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1.
Danaea tuomistoana A. Rojas (Marattiaceae) is described and illustrated as a new species endemic to Costa Rica; it differs from D. crispa Endres et Richb. by a truncate blade, and by the pinnae, which are 2/5-1/2 incised, cuneated at the base and with a flat margin. The range of D. erecta H. Tuomisto & R.C. Moran in Costa Rica is expanded with a new locality in Puntarenas (8 degrees 57'15" N-82 degrees 50'1" W, 1,500-1,580 masl).  相似文献   

2.
Revision of the Neotropical fern genus Danaea (Marattiaceae) has resulted in the recognition of ten new species, which are here for the first time presented to the scientific audience. Morphological and molecular data suggest that the genus consists of three monophyletic subgenera that are circumscribed here. A key is provided to aid species identification. The geographical ranges of the species are summarized and discussed with regard to speciation. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 163 , 360–385.  相似文献   

3.
4.
Polotow, D. & Brescovit, A. D. (2010). Phylogenetic relationships of the Neotropical spider genus Itatiaya (Araneae). —Zoologica Scripta, 40, 187–193. A cladistic analysis using parsimony under equal weights is applied to test the phylogenetic relationships of Itatiaya Mello‐Leitão, previously described in Ctenidae. The data matrix comprised 25 taxa scored for a total of 47 characters. The cladistic analysis yielded two equally parsimonious trees of 124 steps. The consensus of the two most parsimonious trees is used to discuss the phylogenetic relationships and justify taxonomic modifications. The results indicate that this genus is a representative of Zoropsidae, which is newly recorded from the Neotropical region. The monophyly of Itatiaya is supported by three non‐ambiguous synapomorphies and three homoplastic synapomorphies. A new diagnosis is provided for Itatiaya. Itatiaya pucupucu is placed as sister species to the remaining species of the genus. A polytomic clade composed of Itatiaya modesta, Itatiaya iuba, Itatiaya apipema and the clade formed by Itatiaya tacamby + Itatiaya pykyyra is supported by the presence of modified cylindrical gland spigots. Additionally, the male of I. pykyyra Polotow & Brescovit is described for the first time.  相似文献   

5.
The Oriental vessel fern, Angiopteris evecta (G.Forst.) Hoffm. (Marattiaceae), has its native range in the South Pacific. This species has been introduced into other localities since the 18th century and is now listed as an invasive species in several regions (Jamaica, Hawaii and Costa Rica). The purpose of our study is (1) to trace the distributional history of the species, and (2) to model its potential future range based on climatic conditions. The native range and the history of introduction are based on the existing literature and on 158 specimens from 15 herbaria, together with field observations. As there are taxonomic problems surrounding A. evecta, we limited our analysis to samples from the Pacific, most closely resembling the type from Tahiti. We modelled the potential range using GARP species distribution modelling with basic climatic variables, elevation, and location in relation to the coast. Analysis of past records shows that the species is able to colonise new ecosystems with relative ease. The modelling reveals that the species could be cultivated over a much wider range than where it currently is grown. The escape of cultivated plants into nature is probably due to distance from natural areas and is limited by local ecological factors, such as soil conditions or competitors. The predicted distribution in Asia and Madagascar is similar to the native distribution of the entire genus Angiopteris. It can therefore be assumed that most Angiopteris species have similar climatic preferences, and the absence of A. evecta in this predicted region may be due to dispersal limitation. In the Americas there is no native Angiopteris, but our climatic model predicts a vast potential habitat in tropical America; an invasion of A. evecta should be anticipated here in localities where the species is cultivated. Vessel ferns are known to alter the natural environment, which may reduce local biodiversity. Since A. evecta is not yet widely cultivated, it is advisable to restrict the trade and spread of the species and to discourage its cultivation as an ornamental. The global climate data available for modelling is however not detailed enough to predict the spread of A. evecta on a local or regional scale.  相似文献   

