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The majority of authors consider Festuca jubata Lowe as an endemic species common to Madeira and the Azores. Saint-Yves proposed that F. jubata was an Azorean endemic and described a geovicarious taxon in Madeira: F. filiformis C. Sm. ex Link in Buch ssp. mandonii St.-Yves. We undertook a complete bibliographical revision of the taxonomy, nomenclature, and chorology of F. jubata s.l. , and contrasted it with morphological and anatomical studies performed on samples from the Azores and Madeira. Azorean plants usually identified as F. jubata had a character combination distinct from that of those with a Madeiran provenance. Saint-Yves' proposal of two independent taxa was correct, but he erroneously considered F. jubata as an Azorean endemic because the name F. jubata was based on Madeiran plants. Consequently, F. jubata auct. pl. from the Azores belongs to a new species.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 493–499.  相似文献   
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A new species of the section Spartopsis Dumort. of the genus Cytisus Desf. (Fabaceae) is described. The new species, Cytisus insularis , is restricted to the western islands of Galicia (north-west Iberian Peninsula), where it principally colonizes cliffs. A possible recent hybrid origin for these populations is considered but rejected in view of the results of experimental tests of pollen viability and seed germination. Characters permitting discrimination from the most similar taxa are detailed, and possible relationships with the other species of the section are discussed.  相似文献   
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Factors related to bacterial environment of nests are of primary interest for understanding the causes of embryo infection and the evolution of antimicrobial defensive traits in birds. Nest visitors such as parasites could act as vectors for bacteria and/or affect the hygienic conditions of nests and hence influence the nest bacterial environment. In the present study, we explored some predictions of this hypothetical scenario in the great spotted cuckoo (Clamator glandarius)–magpie (Pica pica) system of brood parasitism. Great spotted cuckoos visit the nests of their magpie hosts and frequently damage some of the host eggs when laying eggs or on subsequent visits. Therefore, it represents a good system for testing the effect of nest visitors on the bacterial environment of nests. In accordance with this hypothesis, we found that the bacterial load of magpie eggshells was greater in parasitized nests, which may suggest that brood parasitism increases the probability of bacterial infection of magpie eggs. Moreover, comparisons of bacterial loads of cuckoo and magpie eggs revealed that: (1) cuckoo eggshells harboured lower bacterial densities than those of their magpie hosts in the same nests and (2) the prevalence of bacteria inside unhatched eggs was higher for magpies than for great spotted cuckoos. These interspecific differences were predicted because brood parasitic eggs (but not host eggs) always experience the bacterial environments of parasitized nests. Therefore, the results obtained in the present study suggest that parasitic eggs are better adapted to environments with a high risk of bacterial contamination than those of their magpie hosts. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 103 , 836–848.  相似文献   
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We compared 42 phylogenetically conserved proteins from four marine sponges [Porifera] with almost the complete set of Caenorhabditis elegans proteins and all known proteins from humans. The majority of the sponge proteins arc significantly more similar to human than to C. elegans orthologucs/homologues. This finding reflects the accelerated evolutionary rate in the C. elegans lineage, since sponges split off first from the common ancestor of all multicellular animals. Furthermore, three sponge/human proteins were not found in C. elegans: (2–5)A synthetase, DNA repair helicase and lens βγ-crystallin. Sponges arc the source of the most ancient proteins already present in the common ancestor of all multicellular organisms. Some of these proteins were lost later during the evolution of individual animal lineages. These 'found/lost' proteins may serve as molecular markers for an improved systematics of Metazoa. In addition, phylogenetically conserved sponge proteins can be very helpful for the evaluation of differences in evolutionary rates in different animal lineages. We therefore propose sponges as the reference animals in molecular evolutionary studies of Metazoa.  相似文献   
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