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1.
Systematics within the genus Trichomanes sensu lato (Hymenophyllaceae, Filicopsida) have continued to be controversial because of the difficulty in identifying homologies and informative characters within high morphological diversity. Systematic relationships are investigated in this study by using a cladistic approach with 31 anatomical and morphological characters from 20 taxa which correspond to the sections defined by Morton. The results broadly confirm Morton's four subgenera: Trichomanes, Didymoglossum, Pachychaetum and Achomanes. The monophyly of Pachychaetum remains fragile and the section Lacostea appears to be excluded from its traditional subgenus (Achomanes). In addition, by producing two major 'ecological' clades (terrestrial and epiphytic), the analysis shows that several selected characters appear to be strongly linked with the ecology which may have a significant influence on the topology.  相似文献   
2.
We use an integrative taxonomic approach to revise the genus Anisopteromalus. In particular, we apply multivariate ratio analysis (MRA), a rather new statistical method based on principal component analysis (PCA) and linear discriminant analysis (LDA), to numerous body measurements and combine the data with those from our molecular analysis of Cytb and ITS2 genetic markers (on a subset of species) and all available published data on morphology, karyology, behaviour, host associations and geographic distribution. We demonstrate that the analysis of quantitative characters using MRA plays a major role for the integration of name‐bearing types and thus for the association of taxa with names. Six species are recognized, of which two are new: A. cornis Baur sp.n. and A. quinarius Gokhman & Baur sp.n. For Anisopteromalus calandrae (Howard), a well‐known, cosmopolitan parasitoid of stored‐product pests, we have selected a neotype to foster continuity and stability in the application of this important name. The species was sometimes confused with the related A. quinarius sp.n. , another cosmopolitan species that is frequently encountered in similar environments. We also show that several species originally described or later put under Anisopteromalus actually belong to different genera: Cyrtoptyx camerunus (Risbec) comb.n. ; Meraporus glaber (Szelényi) comb.n. ; Dinarmus schwenkei (Roomi, Khan & Khan) comb.n. Neocatolaccus indicus Ayyar & Mani is confirmed as a junior synonym of Oxysychus sphenopterae (Ferrière) syn.n. and Anisopteromalus calandrae brasiliensis (Domenichini) stat.rev. must be considered as a valid but doubtful taxon. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:BDFE96D3‐D0F4‐4012‐90F5‐9A087F7F5864 .  相似文献   
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The assessment of developmental stability in hybrids can provide valuable information in the study of species formation because it allows an evaluation of the degree of incompatibility of genetic systems that control developmental processes. The present study assessed the impact of two hybridization events, assumed to have occurred at different times, on developmental instability in the ground beetle Carabus solieri . Developmental instability was estimated in 678 individuals from 27 populations from the fluctuating asymmetry (FA) levels of four morphological traits: the tibia length of middle and hind legs, which are functional structures, and the length and the proximal width of the hind wings, which are vestigial and thus nonfunctional structures. Significant variations of FA levels between populations were shown only for the wing width. For this trait, FA levels in hybrids were higher than in their parental entities for both hybridization events, indicating a significant divergence of the gene systems controlling development between the parental entities in the two hybridization cases. As expected, wing traits exhibited FA levels at least three times higher than leg trait. Finally, the potential interest of vestigial traits in the particular context of hybridization is discussed.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 89 , 151–158.  相似文献   
5.
To establish a basis for future taxonomic revisions and to infer the evolutionary traits of Trichomanes s.l. , one of two large filmy fern genera, molecular phylogenetic analyses were conducted using chloroplast rbcL sequences. Sampling covered most of the global distribution range of this genus throughout the tropical and temperate zones, as well as all taxonomically significant species by the addition of 51 samples principally from Asia. The evolution of eight selected characters, which were adopted as taxonomic keys and/or putatively reflect morphological regression, was optimized on the retrieved most parsimonious rbcL trees, together with new observations on the stem anatomy of 45 species. The eight robust clades retrieved within Trichomanes in the rbcL phylogeny conflict with the existing classifications. Our results also suggest that the cup-shaped sorus, the primary diagnostic character of the genus, appears in parallel in the Hymenophyllum lineage, as demonstrated by Pleuromanes (typified by Trichomanes pallidum ) included in the lineage. The suggestion that the regressive character states are homoplastic apomorphies in the evolution of the frond size, stem thickness, root system, and stem anatomy (stele and cortex) probably illustrates a strong tendency towards adaptive evolutionary transition in Trichomanes . © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 1–27.  相似文献   
6.
