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1.
Despite progress in clarifying the relationships of Dasypogonaceae (four genera, Baxteria, Calectasia, Dasypogon, and Kingia), their infrafamilial relationships and precise affinities within the commelinid clade remain unsatisfactorily resolved. This paper reviews existing data on the systematic affinities of Dasypogonaceae. It also presents new data on floral structure in all four genera, and data on floral ontogeny in Dasypogon. In Dasypogon, Kingia, and Baxteria the ovary is trilocular and septal nectaries are present around the ovary base. In Calectasia, the ovary is unilocular and septal nectaries are entirely absent. Two subfamilial groupings within Dasypogonaceae (CalectasiaDasypogon and BaxteriaKingia) are proposed on the basis of leaf anatomy and ovule and ovary morphology. Many floral characters are plesiomorphic in Dasypogonaceae, but some morphological characters support a close relationship with the order Poales sensu lato, especially the epidermal location of the silica bodies. The unusual long-stalked “drumstick” inflorescences of Dasypogon and Kingia resemble those of some Poales, in which flowers are frequently borne on condensed inflorescences. A possible close relationship between Dasypogonaceae and some Poales such as Rapateaceae and Thurniaceae merits further exploration.  相似文献   

2.
The proposal to restructure the genus Arcobacter into six distinct genera was critically examined using: comparative analyses of up to 80 Epsilonproteobacterial genome sequences (including 26 arcobacters); phylogenetic analyses of three housekeeping genes and also 342 core genes; and phenotypic criteria. Genome sequences were analysed with tools to calculate Percentage of Conserved Proteins, Average Amino-acid Identity, BLAST-based Average Nucleotide Identity, in silico DNA–DNA hybridisation values, genome-wide Average Nucleotide Identity, Alignment Fractions and G + C percentages. Genome analyses revealed the genus Arcobacter sensu lato to be relatively homogenous, and phylogenetic analyses clearly distinguished the group from other Epsilonproteobacteria. Genomic distinction of the genera proposed by Pérez-Cataluña et al. [2018] was not supported by any of the measures used and a subsequent risk of strain misidentification clearly identified. Similarly, phenotypic analyses supported the delineation of Arcobacter sensu lato but did not justify the position of the proposed novel genera. The present polyphasic taxonomic study strongly supports the continuance of the classification of “aerotolerant campylobacters” as Arcobacter and refutes the proposed genus-level subdivision of Pérez-Cataluña et al. [2018].  相似文献   

3.
Generic concepts in the economically important agarophyte red algal family Gracilariaceae were evaluated based on maximum parsimony, Bayesian likelihood, and minimum evolution analyses of the chloroplast‐encoded rbc L gene from 67 specimens worldwide. The results confirm the monophyly of the family and identify three large clades, one of which corresponds to the ancestral antiboreal genera Curdiea and Melanthalia, one to Gracilariopsis, and one to Gracilaria sensu lato, which contains nine distinct independent evolutionary lineages, including Hydropuntia. The species currently attributed to Hydropuntia comprise a single well‐supported clade composed of two distinct lineages. The two most basal clades within Gracilaria sensu lato deserve generic rank: a new genus centered around G. chilensis Bird, McLachlan et Oliveira and G. aff. tenuistipitata Chang et Xia and a resurrected Hydropuntia encompassing primarily Indo‐Pacific (G. urvillei [Montagne] Abbott, G. edulis [S. Gmelin] P. Silva, G. eucheumatoides Harvey, G. preissiana [Sonder] Womersley, and G. rangiferina [Kützing] Piccone) and western Atlantic species (G. cornea J. Agardh, G. crassissima P. et H. Crouan in Mazé et Schramm, G. usneoides [C. Agardh] J. Agardh, G. caudata J. Agardh, and G. secunda P. et H. Crouan in Mazé et Schramm). Cystocarpic features within the Gracilaria sensu lato clades appear to be more phylogenetically informative than male characters. The textorii‐type spermatangial configuration is represented in two distinct clusters of Gracilaria. The rbc L genetic divergence among the Gracilariaceae genera ranged between 8.46% and 16.41%, providing at least 2.5 times more genetic variation than does the 18S nuclear rDNA. rbc L also resolves intrageneric relationships, especially within Gracilaria sensu lato. The current number of gracilariacean species is underestimated in the western Atlantic because of convergence in habit and apparent homoplasy in vegetative and reproductive anatomy.  相似文献   

4.
The flower bugs or minute pirate bugs, Anthocoridae sensu lato, are represented by 12 genera and 24 species in the Korean Peninsula. The present catalog includes three newly recorded species to the fauna: Anthocoris confusus Reuter, Bilia japonica Carayon et Miyamoto, and Montandoniola pictipennis (Esaki). Distributional data and bibliographical references of each taxon are included. Biological notes (habitats, prey types, etc.) and diagnoses based on the local materials of the Korean Peninsula are also presented for the field of applied entomology.  相似文献   

