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I. INEICH X. BONNET R. SHINE T. SHINE F. BRISCHOUX M. LEBRETON L. CHIRIO 《Biological journal of the Linnean Society. Linnean Society of London》2006,89(4):575-588
For many major phylogenetic radiations of organisms, the available ecological knowledge is disproportionately derived from a small minority of taxa, and sometimes from organisms that are highly atypical. Viperid snakes provide a good example of this situation; high-latitude cold-climate taxa in northern Europe (vipers) and North America (rattlesnakes) have been studied intensively, but more speciose radiations in tropical Africa, Asia, and Central America remain poorly known. We dissected > 500 specimens (six species) of night adders (genus Causus ), mostly from Cameroon (68%) in equatorial Africa, to quantify morphology, diets, and reproductive biology. By contrast to the 'slow' life-histories of cold-climate viperids, night adders feed frequently on frogs (rather than infrequently on mammals), and produce frequent large clutches of relatively small eggs (rather than infrequent small litters of relatively large live young). Thus, putatively 'typical' viperid attributes such as low fecundity, viviparity, and predation on mammals reflect adaptations to the invasion of cold environments by a small and perhaps atypical subset of viperid taxa. Our data on prey size suggest that one of the critical innovations of early viperids may have been an ability to subdue and ingest relatively large prey. © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 89 , 575–588. 相似文献
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SEYED MAHMOOD GHAFFARI NÚRIA GARCIA-JACAS ALFONSO SUSANNA 《Botanical journal of the Linnean Society. Linnean Society of London》2006,151(3):411-419
Chromosome counts are reported of 38 populations representing 24 species of the genus Cousinia from Iran, one of the main centres of speciation of the genus. Sixteen of the counts are new to science. Our results confirm that Cousinia exhibits a complex dysploid series ranging from x = 13 to x = 9. One of the basic chromosome numbers, x = 9, is new for the genus and must be confirmed. Some considerations on the correlation between chromosome numbers and section classification are made. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 411–419. 相似文献
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MANUEL B. CRESPO SEGUNDO RÍOS JOSÉ L. VIVERO JOSEFA PRADOS ESTEBAN HERNÁNDEZ-BERMEJO M. DOLORES LLEDÓ 《Botanical journal of the Linnean Society. Linnean Society of London》2005,149(1):121-128
Vella castrilensis sp. nov. is described from the high mountains of Granada and Jaén provinces (south-eastern Iberian Peninsula), where it grows on calcareous soils. It is a hexaploid (2 n = 68) spineless dwarf shrub, woody at the base, with oblong-lanceolate, entire to shallowly dentate leaves and fruit with an acute tongue-shaped stylar segment and strongly reticulate-nerved valves. The characteristic unique combination of vegetative, karyological and reproductive features of V. castrilensis is not present in any described taxon of the genus, and warrants recognition at the species rank. Affinities and differences with other related taxa are discussed. Phylogenetic, biogeographical, bioclimatic, ecological data and conservation proposals are also reported. © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 121–128. 相似文献
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PRADEEP K. DIVAKAR DALIP K. UPRETI 《Botanical journal of the Linnean Society. Linnean Society of London》2006,150(2):249-251
Additional occurrences of cetrarioid lichens in India are documented. Tuckneraria sikkimensis Divakar & Upreti sp. nov. is described as a new species. Tuckneraria ahtii Randlane & Saag, T. togashii (Asahina) Randlane & A. Thell and Cetrelia sinensis W.L. Culb. & C.F. Culb. are reported as new records. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 150 , 249–251. 相似文献
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PETRA DE BLOCK AARON P. DAVIS 《Botanical journal of the Linnean Society. Linnean Society of London》2006,151(3):421-424
Mantalania longipedunculata De Block & A.P. Davis, a new species of Rubiaceae (Gardenieae) from Île Sainte Marie, Madagascar, is described, illustrated, and compared with the three other species in the genus. An extinction risk assessment is given, using the categories and criteria of the World Conservation Union (IUCN). © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 421–424. 相似文献