The lack of information on the ways seasonal drought modifies the CO2 exchange between Neotropical rainforest ecosystems and the atmosphere and the resulting carbon balance hinders our ability to precisely predict how these ecosystems will respond as global environmental changes force them to face increasingly contrasting conditions in the future. To address this issue, seasonal variations in daily net ecosystem productivity (NEPd) and two main components of this productivity, daily total ecosystem respiration (REd) and daily gross ecosystem productivity (GEPd), were estimated over 2 years at a flux tower site in French Guiana, South America (5 °16′54″N, 52 °54′44″W). We compared seasonal variations between wet and dry periods and between dry periods of contrasting levels of intensity (i.e. mild vs. severe) during equivalent 93‐day periods. During the wet periods, the ecosystem was almost in balance with the atmosphere (storage of 9.0 g C m?2). Seasonal dry periods, regardless of their severity, are associated with higher incident radiation and lower REd combined with reduced soil respiration associated with low soil water availability. During the mild dry period, as is normally the case in this region, the amount of carbon stored in the ecosystem was 32.7 g C m?2. Severe drought conditions resulted in even lower REd, whereas the photosynthetic activity was only moderately reduced and no change in canopy structure was observed. Thus, the severe dry period was characterized by greater carbon storage (64.6 g C m?2), emphasizing that environmental conditions, such as during a severe drought, modify the CO2 exchange between Neotropical rainforest ecosystems and the atmosphere and potentially the resulting carbon balance.  相似文献   
7.
Besides the pollinators (Agaonidae), several chalcidoid lineages of nonpollinating fig wasps are strictly dependent on Ficus (Moraceae) for reproduction. Overall, nonpollinating fig wasps have not received much consideration. Reliable phylogenetic and taxonomic frameworks are lacking for most groups, which hampers progress in our understanding of the evolution and functioning of fig wasp communities. Here we focus on Anidarnes Bou?ek (Sycophaginae), a member of the Neotropical fig wasp community. We present a detailed morphological analysis as well as the first molecular phylogeny of the genus inferred from two nuclear and two mitochondrial genes (Cytb, COI, EF‐1α and 28S rRNA, 3937 bp). Twelve species are recognised, illustrated and a key to their identification is provided. Of those, only three were previously described and are redescribed here: A. bicolor (Ashmead); A. globiceps (Mayr) and A. brevicauda Bou?ek. In addition, nine new species are described: Anidarnes brevior sp.n . Farache & Rasplus (Costa Rica); A. dissidens sp.n. Farache & Rasplus (Brazil); A. gracilis sp.n. Farache & Rasplus (Costa Rica); A. isophlebiae sp.n. Farache & Rasplus (Costa Rica); A. jimeneziae sp.n. Farache & Rasplus (Costa Rica); A. longiscutellum sp.n. Farache & Rasplus (Brazil); A. martinae sp.n. Farache & Rasplus (U.S.A., Florida); A. nigrus sp.n. Farache & Rasplus (Colombia) and A. rugosus sp.n. Farache & Rasplus (Brazil). Finally, phylogenetic relationships inferred using parsimony, bayesian and maximum likelihood methods are discussed in the light of our morphological observations and the host fig tree taxonomy.  相似文献   
8.