6.
Adaptation to host-plant defences through key innovations is a driving force of evolution in phytophagous insects. Species of the neotropical bruchid genus Acanthoscelides Schilsky are known to be associated with specific host plants. The speciation processes involved in such specialization pattern that have produced these specific associations may reflect radiations linked to particular kinds of host plants. By studying host-plant associations in closely related bruchid species, we have shown that adaptation to a particular host-plant (e.g. with a certain type of secondary compounds) could generally lead to a radiation of bruchid species at the level of terminal branches. However, in some cases of recent host shifts, there is no congruence between genetic proximity of bruchid species, and taxonomic similarity of host plants. At deeper branches in the phylogeny, vicariance or long-distance colonization events seem to be responsible for genetic divergence between well-marked clades rather than adaptation to host plants. Our study also suggests that the few species of Acanthoscelides described from the Old World, as well as Neotropical species feeding on Mimosoideae, are misclassified, and are more closely related to the sister genus Bruchidius .  相似文献   

7.
The phylogenetic relationships of Hymenophyllum and its segregate genera Cardiomanes, Hymenoglossum, Rosenstockia, Serpyllopsis and Microtrichomanes are addressed, using 31 morphological characters of the sporophyte and one cytological character. As expected, this study reveals considerable morphological heterogeneity within the genus sensu lato, but several apomorphic changes allow support for some clades. Four unresolved taxa, Cardiomanes, Hymenoglossum, Diplophyllum and Mecodium pro parte are probably the most basal elements in Hymenophyllum. The analysis also suggests the polyphyly of Mecodium, and two unexpected associations: Sphaerocionium together with Microtrichomanes; and a broad clade composed of subg. Hymenophyllum, Hemicyatheon and Craspedophyllum, genera Rosenstockia and Serpyllopsis, and subsect. Leptocionium and Amphipterum. These associations appear justified by morphological, cytological or geographical data, and most of them are in agreement with preliminary molecular results.  相似文献   

8.
Of the seven genera which we have recognised within the Archiloa genus complex sensu Karling (1966) the cosmopolitan genus Archilina is the most primitive and is characterised only by plesiomorphic characters, and has to be considered paraphyletic. All other species of the Archiloa genus complex are hypothesized to be derived from Archilina-like ancestors through different evolutionary lineages. One lineage led to the genera Archiloa, Inaloa, Archilopsis and Monocelopsis, taxa found in the Atlantic and the Mediterranean. These genera are monophyletic and their relationships are analyzed. The genera Mesoda (Brazil) and Tajikina (Northern Pacific) can be considered as two other separate lineages. Similarly, within what we now consider as the genus Archilina different lineages can be recognized in different regions.  相似文献   

9.
The Marattiaceae are represented by a small family of four to six genera that bear esporogenous structures of two types: sorus with free eusporangia in Angiopteris and Archangiopteris, and indurated synangium in Christensenia, Danaea and Marattia. Marattia is a pantropical genus of about eight to ten species in the paleotropic and seven to eight species in the neotropic. In order to describe the spores and sinangia morphology, this study analyzed the shape of the receptacles, and the position of the synangia, and evaluated the spores with SEM, of seven neotropical species of the genus Marattia: M. alata, M. cicutifolia, M. excavata, M. interposita, M. laevis, M. laxa y M. weinmanniifolia from several collections. The receptacles were fully developed in M. cicutifolia and M. laevis, and scarcely overelevated in the rest of the species. The synangium was ellipsoidal and had intramarginal to supramedial position in the laminae. The spores of Marattia were elliptic. Among the taxa, only monolete spores were found, with no trilete, aborted or deformed spores. The laesura was linear and reached about two of the total length of the spore. The perispore appears as a continuous thin layer deposited on the exospore according to its ornamentation in M. cicutifolia and M. laevis. It is smooth in M. alata, rugate in M. excavata and pustulate-rugate in two species: M. interposita and M. laxa. The exospore is echinate in M. cicutifolia and M. laevis and pustulate in the other species. In M. weinmannifolia spores produced by the same sinangium may have different ornamentation types. We concluded that, while the presence of ellipsoidal and superficial synangia and monolete spores aperture were generic traits, the micro and macro-ornamentation types of the perispores and exospores vary at specific level. Besides, macro-ornamentation can be bulliform (pustulate), a combination of bulliform and muriform types (pustulate-rugate), muriform (rugate-retate) and stelliform (echinate); finally, granular micro-ornamentation can be seen frecuently in perispores.  相似文献   

