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1.
Silene doganii A.Duran & Y.Menemen sp. nov. from the Amanos Mountains (C6: Osmaniye-Turkey) is described and illustrated. It is closely related to S. caramanica Boiss. & Heldr., from which it differs mainly in its habit, hairiness, leaf and floral features.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 109−113.  相似文献   

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The evolution of venom-delivery systems in snakes   总被引:3,自引:0,他引:3  
The Colubroidea represents approximately 2300 of the 2700 species of living snakes and includes all venomous taxa. Although many morphological studies of colubroid snakes have been carried over the last hundred years, the phylogenetic relationships within this group are poorly known. In this study, components of the venom-delivery system (VDS) were examined within the context of two conflicting phylogenetic hypotheses proposed in 1988 by Cadle and in 1998 by Kraus & Braun. The results suggest that several major morphological changes occurred early in colubroid evolution: a Duvernoy's gland evolved, the posterior maxillary teeth became specialized relative to the anterior maxillary teeth, and the attachment of the pterygoideus muscle moved forward to a position associated with the posterior maxillary teeth. These innovations may have allowed the great radiation of colubroid snakes that led to the Colubroidea representing such a large percentage of living snakes. More recently, three separate lineages of colubroids have independently evolved highly specialized front-fanged VDSs with large and complex venom glands, venom gland compressor muscles, and tubular fangs.  © 2003 The Linnean Society of London, Zoological Journal of the Linnean Society, 2003, 137 , 337−354.  相似文献   

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Hieracium kittanae Vladimirov, a new diploid (2 n  = 18) species restricted to a few gorges in the Central Rhodope Mountains, south Bulgaria, is described and illustrated. It occurs in crevices of limestone rock in shady to sunny places with high atmospheric humidity. Morphologically, it to some extent resembles taxa from the H. glaucinum and H. schmidtii groups, but is otherwise very distinct, without close relatives in the Rhodope and neighbouring mountains.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003 , 143 , 213−218.  相似文献   

6.
Preliminary checklist of the orchids of Chile   总被引:1,自引:0,他引:1  
This article provides a preliminary checklist of the orchids occurring in Chile, based on historical and recently published literature. Data compilation was assisted by using databases available on the Web (IPNI, W3Tropicos and KR). The list comprises seven genera ( Aa , Bipinnula , Brachystele , Chloraea , Codonorchis , Gavilea and Habenaria ) and 50 taxa (49 species and one variety), 25 of which are believed to be endemic to Chile. It includes the publication of a new combination, Gavilea feuilleana comb. nov.   © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 449−451.  相似文献   

7.
The species of Goniothalamus (Annonaceae) occurring in Peninsular Malaysia and Singapore are revised, updating the previous taxonomic treatment by James Sinclair, published in 1955. A total of 18 species is recognized, including a new species, G. tomentosus . Collections referrable to G. tomentosus were previously determined as ' G. marcanii '; examination of the types of G. marcanii reveals that the two taxa are not conspecific, however, and a new name is accordingly validated here. Goniothalamus tomentosus has closest affinities with the Javan/Sumatran species G. costulatus . Other important nomenclatural changes include the reduction of G. umbrosus to synonymy with G. tapis .  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003, 142 , 321−339.  相似文献   

8.
Karyology of some Brazilian species of Alismataceae   总被引:1,自引:0,他引:1  
The family Alismataceae ( sensu Cronquist) comprises 11 genera and 75 species of aquatic and semiaquatic herbs. In Brazil, only the two most speciose genera, Echinodorus Rich. ex Engelm. and Sagittaria L., are present. The chromosome number 2 n  = 22 is common to all species. We present karyotypes for eight species, together with their asymmetry index (TF%) and total chromatin length (TCL). All karyotypes have high karyotypic asymmetry and TCL, due to their large and mostly acrocentric chromosomes. The chromosomal evolution of the Alismatidae group is discussed.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 159−164.  相似文献   

9.
Two new species of the genus Galium are described from the Iberian Peninsula: G. moralesianum Ortega-Olivencia & Devesa, and G. talaveranum Ortega-Olivencia & Devesa. The first grows on limestone or dolomitic-limestone outcrops in south-east Spain (the Segura and Gádor mountain ranges) and shows morphological similarities with G. boissieranum Ehrend. & Krendl, which is endemic to southern Spain (mountains of Málaga). The second inhabits the margins of water courses, alder stands and cork-oak dehesas (parkland-type systems) of the west of the Iberian Peninsula, and is morphologically reminiscent of G. mollugo L. The chromosome numbers of these two species and of G. boissieranum are given.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 177−187.  相似文献   

