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1.
Barred Long‐tailed Cuckoo (Cercococcyx montanus) currently comprises two morphologically distinct subspecies, one resident in the Albertine Rift (montanus) and one in east and southeast Africa (patulus) in which there are migrations that are poorly understood. Based on nuclear and mitochondrial DNA sequences, we find that two specimens collected in relatively low‐elevation forest in the Albertine Rift were correctly identified from plumage as the migratory subspecies whose closest known breeding area is > 800 km to the east. We discuss ways in which this unique migratory pattern could have evolved and argue that migration was gained and then lost in the C. montanus complex. Based on consistent morphological and genetic differences, we suggest that Barred Long‐tailed Cuckoo is best treated as two species, one of which (C. montanus) is a non‐migratory Albertine Rift endemic. 相似文献
2.
JOÃO A. N. BATISTA THIAGO E. C. MENEGUZZO GERARDO A. SALAZAR ALINE J. RAMALHO LUCIANO DE BEM BIANCHETTI 《Botanical journal of the Linnean Society. Linnean Society of London》2011,165(4):348-363
Nothostele is a rare genus endemic to central Brazil. The taxonomy of the genus is controversial and almost every taxonomist has had a different point of view regarding its generic and subtribal classification. After the first collection 138 years ago, N. acianthiformis has been collected again and we report here a phylogenetic analysis of the genus based on nuclear ribosomal internal transcribed spacer and plastid matK and trnL–trnF sequence data. Our results show that Nothostele belongs to subtribe Spiranthinae and is sister to Eltroplectris within the Stenorrhynchos clade. A reanalysis of gynostemium morphology shows that the presence of a hamulus was misinterpreted in Nothostele and that the placement of the genus in Cranichidinae based on morphology of the pollinarium is unwarranted. Furthermore, the flattened, sessile, prostrate leaves of N. acianthiformis, which are described here for the first time, occur in some Spiranthinae but are atypical in Cranichidinae. Specimens from Brasília in the Brazilian central plateau are a distinct new species, which is described here as N. brasiliaënsis. Currently, the genus comprises two disjunct species restricted to the cerrado and rocky field vegetation of central Brazil. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 165 , 348–363. 相似文献
3.
A vast radiation of hydrobiid spring snails endemic to New Caledonia, a continental island in the Southwest Pacific known for its unique flora and fauna, is described. This radiation comprises a total of 54 named species of which 50 are new. The majority of the species belong to the most basal genus, Hemistomia, which happens to be the first one described from New Caledonia. The remaining species are attributed to four genera, Kanakyella, Pidaconomus, Caledoconcha, and Leiorhagium, which are all introduced in this paper. The radiation as a whole is characterized by the formation of the digestive gland, the stomach with an additional, ciliated proximal chamber, and the subdivision of the pallial oviduct. Whether or not a denticle situated behind the outer lip is a synapomorphy of the whole group cannot be stated with certainty. The genera are distinguished mainly by features of the genital system. For the cladistic analysis, which resulted in 419 equally parsimonious trees, only five characters could be used, and even those were not free of homoplasy. The genera Hemistomia and Pidaconomus are paraphyletic according to this analysis. In contrast to the widely accepted principles of phylogenetic systematics we retain these paraphyletic genera, because otherwise the diversification, i.e. the evolution, which has taken place within the clade could not be expressed in the classification. The majority of the species occur in very restricted areas. Twenty-six (48%) species were found in a single locality and only six species (11%) in ten or more places. The hydrobiid diversity of west coast drainages is much higher than that of river systems draining to the east. This is, at least partly, explained by the differing precipitation regimes and geological conditions of the regions considered. The west coast receives much less rainfall so that in continuous periods of drought the area of a species would be fragmented by drying up of springs and consequently gene flow between the remaining populations reduced, enhancing speciation. In addition, the west is geologically more heterogenous. Unfavourable, insular ultramafic mountains represent barriers for the dispersal along the west coast. Many of the taxa are highly threatened to become extinct in the closer future as a consequence of human activities, such as deforestation, agriculture, surface mining, or uncontrolled fires. The conservation of the unique New Caledonian radiation of crenobiontic gastropods requires a transformation of land management practices on privately-owned sites, and a more global reappraisal of the impact of fire and deforestation on water resources. This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
4.
