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Despite recent taxonomic evaluations of Mephitidae and North American hog‐nosed skunks, southern South American species of Conepatus have not been thoroughly examined in a systematic context. Conepatus chinga and Conepatus humboldtii were described more than 150 years ago, based on external characters such as hair coloration and size. Although historically recognized as valid species, to date no detailed systematic analysis has been performed for either of these taxa. Herein, we evaluated the taxonomic status of C. chinga and C. humboldtii within the southern part of South America using geometric morphometrics of the skull and mandible, mitochondrial DNA analysis using the cytochrome b and cytochrome oxidase c subunit I genes, and also control region and pelage pattern variation. We failed to find morphological (skull shape and pelage coloration patterns) or molecular differences between these two species; thus, we considered that the specimens assigned to C. chinga and C. humboldtii belong to the same species. Our results indicate that environmental variation seems to be responsible for shape and size variation in Conepatus skulls from southern South America. © 2013 The Linnean Society of London  相似文献   

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A fossil skull, Stw 53, from the Plio/Pleistocene of Sterkfontein, in South Africa, has been referred toHomo habilis Leakey, Napier, andTobias, 1964. Reappraisal of its putative hominine affinity reveals a closer resemblance toAustralopithecus africanus Dart, 1925. The skull, as reconstructed, is too small forH. habilis; with no indication of brain expansion overA. africanus; has a facial angle outside the hominine range, but identical with that ofA. africanus; and whose teeth are not elongated but display buccolingual expansion. Although it was found in the same strata (Member 5) as stone tools, there is no causal connection. It has been dated faunistically at 2–1.5 my BP, but due to an unconformity it is suggested that it could be older. In spite of its late date, Stw 53 shows no intermediate characters which could support a trend towardsH. habilis orA. robustus Broom, 1938. It may, therefore, represent a relict population ofA. africanus.  相似文献   

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Freshwater crayfish invasions have been studied around the world, but less so in Africa, a continent devoid of native freshwater crayfish. The present study reviews historical and current information on alien freshwater crayfish species introduced into South Africa and aims to indicate which areas are at risk from invasion. As is the case elsewhere, South Africans have shown a keen interest in both farming and keeping freshwater crayfish as pets, which has resulted in Cherax cainii, Cherax destructor, Cherax quadricarinatus and Procambarus clarkii being introduced to the country. There is evidence of successful establishment in the wild for C. quadricarinatus and P. clarkii in different parts of the country. Species distribution models suggest that the eastern part of the country and parts of the Eastern and Western Cape are at higher risk of invasion. At present, illegal translocations represent the most likely pathway of crayfish spread in South Africa. A continued risk of invasion by freshwater crayfish species in South Africa is highlighted, which reinforces the need for more research, as well as for strong mitigation measures, such as stronger policing of existing regulations, management or eradication where feasible and public education.  相似文献   

5.
Pereskia aculeata Miller (Cactaceae) is an invasive alien plant from Central and South America that has become a problematic environmental weed in South Africa. A potential biological control agent, the stem-wilter, Catorhintha schaffneri Brailovsky & Garcia (Coreidae), was collected in southern Brazil and imported into quarantine in South Africa. Field host range data suggested that C. schaffneri has a host range restricted to P. aculeata. No-choice nymph survival tests were then conducted on 27 test plant species in 9 families. Survival to the adult stage was only recorded on P. aculeata and the closely related Pereskia grandifolia Haw. (Cactaceae). Mortality was significantly higher on P. grandifolia with only 3% of the nymphs reaching the adult stage compared with 74% on P. aculeata indicating that P. aculeata is the primary host plant. P. grandifolia is native in South America and is of no agricultural importance in South Africa so any feeding on P. grandifolia in South Africa would have no negative environmental or economic consequences. In other tests, adult survival on P. aculeata [25.8 days (SE ± 3.74)] was significantly longer than on other test plant species [4.3 days (SE ± 0.36)] further confirming the host specificity of the species. Impact studies conducted in quarantine indicated that C. schaffneri is damaging to P. aculeata, significantly reducing the number of leaves and the shoot lengths of plants, even at relatively low insect densities. C. schaffneri is safe for release in South Africa and is likely to be a damaging and effective agent.  相似文献   