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Association between competition and facilitation processes and vegetation spatial patterns in alpha steppes 总被引:1,自引:0,他引:1
C. L. ALADOS P. GOTOR P. BALLESTER D. NAVAS J. M. ESCOS T. NAVARRO B. CABEZUDO 《Biological journal of the Linnean Society. Linnean Society of London》2006,87(1):103-113
In semiarid ecosystems, the self-organized spatial patterns of plants associated with catastrophic shifts can emerge from a variety of processes. In this study, on moderate slopes where Stipa tenacissima cover was high, the self-organization of some of the typical species of semiarid Mediterranean matorral ( Phlomis purpurea , Sideritis oxteosylla, Helianthemum almeriense , and Brachypodium retusum ) was negatively correlated with Stipa cover. The extent of Stipa cover did not affect desert pioneer species, such as Artemisia herba-alba , Fagonia cretica , and Launaea lanifera . On pronounced slopes, the self-organizing structure of brushwood vegetation did not vary predictably with the amount of Stipa cover. We examined the competition/facilitation processes associated with self-organizing patterns in the dwarf shrub ( Phl. purpurea ) and the half shrub ( H. almeriense ). The developmental stability of H. almeriense was positively correlated with Stipa cover, which was expected because they are associated species in this seral thyme brushwood community. Indeed, facilitation processes were manifested by the developmental stability increases under the Stipa canopy, particularly on high slope areas, where Stipa is less competitive. In Phl. purpurea , negative feedback processes from competition with Stipa were manifested where Stipa cover was high and on low slopes (developmental instability increased). In general, competition with Stipa on low slopes tended to decrease plant self-organization. © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 87 , 103–113. 相似文献
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BERNHARD A. HUBER 《Zoological Journal of the Linnean Society》2003,139(4):477-527
The southern African pholcid spiders previously assigned to Pholcus and Spermophora are revised and their phylogenetic position within Pholcidae is analysed cladistically. Two distinct groups are recognized: the first is restricted to the Cape region and probably correctly placed in Spermophora ; it includes Spermophora peninsulae Lawrence and four new species. The second is more widely distributed in southern and eastern South Africa, and reaches as far north as Cameroon, Congo (Democratic Republic) and Uganda; it is assigned generic status ( Quamtana gen. nov .), and includes two species transferred from Pholcus [ Q. leptopholcica (Strand), Q. ciliata (Lawrence)] as well as 23 new species. A key to the pholcid spiders of South Africa is presented. A close correlation between a male character (distance between cheliceral apophyses) and a female character (distance between pockets on epigynum) is documented in Quamtana . © 2003 The Linnean Society of London, Zoological Journal of the Linnean Society, 2003, 139 , 477−527. 相似文献
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RUI JIANG WANG† RICHARD M. K. SAUNDERS 《Botanical journal of the Linnean Society. Linnean Society of London》2006,152(4):513-532
A revised classification of the species of Cyathocalyx (Annonaceae) occurring in western Malesia (Peninsular Malaysia, Sumatra, and Borneo) is presented, with distribution maps. Fifteen species are recognized, including two that are newly described from Borneo ( C. angustipetalus and C. magnifructus ), which are illustrated. Several important nomenclatural changes are validated, including the elevation of Drepananthus carinatus var. deltoideus to specific rank as C. deltoideus , and the transfer of the name Parartabotrys hexagynus to Cyathocalyx as C. hexagynus . Other notable nomenclatural changes include the reduction of the name C. scortechinii to synonymy with C. pubescens . © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 152 , 513–532. 相似文献
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VLADIMIR VLADIMIROV ZBIGNIEW SZELG 《Botanical journal of the Linnean Society. Linnean Society of London》2006,150(2):261-265