Anne Laudisoit Pierre Huyghe Jacob Willie Bienvenu Ndjoku Tiffany Scholier Jérôme Dz'na Nikki Tagg Samantha Maher Claude Mande Tara Hoda Thurston Cleveland Hicks Pascal Baelo Oti Kpanyogo Gustave Ndjango Ngbathe Guy Crispin Gembu Joseph Omatoko Justin Asimonyio Anio Herwig Leirs Erik Verheyen 《Conservation Science and Practice》2021,3(6):e403
This paper documents a community of eastern chimpanzees (Pan troglodytes schweinfurthii Giglioli, 1872) inhabiting three relict forest fragments situated on the Lake Albert escarpment, down the Ituri highlands, of eastern Democratic Republic of the Congo (DRC). The area explored had a combined forested surface of ±18.15 km2 in 2017, shrinking by 1.2% per year between 2010 and 2015. Between 2015 and 2017, we found 160 chimpanzee nests along 37.6 km of pilot walks, some up to 2,000 m altitude. Another 123 nests logged along 6.7 km transects led to an estimate of chimpanzee density of 4.62 weaned individuals per square kilometer of forest habitat. Camera-trap images and direct observations revealed that this community is comprised of a minimum of 42 weaned individuals, which translates into an estimated density of 2.3 chimpanzees per square kilometer. The increasing rate of forest degradation threatens to erode the cultural and genetic diversity of nonhuman primates in eastern DRC; the local people however exhibit willingness to establish a community managed reserve. We hope that this report will lead to the recognition of this site as a Chimpanzee Conservation Unit, facilitating further research in these “Relict Altitude Forests Fragments of the Albert Lake Escarpment” (or RAFALE landscape) and the Ituri highlands where other undocumented chimpanzee communities occur. 相似文献
5.
Montague H. C. Neate-Clegg Timothy G. O'Brien Felix Mulindahabi Çağan Hakkı Şekercioğlu 《Conservation Science and Practice》2020,2(11):e291
Climate change threatens to push species to higher elevations and eventual extinction. Birds, in particular, are shown to be shifting upslope in the Neotropics and Southeast Asia. Yet previous studies have lacked the temporal resolution to investigate distributional dynamics over time in relation to climatic fluctuations, especially in the understudied Afrotropics. Here, we used 15 years of point-count data from across an elevational gradient (1,767–2,940 m) in Rwanda, to assess elevational shift rates and dynamics in a community of Afrotropical birds. In general, species shifted their elevations upslope by 1.9 m/year, especially at their lower elevational limits which shifted by 4.4 m/year. Importantly, these shifts occurred despite the fact that local temperature and precipitation showed little trend over the study period. Moreover, the interannual distributions of few species were associated with temperature, suggesting that temperature played little direct role in determining elevational distributions of birds. Instead, upslope shifts may be more related to incremental shifts in habitat and resources which lag behind decades of increased temperature in the region. Precipitation appeared to have more of an effect than temperature in determining interannual elevational changes, allowing species to expand their ranges in years of higher rainfall. Our results highlight the need to understand the mechanisms driving upslope shifts as they occur throughout the tropics. It will be critical for montane regions of the tropics to preserve contiguous blocks of forest across elevational gradients to allow wildlife to shift unimpeded. 相似文献
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7.
The major aim of this study was to compare the phylogeographic patterns of codistributed rodents from the fragmented montane rainforests of the Albertine Rift region of east central Africa. We sampled individuals of three endemic rodent species, Hylomyscus denniae, Hybomys lunaris and Lophuromys woosnami from four localities in the Albertine Rift. We analysed mitochondrial DNA sequence variation from fragments of the cytochrome b and control region genes and found significant phylogeographic structuring for the three taxa examined. The recovered phylogenies suggest that climatic fluctuations and volcanic activity of the Virunga Volcanoes chain have caused the fragmentation of rainforest habitat during the past 2 million years. This fragmentation has played a major role in the diversification of the montane endemic rodents of the region. Estimation of the divergence times within each species suggests a separation of the major clades occurring during the mid to late Pleistocene. 相似文献
8.