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Laaß, M., Hampe, O., Schudack, M., Hoff, C., Kardjilov, N. and Hilger A. (2010). New insights into the respiration and metabolic physiology of Lystrosaurus. —Acta Zoologica (Stockholm) 92 : 363–371. The first examination by neutron tomography of a skull of Lystrosaurus declivis (Therapsida, Anomodontia) from the Lower Triassic of South Africa showed complexly constructed cartilaginous maxilloturbinals in the nasal cavity. They were situated directly in the respiratory air flow and fill out most of the ventral part of the nasal chamber. Because maxilloturbinals in extant mammals and birds serve as a countercurrent exchange system for thermoregulation and humidification, their presence in the anomodont Lystrosaurus suggests strongly that Lystrosaurus was already endothermic. The endothermic metabolism allowed Lystrosaurus to tolerate high ambient temperature fluctuations. The complexly constructed maxilloturbinals could have reduced respiratory water loss because of higher ventilation rates in drought conditions in the Karoo basin.  相似文献   

7.
Rhynchosauria was an important clade of herbivorous archosauromorph reptiles during the Triassic, with a worldwide distribution. We describe a new genus and species of early rhynchosaur, E ohyosaurus wolvaardti gen. et sp. nov. , from the early Middle Triassic (early Anisian) Cynognathus Assemblage Zone (Subzone B) of the Karoo Supergroup, South Africa. Eohyosaurus wolvaardti is known from a single skull, and is recovered as the sister taxon of Rhynchosauridae in a new phylogenetic analysis. Cynognathus Subzone B has previously yielded the stratigraphically oldest well‐understood rhynchosaur species, Mesosuchus browni and Howesia browni. Eohyosaurus wolvaardti increases the rhynchosaur diversity within this stratigraphical horizon to three species. Intriguingly, all currently confirmed rhynchosaur occurrences from the Early Triassic to earliest Middle Triassic are from South Africa. This may suggest a relatively restricted palaeogeographical distribution for early rhynchosaurs, followed by a global dispersal of rhynchosaurids during the Middle Triassic. © 2015 The Linnean Society of London  相似文献   

8.
The habitat preferences of two closely related millipede species, Centrobolus richardii and C. fulgidus, were investigated on three different seral stages of a coastal dune forest successional sere north of Richards Bay, South Africa. Fixed‐width transects were used to survey millipedes in three habitats of different ages. Habitat preference occurred on both inter‐ and intra‐site levels and was influenced by season. A habitat shift was recorded for C. richardii, while C. fulgidus was dormant during the winter months, reflecting two different strategies used by these closely related species to meet their resource requirements. Successional changes previously reported are masked by these differential responses.  相似文献   

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ITS1 sequence data was obtained for fireweed (Senecio madagascariensis) andS. lautus from Australia,S. madagascariensis andS. inaequidens from South Africa andS. madagascariensis from Madagascar. Despite the low level of variation (0.0–3.4%), these data further resolve the controversy concerning the identity and origin of fireweed. They confirm that fireweed is part of the South AfricanS. madagascariensis/S. inaequidens complex, and indicate that the infestation in Australia originated from South Africa as opposed to Madagascar. This will facilitate a resumption of biological control efforts in Australia and will direct surveys for control agents to South Africa.  相似文献   