10.
Riccia fruticulosa O.F.Müll., 1782 from Norway is a valid name, referring to Riccardia palmata (Hedw.) Carruth. In 1785 Dickson misidentified British plants of a blue Metzgeria as R. fruticulosa . The European blue species of Metzgeria is conspecific with M. violacea (Ach.) Dumort., which replaces M. fruticulosa auct. The true origin of the type of Jungermannia violacea Ach., 1805 is probably Tierra del Fuego (rather than Dusky Bay, New Zealand), where the species is widespread. Reports from Australasia, Asia and Africa are all erroneous. The blue colour of Jungermanniales is found only in living plants and is derived from the oil-bodies. In contrast, that of Metzgeria appears only after death; its biological function is unknown.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003, 142 , 229−235.  相似文献   

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Because of the poor state of knowledge of many of the gymnophthalmid genera, systematic revision is necessary to render the classification consistent with evolutionary history. To that end, I conducted a review of the species of three genera of the Cercosaurinae which appear to form a monophyletic group: Cercosaura , Pantodactylus , and Prionodactylus . Phylogenetic analysis of 61 morphological characters was conducted after specimens of all species were examined to evaluate the composition of each taxon. The phylogenetic reconstruction suggested that the genus Prionodactylus was paraphyletic. A new phylogenetic classification is proposed that synonymizes Pantodactylus and Prionodactylus with Cercosaura. Cercosaura is redefined to include 11 species and seven subspecies. A key is provided to distinguish among species.  © 2003 The Linnean Society of London, Zoological Journal of the Linnean Society, 2003, 137 , 101−115.  相似文献   

13.
This study investigated the ecomorphology of pharyngeal jaw structure and durophagy in three families of marine teleosts: the Sciaenidae, Haemulidae and Carangidae. Regressions of the bone and muscle mass of pharyngeal jaws were generated to elucidate the differences associated with eating hard-bodied and soft-bodied prey; within-family comparisons revealed significant differences in masses of bones and muscles involved with processing the former. Generally, the durophagous species − Trachinotus carolinus (Carangidae), Pogonias cromis (Sciaenidae) and Anisotremus surinamensis (Haemulidae) − had heavier and stronger pharyngeal toothplates and larger protractor pectoralis muscles, with masses of these musculoskeletal elements ranging from five times to nearly an order of magnitude larger than those of their soft-prey feeding relatives. Pogonias cromis and T. carolinus demonstrate convergence in the ontogeny and morphological modification of the pharyngeal toothplates and protractor pectoralis muscles that enhance crushing ability. In the Haemulidae, moderate size increases in a few pharyngeal jaw elements (and larger overall body size in A. surinamensis ) are sufficient for durophagy. Morphospace analysis of six species from the three families illustrates the strong functional association between the biomechanical properties of prey and the relative sizes of biting and transport mechanisms.  © 2003 The Linnean Society of London, Biological Journal of the Linnean Society, 2003, 80 , 147−165.  相似文献   

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The higher-level relationships of anurans have been explored by numerous studies, producing a variety of hypotheses. The relationships of the basal anurans ('archaeobatrachians') are, however, poorly known . In part, this may be because the adult morphology of basal anurans is derived and therefore may not provide suitable phylogenetic signal. Recently, several authors have shown the phylogenetic utility of information derived from anuran larvae. In this paper we conduct separate and combined analyses of anuran relationships based on adult and larval morphology. Our combined results suggest that anurans form two major clades − the pipoids and all other frogs. Evidence also suggests that, taken together, Neobatrachia and Pelobatoidea form a monophyletic group. We discuss support for various groupings as shown by the different data sets. We also comment on the consequences of our phylogenetic hypothesis for the interpretation of reduction of vertebral elements and evolution of Orton's tadpole types in anurans.  © 2003 The Linnean Society of London, Zoological Journal of the Linnean Society, 2003, 139 , 129−155.  相似文献   