Hieracium petrovae Vladimirov & Szeląg sp. nov. , a new diploid (2 n = 18) species in H. sect. Pannosa Zahn, is described and illustrated from the Rhodope Mountains, South Bulgaria, and compared with related taxa. It grows in relict habitats in crevices of limestone rock together with many Balkan endemics. H. petrovae is morphologically similar to taxa from the H. pannosum , H. pilosissimum and H. heldreichii groups (collective species sensu Zahn) to some of which it is a presumed ancestral species. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 150 , 261–265. 相似文献
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RONG-JING ZHANG REN-ZHANG ZHOU FU-WU XING HONG-FENG CHEN 《Botanical journal of the Linnean Society. Linnean Society of London》2006,151(2):289-292
Magnolia polytepala Law, R.Z. Zhou & R.J. Zhang sp. nov. (Magnoliaceae) a new species from Fujian, south-east China, is described and illustrated. The species was found growing only in the evergreen broad-leaved forests of Mount Wuyishan at altitudes of 500–1200 m. Notes are also presented on the phenology and conservation status of the new species. It is closely related to Magnolia liliiflora Desr., but differs from the latter in its stunted habit (less than 2 m tall) and tepals, which are more numerous (12–16) and not contorted at the base. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 289–292. 相似文献
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ANTON HOFREITER OLE B. LYSHEDE 《Botanical journal of the Linnean Society. Linnean Society of London》2006,152(1):73-90
The leaf anatomy of Bomarea is described and related to ecological conditions. The principal architecture of all species is very similar; adaptations are developed in numerous differences, for instance degree of lignification. All species have inverse leaves, the adaxial side being the stomatous side. In most species, the leaves are resupinate, the lower surface being the adaxial. Theories for the cause of resupination are discussed. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 152 , 73–90. 相似文献
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QIONG YUAN QIN-ER YANG 《Botanical journal of the Linnean Society. Linnean Society of London》2006,150(3):343-353
Chromosome numbers and morphology in 22 populations belonging to 11 taxa of Aconitum subgenus Lycoctonum (Ranunculaceae) from China were studied. Some taxa were diploid, with 2 n = 16, but four species and two varieties were found to be tetraploid, with 2 n = 32. They are concentrated in the Hengduan Mountains region in south-west China, indicating that polyploidy could have played an important role in the speciation of the subgenus in this region, one of the areas of the world with a high concentration of endemic species. The relationships of some of the species are discussed. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 150 , 343–353. 相似文献
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SÒNIA GARCIA TERESA GARNATJE SHAGDAR DARIIMAA SHAGDAR TSOOJ JOAN VALLÈS 《Botanical journal of the Linnean Society. Linnean Society of London》2006,150(2):203-210
This study encompasses 25 chromosome counts of 18 species in the subtribe Artemisiinae (tribe Anthemideae) of the family Asteraceae, from Mongolia. Most (15 species) belong to Artemisia , the largest genus of the subtribe, whereas the others come from two genera very closely related to it: Ajania (two species) and Neopallasia (one species). Eleven counts are new reports, three are not consistent with previous reports and the remainder confirm scanty earlier information. The majority of the species have x = 9 as their basic chromosome number, but there are some taxa with x = 8. Ploidy levels range from 2 x to 6 x . The presence of B-chromosomes was detected in Ajania fruticulosa . © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 150 , 203–210. 相似文献
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A mass return to land of the megalop of the land crab Gecarcinus ruricola is reported. The return occurred in June 2004 on the island of Providencia in the western Caribbean: this is the first detailed report of larval return in this species, and the most detailed report for any gecarcinid. Crabs emerged from the sea as megalops over 2 to 3 days, and moved rapidly landwards. Vast numbers migrated > 50 m across land before moulting to the first crab – the megalop is clearly the invasive stage. The megalop is described for the first time, and criteria are identified to discriminate it from other Caribbean gecarcinids. © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 146 , 149–164. 相似文献