of 20th century commercial whaling lie scattered across the shores and abandoned whaling stations of the subantarctic island of South Georgia. Here we report on genetic species identification of whale bones collected from South Georgia using standard historical DNA protocols. We amplified and sequenced short fragments of the mitochondrial DNA (mtDNA) control region from 281 available bone samples. Of these, 231 provided mtDNA sequences of sufficient quality and length (174–194 bp) for species identification: 158 bones were identified as humpback whale (Megaptera novaeangliae), 51 bones were identified as fin whale (Balaenoptera physalus), 18 bones were identified as blue whale (B. musculus), two bones were identified as sei whale (B. borealis), one bone was identified as a southern right whale (Eubalaena australis), and one bone was identified as a southern elephant seal (Mirounga leonina). The prominence of humpback, fin, and blue whale bones in the sample collection corresponds to the catch record of the early years of whaling on the island of South Georgia (pre‐1915), prior to the depletion of these populations.  相似文献   

16.
《Journal of bryology》2013,35(4):360-362
Abstract

The family Sematophyllaceae is a difficult family to treat in Africa because of the large number of species described without any subsequent revision or monography and, despite the many collections mentioned in this paper, only two species had previously been identified from Malawi. A total of four species in four genera (Gammiella, Mρacrohymenium, Radulina and Wijkia) are recorded in this paper, all but one new to Malawi. The two remaining genera (Sematophyllum and Trichosteleum) present additional difficulties of identification, and will be dealt with separately.  相似文献   

17.
Galapagos giant tortoises (Chelonoidis spp.) are a group of large, long-lived reptiles that includes 14 species, 11 of which are extant and threatened by human activities and introductions of non-native species. Here, we evaluated the phylogenetic relationships of all extant and two extinct species (Chelonoidis abingdonii from the island of Pinta and Chelonoidis niger from the island of Floreana) using Bayesian and maximum likelihood analysis of complete or nearly complete mitochondrial genomes. We also provide an updated phylogeographic scenario of their colonization of the Galapagos Islands using chrono-phylogenetic and biogeographic approaches. The resulting phylogenetic trees show three major groups of species: one from the southern, central, and western Galapagos Islands; the second from the northwestern islands; and the third group from the northern, central, and eastern Galapagos Islands. The time-calibrated phylogenetic and ancestral area reconstructions generally align with the geologic ages of the islands. The divergence of the Galapagos giant tortoises from their South American ancestor likely occurred in the upper Miocene. Their diversification on the Galapagos adheres to the island progression rule, starting in the Pleistocene with the dispersal of the ancestral form from the two oldest islands (San Cristóbal and Española) to Santa Cruz, Santiago, and Pinta, followed by multiple colonizations from different sources within the archipelago. Our work provides an example of how to reconstruct the history of endangered taxa in spite of extinctions and human-mediated dispersal events and provides a framework for evaluating the contribution of colonization and in situ speciation to the diversity of other Galapagos lineages.  相似文献   

18.
Aim Heterophylly is present in many plant species on oceanic islands. Almost all of these plants are island endemics, and heterophylly may have evolved as a response to feeding from large insular browsers such as giant tortoises and flightless birds. We tested this anti‐browser hypothesis by feeding Aldabra giant tortoises (Geochelone gigantea) with leaves of native Mauritian plants to see if they distinguished between juvenile and adult leaves and between heteophyllous and homophyllous species. Location Mauritius. Methods In a choice experiment we recorded feeding response of four captive Aldabra giant tortoises to 10 species of Mauritian plants, of which seven were heterophyllous and three homophyllous. Results In general, juvenile leaves of heterophyllous species showed convergence in shape and midrib coloration. Homophyllous foliage was preferred to heterophyllous, and among heterophyllous species adult foliage was preferred to juvenile. Main conclusions Several Mascarene heterophyllous plants show convergence in morphology of juvenile leaves and these are avoided by giant tortoises. This indicates a strong selection history from large browsers such as the giant tortoises. The Mascarene example is in accordance with several other comparable cases of plant‐large browser interactions from other archipelagos.  相似文献   

19.
Lepidosirenidae is a clade of freshwater lungfishes that include the extant South American Lepidosiren paradoxa Fitzinger, 1837 and African species of the genus Protopterus. These genera have been geographically separated since the break‐up of Gondwana in the Early Cretaceous, but they display similar biology and morphology. Species were distinguished by a combination of features such as head‐to‐body ratios, the number of pairs of ribs, and the presence of external gills, but no discrete skeletal characters were identified, and no comparative studies including all extant species have been published. I used computed tomography (CT), X‐ray photography, and specimens from museum collections to describe the skeletal morphology of all species of lepidosirenid in a comparative context. I digitally disarticulated the bones in each specimen to compile a comparative atlas of the cranial and pectoral elements of all extant lungfishes, which has the potential to increase the correct identifications of specimens in museum collections. The morphology of the frontoparietal, parasphenoid, supraorbital, and suboperculum differ between species. I used those characters, along with molecular sequence data from the ribosomal RNA gene 16S, to run combined morphological and molecular phylogenetic analyses. Lepidosirenidae is monophyletic in all analyses, but the interrelationships of the species of Protopterus vary with the different sources of character data. © 2015 The Linnean Society of London  相似文献   

20.
A nearly complete skeleton of a juvenile sauropod from the Lower Morrison Formation (Late Jurassic, Kimmeridgian) of the Howe Ranch in Bighorn County, Wyoming is described. The specimen consists of articulated mid-cervical to mid-caudal vertebrae and most appendicular bones, but cranial and mandibular elements are missing. The shoulder height is approximately 67 cm, and the total body length is estimated to be less than 200 cm. Besides the body size, the following morphological features indicate that this specimen is an early juvenile; (1) unfused centra and neural arches in presacral, sacral and first to ninth caudal vertebrae, (2) unfused coracoid and scapula, (3) open coracoid foramen, and (4) relatively smooth articular surfaces on the limb, wrist, and ankle bones. A large scapula, short neck and tail and elongate forelimb bones relative to overall body size demonstrate relative growth. A thin-section of the mid-shaft of a femur shows a lack of annual growth lines, indicating an early juvenile individual possibly younger than a few years old. Pneumatic structures in the vertebral column of the specimen SMA 0009 show that pneumatisation of the postcranial skeleton had already started in this individual, giving new insights in the early ontogenetic development of vertebral pneumaticity in sauropods.

The specimen exhibits a number of diplodocid features (e.g., very elongate slender scapular blade with a gradually dorsoventrally expanded distal end, a total of nine dorsal vertebrae, presence of the posterior centroparapophyseal lamina in the posterior dorsal vertebrae). Although a few diplodocid taxa, Diplodocus, cf. Apatosaurus, and cf. Barosaurus, are known from several fossil sites near the Howe Ranch, identification of this specimen, even at a generic level, is difficult due to a large degree of ontogenetic variation.  相似文献   

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