16.
A morphological study, both in the field and from herbarium material, showed that there are no convincing characteristics separating the Turkish endemics Iris stenophylla ssp. stenophylla and ssp. allisonii . A cytological survey revealed chromosome numbers of 2 n  = 24, 26 and 26 + 1B. No variation in either chromosome number or karyotype was found in ssp. allisonii , which always had 2 n  = 26, although the chromosome number and karyotypes of ssp. stenophylla were variable. Since neither morphological nor cytological differences were sufficient to separate the two subspecies, I. stenophylla ssp. allisonii is therefore reduced to a synonym of I. stenophylla .  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 115−127.  相似文献   

17.
The Cainotheriidae are small artiodactyls that suddenly appeared in the late Eocene of western Europe. A revision of early Oligocene cainotheriid lineages is proposed on the basis of newly dated material from the Quercy Phosphorites (south-western France). A significant diversification of the group occurred at the end of the Eocene. Few species seem to have persisted through the Eocene/Oligocene boundary, but the Cainotheriidae subsequently diversified rapidly during the early Oligocene.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 144 , 145−166.  相似文献   

18.
In order to investigate continental-scale patterns of plant species richness and rarity, distribution maps of 3661 plant species were digitized into a one degree grid of sub-Saharan Africa using the WORLDMAP computer programme. Cells with high species richness were also likely to be those containing the greatest number of species of restricted range, but areas such as the South African Cape and the Eastern Arc mountains were found to have more restricted-range species than predicted from their richness scores. The two environmental predictors which had the strongest individual relationships with both species richness and range-size rarity were absolute maximum annual temperature and mean monthly potential evapotranspiration. However, correlative predictive powers of these variables were low, with R =−0.58 and R =−0.54, respectively ( P  < 0.01). Multiple regression also failed to produce a strong explanatory model for observed continental-scale patterns of diversity. Spatial variability analysis showed that this was likely to be because different environmental parameters predicted different centres of richness and rarity. West African species richness was better predicted by absolute maximum annual temperature, whereas East African species richness was better predicted by mean monthly potential evapotranspiration.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 142 , 187–197.  相似文献   

19.
Three Asian species of the genus Hediste (Nereididae, Polychaeta, Annelida), including two new species, are reviewed. Hediste japonica (Izuka, 1908) was redescribed based on recently discovered type material and on additional specimens newly collected from the Ariake Sea in Japan and the west coast of Korea. Two new species, H .  diadroma and H. atoka , were described based on specimens collected from Japan. These three species are morphologically similar, but distinguishable by some differences in parapodial and chaetal morphology, at least at the sexually mature stage. The presence of homogomph falcigers and the absence of heterogomph spinigers are unique characteristics of H. japonica among this genus. Inconspicuous epitokous metamorphosis occurred as a slight enlargement of the eyes and parapodial ligules in mature adults of H. diadroma sp. nov. and H. japonica in combination with their reproductive swarming and pelagic larval development. The epitoke-specific sesquigomph spinigers were added in mature adults of H. diadroma sp. nov., while the number of ordinary homogomph spinigers increased in some adults of H. japonica. Epitokous metamorphosis in the Hediste species was compared with that in other nereidid genera. No epitokous metamorphosis was observed in H. atoka sp. nov., corresponding to its reproduction without swarming and to its development without a planktonic larval stage. Significant differences in paragnath numbers in the maxillary ring of the proboscis were found among the three species, suggesting different feeding habits. In Japan, the present distribution of H. japonica is restricted to muddy tidal flats in the inner part of the Ariake Sea, probably due to recent human impact, while the other two species are widespread.  © 2003 The Linnean Society of London. Zoological Journal of the Linnean Society, 2003, 137, 403−445  相似文献   

20.
The extent of chromosome structural differences such as permanent translocations and paracentric inversions has been studied in the hybrid complex of Phlomis composita and its putative parental taxa P. lychnitis and P. crinita . They are detected as meiotic abnormalities during microsporogenesis. In total, 117 plants from 19 populations in Andalusia (southern Spain) and Levante (eastern Spain) were studied for ploidy level, chromosome clumping, multivalent or univalent formation, late bivalent disjunction with bridges, chromatin bridges and fragments, irregular polysporads and variable pollen size. All individuals had the diploid chromosome number 2 n  = 20, with no significant difference in the frequencies of the above meiotic abnormalities either at taxon or population levels. However, very different frequencies were observed on the regional scale between populations in Andalusia and Levante. The results are discussed within the theoretical framework of homoploid hybrid or recombinational speciation.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 79−85.  相似文献   

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