The subgenus Mesocarabus Thomson, 1875 is a western Palaearctic group that currently includes five species: four of them inhabiting western Europe (Carabus lusitanicus Fabricius, 1801, Carabus problematicus Herbst, 1786, Carabus dufourii Dejean & Boisduval, 1829, and Carabus macrocephalus Dejean, 1826) and one found in the Rif Mountains in northern Morocco (Carabus riffensis Fairmaire, 1872). Representatives of Mesocarabus have been included in previous molecular phylogenetic studies, but taxon‐ or gene‐sampling limitations yielded inconclusive results regarding its monophyly and sister relationship. Here we perform molecular phylogenetic analyses based on five mitochondrial (3625 nt) and eight nuclear (5970 nt) genes sequenced in many Mesocarabus populations, and in related western Palaearctic Carabus Linnaeus, 1758. We conducted parsimony, maximum‐likelihood, and Bayesian analyses and found a well‐supported sister relationship between a monophyletic Mesocarabus with Iberian species of the subgenus Oreocarabus Géhin, 1876. Within Mesocarabus, the European species form a monophyletic lineage sister to Moroccan C. riffensis. A time‐calibrated phylogeny suggests the split between Mesocarabus and Oreocarabus occurred at 11.8 Mya (95% highest posterior density, HPD, 8.7–15.3 Mya), and the divergence between C. riffensis and European Mesocarabus at 9.5 Mya (95% HPD 7.0–12.5 Mya). The early diversification of Mesocarabus and related subgenera during the Miocene, and alternative hypotheses concerning the origin of Mesocarabus in the Iberian Peninsula and the Betic‐Riffian plate are discussed using calibration data and dispersal–vicariance biogeographic analyses. Finally, we found instances of incongruence between mitochondrial DNA and nuclear‐based phylogenies of Mesocarabus, which are hypothesized to be the result of introgressive hybridization. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 166 , 787–804.  相似文献   
9.
Among the basal fern families, the Hymenophyllaceae, with more than 600 species, display a high diversity in terms of their morphology and the habitats that they occupy. We have chosen to focus on Trichomanes L., a clearly defined genus for which a phylogeny is presently being developed, to investigate the appearance of the climbing and epiphytic habits, as well as the related supposed adaptive characters. In this study we present the first review of the different ecological types within the genus: terrestrial, climbing (divided into hemi-epiphytic forms and true lianas), and epiphytic types. The study of several features concerning stem morphology and leaf size allows a proposal on relationships between ecology and plant morphology. Terrestrial species display a thick monocaulous rhizome with robust roots and short internodes. Climbing species are characterized by a branched, thick, creeping rhizome with long internodes. Epiphytic species also exhibit long, creeping and branching stems with long internodes but the rhizome is fine to filiform. Under these circumstances, there is a reduction of root system and frond size leading to dwarfism in numerous instances. This may be related to an extreme hygrophilous epiphytic strategy. Finally, hypotheses on the evolution of these habits and hence on the evolutionary relationships between ecology and characters are presented and discussed.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 142 , 41–63.  相似文献   
10.
A phylogenetic study of the Eurytominae (Hymenoptera: Chalcidoidea) treating 178 taxa and based on 150 morphological characters is given. Several cladograms using the complete species sample, but obtained with different weightings, are presented. Local studies were also carried out to provide possible alternate topologies. The deep nodes of the trees were unstable and were never supported, but most of the superficial nodes were stable and robust. The results therefore provide support for a generic classification of the subfamily. The large genus Eurytoma– which includes about half of the described species of the subfamily – proved to be polyphyletic, and is redefined in a narrowed sense using putative synapomorphies. Bruchophagus and Prodecatoma were similarly redefined. The genera Philolema and Aximopsis are reconsidered and defined in a broader concept. A number of the species presently included in Eurytoma were transferred to these genera. Finally, 22 new generic synonymies are proposed and 33 species are transferred. The study also demonstrates that the Eurytomidae are polyphyletic. The results strongly support a sister‐group relationship between the Heimbrinae and the Chalcididae. The Rileyinae consist of two groups of unrelated taxa. A redefinition of the subfamily in a more restricted sense is supported by our results. The remaining group, consisting of the traditional Rileyinae, is included in the subfamily Buresiinae. Considered in this way they comprise the genera Buresium and Macrorileya, the latter being a senior synonym of Archirileya. The Buresiinae appear as the sister group of the Eurytominae. We propose to restrict the family Eurytomidae to these two taxa. This sister‐group relationship provides evidence to polarize the biological habits within Eurytominae. The common ancestor of Buresiinae is presumed to parasitize insects (mostly at the egg stage) living in grass stems. © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society, 2007, 151 , 441–510.  相似文献   
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