5.
Phylogenetic relationships of Asphodelaceae were investigatedby parsimony analysis of 57 monocotrbcL nucleotide sequences,including 17 genera that have at some time been assigned tothe family. All genera of Asphodelaceae except for three (Hemiphylacus,Paradisea and Simethis) form a strongly supported monophyleticgroup with Hemerocallidaceae and Xanthorrhoeaceae as their immediatesister taxa. In a second analysis, we added 34 plastid trnL-Fsequences (an intron and a spacer between two transfer RNA genes)for the Asphodelaceae clade and nearest outgroup families (Doryanthaceae,Hemerocallidaceae, Iridaceae, Ixioliriaceae, Tecophilaeaceaeand Xanthorrhoeaceae) in an attempt to improve resolution andlevels of internal support. The results from the separate analysesproduced highly similar although not identical results. No stronglysupported incongruent groups occurred, and we combined bothsequence regions in one analysis, which demonstrated improvedresults. Strong support exists for a monophyletic subfamilyAlooideae, but this leaves a paraphyletic subfamily Asphodeloideaebecause Bulbine/Jodrellia alone are strongly supported as thesister group of Alooideae. Characters that have been used toseparate Alooideae as a distinct group (either as here a subfamilyor as a separate family by other authors), such as secondarygrowth and bimodal karyotypes, are found in at least some membersof Asphodeloideae, particularly in Bulbine and Jodrellia forthe karyotypes, making Alooideae less easily recognized. Copyright2000 Annals of Botany Company Alooideae, Asphodeloideae, Asphodelaceae, Asparagales, phylogenetic analysis, rbcL, trnL-F, molecular systematics  相似文献   

6.
Chromosome numbers are reported for 33 species of the tribe Phaseoleae. Six reports are first counts for their species; one report (Ophrestia hedysaroides) is a first count for the genus. This increases the number of genera counted to 53 out of a total 84 for the tribe. A survey of base numbers shows a general pattern of numbers 10 or 11, the same base numbers as in the neighboring tribes Dalbergieae sensu lato, Galegeae sensu lato, and Abreae. The chromosomes are generally small and polyploidy is uncommon. Deviations from base numbers 10 or 11 are mostly found in those genera with morphological pecularities and puzzling taxonomic placements: Erythrina (21), Clitoria (8, 11, 12), Butea (9), Calopogonium (18), Teramnus (14), and Strongylodon (14). Two genera have base numbers which suggest derivation by polyploidy: Glycine (20) and Cologania (22).  相似文献   

7.
Four decapod crustacean species from the Middle Miocene Mishan Formation of Hormozgan Province, Southern Iran are described. Three species of leucosiid crabs represent the first fossil record for their respective genera outside the Indo-Pacific region. The oldest records for Leucosia sensu lato, Phylira sensu lato, and Arcania are from Middle Miocene deposits of the Indo-Pacific, and thus their paleobiogeographic distribution is extended for this lapse of time. Harpactocarcinus miocenicus n. sp. represents the youngest and most oriental occurrence for a typically Eocene genus, whose species are known mainly from Central Europe. This contribution represents the first formal report for Tertiary crustaceans from Iran.  相似文献   

8.
Molossidae is a large (roughly 100 species) pantropically distributed clade of swift aerially insectivorous bats for which the phylogeny remains relatively unknown and little studied compared with other speciose groups of bats. We investigated phylogenetic relationships among 62 species, representing all extant molossid genera and most of the subgenera, using 102 morphological characters from the skull, dentition, postcrania, external morphology, tongue, and penis, based on direct observation and literature reports. Both parsimony and Bayesian analyses were used in phylogenetic reconstruction. Our analysis supports two main clades of molossids, both of which mingle Old World and New World taxa. One clade is comprised of Mormopterus,Platymops, Sauromys, Neoplatymops, Molossops, Cynomops, Cheiromeles, Molossus, and Promops. The other clade includes Tadarida, Otomops, Nyctinomops, Eumops, Chaerephon, and Mops. The position of Myopterus with respect to these two groups is unclear. As in other recent analyses, we find that several genera do not appear to be monophyletic (e.g. Tadarida, Chaerephon, and Molossops sensu lato). We recommend that the subgenera of Molossops sensu lato and Austronomus be recognized at the generic level. We conclude that much more data are needed to investigate lower level problems (generic monophyly and relationships within genera) and to resolve the higher‐level branching pattern of the family.  相似文献   