10.
Evolutionary relationships in the genus Bordetella   总被引:3,自引:0,他引:3  
The nucleotide sequence of the pertussis toxin operon of Bordetella pertussis, Bordetella parapertussis and Bordetella bronchiseptica, has shown that the last two species contain many common mutations and are likely to derive from a common ancestor (Aricò and Rappuoli, 1987). To elucidate further the evolutionary relationships between the Bordetella species, we have cloned and sequenced the promoter region and the gene coding for the S1 subunit of pertussis toxin from additional B. pertussis strains, such as the type strain BP 18323 and two recent clinical isolates, namely strain BP 13456 from Sweden and strain BP SA1 from Italy. While the strains BP SA1 and BP 13456 are shown to differ from the published B. pertussis sequences by only one base pair, the type strain BP 18323 contains a total of 11 base-pair substitutions. Remarkably, 9 of the 11 substitutions found in BP 18323 are also common to B. parapertussis and B. bronchiseptica, strongly suggesting that this strain derives from the same ancestor as B. parapertussis and B. bronchiseptica. Computer analysis of the sequence data allows the construction of an evolutionary 'tree' showing that the B. pertussis strains are very homogeneous and significantly distant from B. parapertussis and B. bronchiseptica. Therefore the proposed conversion from B. parapertussis to B. pertussis appears highly improbable.  相似文献   

11.
Evolutionary relationships in the genus Bordetella   总被引:12,自引:4,他引:8  
The nucleotide sequence of the pertussis toxin operon of Bordetella pertussis, Bordetella parapertussis and Bordetella bronchiseptica, has shown that the last two species contain many common mutations and are likely to derive from a common ancestor (Arico and Rappuoli, 1987). To elucidate further the evolutionary relationships between the Bordetella species, we have cloned and sequenced the promoter region and the gene coding for the S1 subunit of pertussis toxin from additional B. pertussis strains, such as the type strain BP 18323 and two recent clinical isolates, namely strain BP 13456 from Sweden and strain BP SA1 from Italy. While the strains BP SA1 and BP 13456 are shown to differ from the published B. pertussis sequences by only one base pair, the type strain BP 18323 contains a total of 11 base-pair substitutions. Remarkably, 9 of the 11 substitutions found in BP 18323 are also common to B. parapertussis and B. bronchiseptica, strongly suggesting that this strain derives from the same ancestor as B. parapertussis and B. bronchiseptica. Computer analysis of the sequence data allows the construction of an evolutionary ‘tree’ showing that the B. pertussis strains are very homogeneous and significantly distant from B. parapertussis and B. bronchiseptica. Therefore the proposed conversion from B. parapertussis to B. pertussis appears highly improbable.  相似文献   

12.
13.
A new retiolitid genus Cometograptus, restricted to the lundgreni Biozone (Late Wenlock), is characterized by a combination of primitive features such as strong transverse rods and ancora sleeve lists with seams facing out, with advanced features such as a long sicula, central, free nema and pustulose bandages. Cometograptus links two Subfamilies of the Family Retiolitidae. The Subfamily Retiolitinae is divided into redefined lineages: Pseudoretiolites, Retiolites, Paraplectograptus, whereas the Subfamily Plectograptinae is divisible into the Sokolovograptus (questionable), Gothograptus, Spinograptus, Plectograptus lineages, and Cometograptus. The Sokolovograptus group, the first retiolitids bearing ancora sleeve lists with seams facing out, did not survive the lundgreni crisis. The only survivors were Upper Wenlock retiolitids of the Gothograptus lineage. The new genus Cometograptus includes Cometograptus koreni n.gen. and n.sp., Cometograptus tomczyki n.gen. and n.sp., as well as the previously described Cometograptus nevadensis, Cometograptus marsupium and Cometograptus apoxys.  相似文献   