We illustrate the use of Faith's 'Phylogenetic Diversity' measure to compare the phylogeographic structure of two bird species with patterns of avian endemism across six mountains in Cameroon and Equatorial Guinea. The Mountain Greenbul and Cameroon Blue-headed Sunbird showed phylogeographic patterns that together defined three biogeographic regions: Bioko, Mt. Cameroon, and the northern mountains of Cameroon. In contrast, the distributions of endemic species were largely a function of geographical distance, with close mountains sharing more endemic species than distant mountains. Moreover, for both species, populations on Mt. Cameroon were distinctive with respect to the ecologically relevant character bill size. Our results, while preliminary, illustrate the utility of a comparative approach for identifying geographical regions that harbour evolutionarily distinct populations and caution against using only the distributional patterns of endemics to prioritize regions for conservation. Results show that patterns of endemism may not be concordant with patterns of phylogenetic diversity nor morphological variation in a character important in fitness. While incorporation of additional species from unrelated taxa will be necessary to draw definitive conclusions about evolutionarily distinct regions, our preliminary results suggest a conservation approach for the Afromontane region of the Gulf of Guinea that would: (i) emphasize protection of both Bioko and Mt. Cameroon, thereby maximizing preservation of within-species phylogenetic and morphologic diversity; (ii) emphasize protection within the northern mountains to further conserve intraspecific phylogenetic diversity and maximize protection of endemic species. 相似文献
9.
JULIANA DE PAULA-SOUZA VINICIUS CASTRO SOUZA 《Botanical journal of the Linnean Society. Linnean Society of London》2003,141(4):503-506
A new species of Hybanthus (Violaceae) from north-eastern Brazil is described and illustrated. Hybanthus verrucosus Paula-Souza is endemic to 'caatingas' of Bahia and Alagoas states and is very distinct from all other Brazilian species of the genus, for its anterior petal, which is covered with small wart-like outgrowths. Other distinctive characteristics of the new species and its relationship with a closely related species ( H. atropurpureus (A.St.-Hil.) Taub.) are discussed. © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 141 , 503–506. 相似文献
10.
Perrins CM 《Trends in ecology & evolution》1998,13(12):517-518
Endemic Bird Areas of the World. Priorities for Biodiversity Conservation by A.J. Stattersfield, M.J. Crosby, A.J. Long and D.C. Wege, Birdlife International, 1997. £37.00 pbk (860 pages) ISBN 0946 888 33 7CDROM: Birds of the World—A Multimedia Encyclopedia, Ransom, 1997. £14.99 ISBN 1 863 89 1748 相似文献
11.
Luany L. Campos Louise C. Gomes Camila Gentilin-Avanci Evanilde Benedito 《Zeitschrift fur angewandte Ichthyologie》2020,36(6):866-869
This study reports the Length-Weight Relationships (LWR) for 10 freshwater fish species sampled in the Atlantic Rainforest, Southern Brazil. Sampling was conducted between 2016 and 2017, in nine streams, using electrofishing. Collected fishes were fixed in formalin, and thus some shrinking was unavoidable. The values of parameter b of the LWR (W = aLb) ranged between 2.5 and 3.5. We report for the first time the LWR for seven species: Geophagus iporanguensis, Isbrueckerichthys duseni, Hypostomus interruptus, Kronichthys lacerta, Chasmocranu lopezi, Astyanax lacustris e Neoplecostomus ribeirensis. We highlight the importance of the LWR data in supporting further studies on fish stocks and environment in the Atlantic Rainforest, thereby contributing to the database needed to develop fisheries management and maintenance of ecosystem services. 相似文献
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Denis Copila&#x;‐Ciocianu Alina‐Andreea Zim a Adam Petrusek 《Journal of Zoological Systematics and Evolutionary Research》2019,57(2):272-297
The multidisciplinarity of integrative taxonomy is particularly useful for clarifying the systematics of speciose groups that are poorly differentiated morphologically, and this approach can also illuminate their evolutionary history and biogeography. Here, we utilize it to examine the systematics and taxonomy of a newly recognized amphipod species, Gammarus hamaticornis n. sp., which belongs to a highly diverse genus of endemic freshwater crustaceans that show very limited morphological differentiation. Since this species is endemic to northern Dobrogea, a region at the northwestern Black Sea coast devoid of permafrost during the Last Glacial Maximum, we hypothesized that it survived in situ during the Quaternary climatic oscillations. We first examined the phylogenetic position of Gammarus hamaticornis n. sp. within the genus and then compared its morphology, phylogeography, distribution, and climatic niche with that of its sister species. Results indicate that G. hamaticornis n. sp. is most closely related to its widely distributed northern neighbor, G. kischineffensis, and a remarkable agreement was observed among morphological, multilocus coalescent and climatic analyses which supported the distinctiveness of both taxa. These apparently diverged during the Pliocene from a common ancestor that likely colonized freshwaters from the adjacent brackish basins of the shrinking Paratethys. The results indicate that G. hamaticornis n. sp. has persisted throughout the Pleistocene in northern Dobrogea, a hitherto hypothesized refugium confirmed for the first time with molecular genetic data. Due to its narrow geographical range, rarity in the local communities and highly fluctuating nature of the streams it inhabits, this species should be in the focus of future conservation priorities. 相似文献
14.