11.
The skull of a subadult female of Simopithecus darti from the “Upper Phase I” of the Makapansgat Limeworks, South Africa, is described. It is the first complete skull of Simopithecus which is recorded from the lower Pleistocene “Australopithecine cave deposits” of southern Africa. The present skull shows an interesting mixture of primitive and advanced features. In some respects, it is reminiscent of Parapapio, in others it seems to have affinities with the extant Theropithecus gelada rather than with Simopithecus oswaldi. The systematics of the fossil genus Simopithecus and of the tribe Theropithecini Jolly (1966) are discussed.  相似文献   

12.
The genus Gryllus includes 82 described species that occur in America from Canada to Argentina as well as in several areas of Africa, Europe and Asia. There are 12 species in South America, which were described in the nineteenth century based on a small number of samples and inconsistent characters such as body coloration and external morphology. The aim of this article is to redescribe Gryllus argentinus Saussure, 1874 collected in the urban areas of Pelotas, Capão do Leão and Rio Grande, in the state of Rio Grande do Sul, southern Brazil, highlighting phallic sclerites, calling song and body morphometry. We designate the lectotype male, provide a combination of diagnostic characteristics and discuss the taxonomic situation of South American Gryllus species.  相似文献   

13.
Aim Cycads constitute an ancient plant group that is generally believed to disperse poorly. However, one group of cycads (subsection Rumphiae) is thought to have dispersed relatively recently from a Malesian source area westwards to East Africa and eastwards into the Pacific, using a floatation‐facilitating layer in their seeds. We use morphological and allozyme characters to investigate the relationships among the species within this group and to deduce whether the wide distribution was achieved by recent dispersal (as evidenced by high genetic similarity) or more distant vicariance events (high genetic differentiation). Location We examined specimens collected throughout the range of subsection Rumphiae, from East Africa through Southeast Asia to Tonga in the South‐west Pacific. Methods We investigated relationships within subsection Rumphiae of the genus Cycas by analysing 18 variable (11 informative) morphological characters and 22 allozyme loci for seven of the 10 species currently assigned to this taxon. Results Distinctive morphological characters are few and fail to resolve relationships within the group. Allozyme data show that species within this subsection are closely related and suggest that there are two groups within the subsection, one comprising Cycas thouarsii (East Africa) and C. edentata (the Philippines), and the other the remaining species (from Malesia and the Pacific). The Australian species C. silvestris is sister to subsection Rumphiae in the morphological analysis but is closely allied to C. rumphii (nested within the subsection) in the allozyme analysis, suggesting that Rumphiae may be paraphyletic and that characters thought to be taxonomically important may need to be re‐evaluated. Main conclusions Cycads within subsection Rumphiae are closely related, and the wide distribution of this group was probably achieved through relatively recent oceanic dispersal events. Separate events probably account for the dispersal of these cycads into the Pacific and to Africa. The origin and distribution of C. silvestris (Australia) could be explained by a dispersal event from New Guinea or may have resulted from a former land connection between Australia and New Guinea.  相似文献   

14.
A new species of Penicillium Link ex Fries is described and illustrated. It is represented by twenty six isolates recovered from soil at twenty six different locations at the southern part of the Paul Kruger National Park in South Africa. It clearly differs from all species of the genus described so far among the Biverticillata-Symmetrica Section, and it is therefore described and proposed as a new taxon: Penicillium krugerii sp. nov.  相似文献   

15.
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   

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We investigated a variety of habitat characteristics along a land‐use gradient in an attempt to determine which factors may have influenced the population decline of redwing francolin, Francolinus levaillantii, in commercial pasture farms in the highland grasslands of Mpumalanga province, South Africa. Within three microhabitats (wetlands, rocky outcrops and grassland), number and diversity of food plants, height of the sward and percentage cover were significantly lower in habitat exposed to commercial grazing with sheep. Increased cover and height of the sward were positively correlated with higher diversity and availability of francolin food plants. Crop analyses revealed a lower intake in the number of food plant species, but higher incidence of invertebrates, ingested by birds collected in heavily grazed and frequently burned grasslands. Intestinal caecae were significantly (P < 0.001) longer in birds collected from grazed/burned grasslands – possibly associated with a low quality, more fibrous diet. Both the quantity and quality of habitat in terms of food abundance, diversity and cover are important factors influencing the distribution of redwing francolin in these grasslands.  相似文献   