14.
15.
Aim We investigate spatial and temporal patterns of diversification within the Neotropical avifauna using the phylogenetic history of parrots traditionally belonging to the genus Pionopsitta Bonaparte 1854. This genus has long been of interest for those studying Neotropical biogeography and diversity, as it encompasses species that occur in most Neotropical forest areas of endemism. Location The Neotropical lowland forests in South and Central America. Methods Phylogenetic relationships were investigated for all species of the genus Pionopsitta and five other short‐tailed parrot genera using complete sequences of the mitochondrial genes cyt b and ND2 as well as 26 plumage characters. The resulting phylogeny was used to test the monophyly of the genus, investigate species limits, and as a framework for reconstructing their historical biogeography and patterns of diversification. Results We found that the genus Pionopsitta, as previously defined, is not monophyletic and thus the Chocó, Central American and Amazonian species will now have to be placed in the genus Gypopsitta. The molecular and morphological phylogenies are largely congruent, but disagree on the position of one of the Amazon basin taxa. Using molecular sequence data, we estimate that species within Gypopsitta diversified between 8.7 and 0.6 Ma, with the main divergences occurring between 3.3 and 6.4 Ma. These temporal results are compared to other taxa showing similar vicariance patterns. Main conclusions The results suggest that diversification in Gypopsitta was influenced mainly by geotectonic events, marine transgressions and river dynamics, whereas Quaternary glacial cycles of forest change seem to have played a minor role in the origination of the currently recognized species.  相似文献   

16.
Species of the cichlid genera Tilapia, Sarotherodon and Oreochromis were studied by electrophoresis at 25 enzyme loci. The levels of similarities within and between genera, and the distribution of genetic identities at individual loci are similar to those found in other fish species. The evolutionary relationships between the species remains equivocal, and it is still not possible to decide between the hypotheses of Trewavas (1980) or that of Peters & Berns (1978, 1982). Further work needs to be undertaken on additional Tilapia and Sarotherodon species. The unexpected relationship of O. jipe to the other Oreochromis species is probably the strongest argument against Trewavas' hypothesis. But the close similarity of the maternal mouth brooders to each other, and the closer relationship of S. galilaeus to the Oreochromis species than to the Tilapia does not favour the hypothesis of Peters & Berns (1982). The difficulties in obtaining pure species from the wild due to widespread introduction of non-endemic species are likely to hinder progress in evolutionary and aquacultural studies.  相似文献   

17.
Ren TH  Chen F  Zou YT  Jia YH  Zhang HQ  Yan BJ  Ren ZL 《Génome》2011,54(4):316-326
Eleven weedy or wild species or subspecies of the genus Secale L. were compared with a set of cultivated rye accessions, based on inter-simple sequence repeat (ISSR) markers to analyze their phylogenetic relationships. A total of 846 bands were amplified from reactions using 12 screening primers, including 79 loci with a mean of 10.1 alleles per locus. The number of amplified bands for each primer ranged from 12 to 134, with a mean of 70.5 amplified bands per primer. The presence and distribution of amplified bands in different accessions demonstrate that a rapid evolutionary trend of microsatellite repeats occurred during the speciation process from the perennial wild form to annual cultivated rye. In addition, variation, amplification, and deletion of microsatellites in genomes revealed phylogenetic relationships in the genus Secale. Analysis of the presence, number, and distribution of amplified bands in genomes, as well as the comparison with genetic similarity (GS) indices based on ISSR, indicate that Secale strictum subsp. africanum (Stapf) Hammer, Secale strictum anatolicum (Boiss.) Hammer, Secale sylvestre Host, and Secale strictum subsp. strictum (C. Presl) Hammer emerged in succession from a common ancestor of Secale following geographic separation and genetic differentiation. The annual weedy rye evolved from S. strictum subsp. strictum, which was domesticated as present-day cultivated rye. Data from ISSR analyses separated all investigated accessions of the genus Secale into three distinct groups. These results support the division of the genus Secale into three species: the annual wild species S. sylvestre; the perennial wild species S. strictum, including several differential subspecies forms such as strictum, africanum, and anatolicum; and S. cereale, including cultivated and weedy rye as subspecies forms.  相似文献   