Aim The genus Kniphofia contains 71 species with an African–Malagasy distribution, including one species from Yemen. The genus has a general Afromontane distribution. Here we explore whether Kniphofia is a floristic indicator of the Afromontane centre of endemism and diversity. The South Africa Centre of diversity and endemism was explored in greater detail to understand biogeographical patterns. Location Africa, Afromontane Region, southern Africa, Madagascar and Yemen. Methods Diversity and endemism for the genus were examined at the continental scale using a chorological approach. Biogeographical patterns and endemism in the South Africa Centre were examined in greater detail using chorology, phenetics, parsimony analysis of endemicity (PAE) and mapping of range‐restricted taxa. Results Six centres of diversity were recovered, five of which are also centres of endemism. Eight subcentres of diversity are proposed, of which only two are considered subcentres of endemism. The South Africa Centre is the most species‐rich region and the largest centre of endemism for Kniphofia. The phenetic analysis of the South Africa Centre at the full degree square scale recovered three biogeographical areas that correspond with the subcentres obtained from the chorological analysis. The PAE (at the full degree square scale) and the mapping of range‐restricted taxa recovered two and six areas of endemism (AOEs), respectively. These latter two approaches produced results of limited value, possibly as a result of inadequate collecting of Kniphofia species. Only two AOEs were identified by PAE and these are embedded within two of the six AOEs recovered by the mapping of range‐restricted taxa. All the above AOEs are within the three subcentres found by chorological and phenetic analysis (at the full degree square scale) for the South Africa Centre. Main conclusions The centres for Kniphofia broadly correspond to the Afromontane regional mountain systems, but with some notable differences. We regard Kniphofia as a floristic indicator of the Afromontane Region sensu lato. In southern Africa, the phenetic approach at the full‐degree scale retrieved areas that correlate well with those obtained by the chorological approach. 相似文献
15.
Stefan Abrahamczyk Michaela Jandov Zuzana Líblov Steven B. Janssens Tom&#x; Dostlek Norbert Holstein Eberhard Fischer 《Ecology and evolution》2021,11(23):17485
In the species‐rich genus Impatiens, few natural hybrids are known, even though closely related species often occur sympatrically. In this study, we aim to bridge the gap between micro‐ and macro‐evolution to disentangle pre‐ and postzygotic mechanisms that may prevent hybridization in the Impatiens purpureoviolacea complex from Central Africa. We analyzed habitat types, species distribution, pollination syndromes, pollinator dependency, genome sizes, and chromosome numbers of seven out of the ten species of the complex as well as of one natural hybrid and reconstructed the ancestral chromosome numbers of the complex. Several species of the complex occur in sympatry or geographically very close to each other. All of them are characterized by pre‐ and/or postzygotic mechanisms potentially preventing hybridization. We found four independent polyploidization events within the complex. The only known natural hybrid always appears as single individual and is self‐fertile. But the plants resulting from self‐pollinated seeds often die shortly after first flowering. These results indicate that the investigated mechanisms in combination may effectively but not absolutely prevent hybridization in Impatiens and probably occur in other genera with sympatric species as well. 相似文献
16.