18.
The fern genus Cyrtomium (Dryopteridaceae) in Africa and Madagascar is reviewed. Until now, a single Cyrtomium species ascribed to either C. caryotideum or C. micropterum (the latter often considered to be a variety of the former) was recognized for the region. This study shows that three Cyrtomium species occur in the region. One, C. falcatum, is not native to the African or Madagascan region, but has become naturalized in various parts of South Africa and Réunion. Two, formerly considered as a single taxon and confused with C. caryotideum and Indian forms thereof, are described as new – C. luctuosum from Madagascar, East, West and South Africa and C. pseudocaryotideum from South Africa. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 167 , 449–465.  相似文献   

19.
An isolated population of ~30 Capricorn Yellow Chats (Epthianura crocea macgregori) (Aves: Meliphagidae) occurs on a grassy marine plain (~4000 ha) with complex fresh to hypersaline wetlands bordering unvegetated salt flats and mangroves, the majority less than 2 m above mean sea level (MSL). While there are several species of sedge on the marine plain, only one, a tall salt‐tolerant sedge, Schoenoplectus subulatus, regularly provides tall cover and nesting habitat on the marine plain. Comparison of vegetation data between 2002 and 2018 at four breeding sites showed a loss of S. subulatus at two of the sites in conjunction with persistent extreme hypersalinity. In contrast, sites where S. subulatus recovered had elevated salinity levels coinciding with a drought in 2005–2008, but subsequently returning to pre‐drought levels. Concomitant with the loss of S. subulatus was a substantial decline in Capricorn Yellow Chat abundance. Possible drivers of persistent hypersalinity were an increase in sea level and consequent greater tidal ingress. The two most severely affected sites were relatively close to tidal influence and low points in the landscape. Evaluation of MSL data showed that habitat decline from 2002 to 2018 occurred over a period in which sea level rose by ~80 mm. While it is recognised that other variables are important, this study indicates that if sea‐level rise continues at the 2011–2017 rate of ~8.3 mm per annum, the Curtis Island marine plain will become unsuitable for Capricorn Yellow Chats in the next 60 years or less. Sixty years is likely to be a conservative estimate given that sea‐level rise rates are projected to increase further, as are the influence of more extreme weather events such as drought and storm surges on persistence of key vegetation. Ramifications for other Capricorn Yellow Chat sites and marine plain‐dependent fauna such as shorebirds also need consideration.  相似文献   

20.
Papionin monkey fossils are common in the Plio‐Pleistocene aged karst cave deposits northwest of Johannesburg in South Africa. These deposits have yielded important primate and other vertebrate fauna since their discovery in the early part of the 20th century. In this article, we describe new primate cranial and dental specimens from excavations at the site of Cooper's D in the Sterkfontein Valley that date to around 1.5 million years ago. Unlike other localities in southern Africa, most of the new fossils are referred to Theropithecus oswaldi oswaldi, an extinct gramnivorous monkey related to the living gelada. Diagnostic features of T. o. oswaldi crania and teeth include large, thickly enameled molars with tall, columnar cusps, and high molar relief, an upright mandibular ramus, postorbital constriction, and anterior fusion of temporal lines. Also present in the new sample are teeth referred to Papio sp., which show low crowned bunodont molars, and a number of indeterminate papionin teeth and skull fragments. The presence of T. o. oswaldi at Cooper's D extends the list of known localities where the taxon is found, and may indicate the presence of an open, grassland environment in the area during the early Pleistocene. The abundance of theropith fossils at Cooper's suggests that Papio was not consistently the most common papionin in southern Africa over the past three million years. Am J Phys Anthropol 151:613–629, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

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