18.
Chromosome study of the fern genus Cyrtomium (Dryopteridaceae)   总被引:1,自引:0,他引:1  
Cyrtomium (Dryopteridaceae) is an Asiatic genus comprising about 40 species characterized by having anastomosing veins that form areolae with included veinlets. Twelve chromosome counts representing 11 taxa were made in the present study. The chromosome numbers of six species endemic to China are reported for the first time: C. uniseriale , 2 n  = 164; C. guizhouense , 2 n  = 82; C. shingianum , n  = 82, 2 n  =  c .164; C. chingianum , 2 n  = 164; C. urophyllum , 2 n  = 82 and C. aequibasis , 2 n  = 123. The results were used to show that (1) C. uniseriale should be reduced to varietal status under C. balansae ; (2) subseries Balansana is not closely related to any other Cyrtomium species and should be separated from Cyrtomium ; and (3) C. guizhouense and C. lonchitoides are basal groups when subseries Balansana is not considered. These results were also supported by morphology. A high level of differentiation is a distinct characteristic in Cyrtomium . The genus has two reproductive types: sexual and apogamous. Sexual species are distributed mostly in China. Southwestern China is a modern diversity centre of Cyrtomium , with 80.6% of known species occurring there. Many species are endemic, most of which are sexual tetraploids or apogamous triploids. Both the apogamous reproductive type and polyploid species are adaptions to limestone habitats.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 150 , 221–228.  相似文献   

19.
Species diversity and morphological disparity are two measures to examine the diversity of life. Evidence based on the fossil record suggests a complex relation between these two parameters of biodiversity including frequent decoupling of their assembly through time. However, rather few studies explored the correlation of these two measurements by studying extant plant species. This study was designed to explore the accumulation of morphological disparity of the derived Neotropical fern genus Pleopeltis. To explore the relationship of species diversity and morphological disparity, we employed several approaches including divergence time estimates based on DNA sequence variation, reconstruction of character state changes based on a morphological matrix comprising 41 discrete characters, and exploration of the phylomorphospace. Accumulation of species diversity and morphological disparity was found to be concordant although the assumption of independence was not rejected for the accumulation of genetic and morphological variation. The phylomorphospace reconstruction provided further evidence for clade‐specific morphospace expansion that imply developmental pathways and competition among clades as major factors shaping the assembly of morphological disparity over time.  相似文献   

20.
Scanning electron microscopy (SEM) of tracheary elements of roots of five species from four genera of Marattiaceae and of the rhizome of one species revealed vessel elements present in all. The secondary wall framework of perforation plates is the same as that of lateral wall pitting for vessel elements in all species. Thus, no specialization is present in perforation plates of Marattiaceae compared to the simplified morphology of perforation plates of some leptosporangiate ferns (e.g., Dryopteridaceae, Polypodiaceae, and Pteridaceae). The difference between lateral wall pitting and perforation plates in tracheary elements of Marattiaceae cannot be seen by light microscopy (in which pit membranes are transparent), but is evident with SEM. Diversity in structure of perforation plates (especially the alternation of wide and narrow perforations within a plate) and presence of web-like pit membrane remnants are evident. Vessels are widespread in both leptosporangiate and eusporangiate ferns, although specialization in perforation plates (e.g., bars few and more widely spaced in lateral wall pitting of a given vessel element) is to be expected only in ferns of habitats with marked fluctuation in water availability. Vessels of Marattiaceae lack such specializations and are thus are correlated with the mesic habitats characteristic for the family.  相似文献   

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