MAX DEBUSSCHE JOHN D. THOMPSON 《Botanical journal of the Linnean Society. Linnean Society of London》2002,139(2):133-144
In Cyclamen subgenus Psilanthum , previous authors have recognized three species ( C. repandum, C. balearicum and C. creticum ), with C. repandum subdivided into three subspecies (ssp. repandum , ssp. peloponnesiacum and ssp. rhodense ), and two varieties (var. vividum and var. peloponnesiacum ) within C. repandum ssp. peloponnesiacum . To examine the validity of this classification and the degree of morphological differentiation among closely related endemic taxa with disjunct distributions, we undertook analyses of three quantitative and eight qualitative morphological traits of flowers and leaves, most of which have previously been used without statistical comparison in the classification of the different taxa. Cyclamen balearicum showed high levels of morphological differentiation from all other taxa in subgenus Psilanthum consistent with its specific status. In contrast, morphological differentiation between C. creticum and subspecies of C. repandum was similar to that among the three subspecies of C. repandum . When compared with a recent molecular phylogeny of this subgenus, our results suggest that C. creticum may best be described as a geographical subspecies of C. repandum . The two varieties of C. repandum ssp. peloponnesiacum showed few significant differences for individual traits and their overall morphology is very similar to each other. The morphology of plants at three sites on Corsica strongly suggest, consistent with molecular data, the occurrence of hybrid populations between C. balearicum (outside of its previously recognized distribution) and local C. repandum . © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 139 , 133–144. 相似文献
17.
AL&#;A. DÖNMEZ B&#;ROL MUTLU 《Botanical journal of the Linnean Society. Linnean Society of London》2004,146(2):251-255
Nigella turcica a new species endemic to north-eastern Turkey is described and illustrated. Morphological differences between the species and the closely related species, N. sativa , are discussed and the IUCN threatened category is proposed. A distribution map of the new species and its related taxon is given. © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 251–255. 相似文献
18.
MARTIN IRESTEDT MAGNUS GELANG GEORGE SANGSTER URBAN OLSSON PER G. P. ERICSON PER ALSTRÖM 《Ibis》2011,153(1):78-86
We present molecular evidence that Neumann’s Warbler Hemitesia neumanni is deeply nested within the Cettiidae. The species’ distribution in the Albertine Rift of East Africa is intriguing, as the family Cettiidae is principally an Asian radiation. This disjunct distribution could be a result of colonization of Africa by long‐distance dispersal, or the Cettiidae may at some point in the past have had a much larger geographical distribution that also covered parts of Africa. 相似文献
19.
DAVID H. LORENCE WARREN L. WAGNER ARNAUD MOULY JACQUES FLORENCE 《Botanical journal of the Linnean Society. Linnean Society of London》2007,155(4):581-597
During the preparation of the Vascular Flora of the Marquesas Islands and Flore de la Polynésie française , four new species of Ixora L. (Rubiaceae) have come to light and are described and illustrated herein: Ixora jourdanii Mouly & J.Florence, Ixora tahuataensis Mouly & J.Florence, Ixora uahukaensis Lorence & W.L.Wagner, and Ixora uapouensis Lorence & W.L.Wagner. In addition to these new taxa, the following three species of Ixora previously described from the Marquesas are recognized: Ixora marquesensis F.Br., Ixora ooumuensis J.Florence, and Ixora spathoidea F.Br. As the Marquesan environment is under serious threat from human impact, feral animals and weeds, the conservation status was estimated for each Ixora species. It is concluded that all Marquesan taxa are in need of inclusion in the IUCN Red List, their status ranging from endangered to critically endangered. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 581–597. 相似文献
20.
XIANG QIAOPING A. FAJONFLS LI ZHENYU FU LIKUO LIU ZHENGYU 《Botanical journal of the Linnean Society. Linnean Society of London》2002,139(3):305-310
After more than a century, the only conifer species listed as being extinct in the wild (EW) by IUCN-SSC has been rediscovered in the Dabashan Mountains of central China. The history, taxonomy, ecology and conservation of Thuja sutchuenensis are described, and illustrations, based on both the earliest and latest collection of botanical material of this tree, are provided. The taxonomic context of this rare species is discussed. © 2002 The Linnean Society of London , Botanical Journal of the Linnean Society , 2002, 139 , 305–310. 相似文献