9.
Invasive vertebrate species can act as hosts for endemic pathogens and may alter pathogen community composition and dynamics. For the zoonotic pathogen Borrelia burgdorferi sensu lato, the agent of Lyme borreliosis, recent work shows invasive rodent species can be of high epidemiological importance and may support host-specific strains. This study examined the role of gray squirrels (Sciurus carolinensis) (n = 679), an invasive species in the United Kingdom, as B. burgdorferi sensu lato hosts. We found that gray squirrels were frequently infested with Ixodes ricinus, the main vector of B. burgdorferi sensu lato in the United Kingdom, and 11.9% were infected with B. burgdorferi sensu lato. All four genospecies that occur in the United Kingdom were detected in gray squirrels, and unexpectedly, the bird-associated genospecies Borrelia garinii was most common. The second most frequent infection was with Borrelia afzelii. Genotyping of B. garinii and B. afzelii produced no evidence for strains associated with gray squirrels. Generalized linear mixed models (GLMM) identified tick infestation and date of capture as significant factors associated with B. burgdorferi sensu lato infection in gray squirrels, with infection elevated in early summer in squirrels infested with ticks. Invasive gray squirrels appear to become infected with locally circulating strains of B. burgdorferi sensu lato, and further studies are required to determine their role in community disease dynamics. Our findings highlight the fact that the role of introduced host species in B. burgdorferi sensu lato epidemiology can be highly variable and thus difficult to predict.  相似文献   

10.
We investigated the presence ofBorrelia burgdorferi sensu lato inIxodes ricinus ticks collected in a Lyme borreliosis (LB) endemic region of northern Croatia. Ticks (n=124) were collected at five locations and analysed by the polymerase chain reaction (PCR). A DNA fragment from the internal transcribed spacer (ITS2) ofI. ricinus was detected in all tick lysates, indicating that PCR inhibitors were not present.Borrelia burgdorferi sensu lato DNA was detected in 56 out of 124 ticks (45%). Four genomic groups were identified:Borrelia afzelii (n=26),Borrelia garinii (n=5), group VS116 (n=5) andB. burgdorferi sensu stricto (n=1). Mixed infections ofB. afzelii with group VS116 (n=10) andB. afzelii withB. burgdorferi sensu stricto (n=1) were also detected. Eight ticks containedB. burgdorferi sensu lato, which could not be typed. The detection ofB. afzelii andB. garinii in ticks was in agreement with manifestations of LB found locally. The occurrence of group VS116 in northern Croatia and in an earlier study in The Netherlands, infers that this genomic group may be well established in EuropeanI. ricinus.  相似文献   

11.
The actions of red and blue light in the photomovement of chloroplastsand the polarotropic response were studied in the protonemataof the homosporous ferns Pteris vittata L. and Adiantum capillus-venerisL. In Pteris, polarotropism could be induced with blue lightbut not with red light, while both colors of light were effectivein Adiantum protonemata. The photomovement of chloroplasts inthe two species studied by both polarized light and microbeamirradiation, also revealed similar responses to red and bluelight as the polarotropism; i.e. both colors of light were effectivein Adiantum but only blue light was active in Pteris. The resultsin Adiantum were consistent with previous results, which ledto the conclusion that both phytochrome and a blue light-absorbingpigment are involved in the two responses (Kadota et al. 1982,1984, Hayami et al. 1986, Yatsuhashi et al. 1985). By contrast,phytochrome is not involved in either polarotropism or chloroplastmovement in Pteris. Since the phytochrome system is evidentlyactive in every other photoresponses so far investigated inPteris as well as in Adiantum, the present study suggests thata phytochrome system specific to polarotropism and to photomovementof chloroplasts is absent in Pteris. Discussions are presentedon the possible involvement of two phytochrome populations ina fern gametophyte cell and on the possible lack of dichroicphytochrome in Pteris. (Received October 7, 1988; Accepted March 8, 1989)  相似文献   

12.
Members of the bacterial genus Arthrobacter sensu lato are Gram-positive actinomycetes distributed worldwide and found in numerous environments including soil, water, glacier ice, and sewage. Homologous recombination is an important driving force in bacterial evolution, but its impact on Arthrobacter sensu lato evolution is poorly understood. We evaluated homologous recombination among 41 Arthrobacter sensu lato named species, using multilocus sequence analysis (MLSA). A high level of recombination was found, associated with strong diversification and a reticulate evolutionary pattern of Arthrobacter sensu lato. We also collected a total of 31 cold-adapted Arthrobacter sensu lato strains from two cold glaciers located in northwest China and two temperate glaciers in southwest China, and evaluated their diversity and population structure by MLSA. The glacier strains displayed high diversity, but rates of recombination among the four glacier groups were quite low, indicating that barriers to homologous recombination formed in the past among the populations on different glaciers. Our findings indicate that historical glaciation events shaped the contemporary distributions, taxonomic relationships, and phylogeographic patterns of Arthrobacter sensu lato species on glaciers.  相似文献   

13.
Among fossil chelonians from the Tertiary of Western Europe, freshwater Testudinoidea (sensu Hirayama, 1985, Gaffney et Meylan, 1988) are abundant, and more particularly the “Palaeochelys sensu lato—Mauremys” group. This group has never been studied as a whole. Taxa of this group were before referred to extinct genera such as Ocadia, Clemmys, Emys or to the fossil genera Palaeochelys, Borkenia and Palaeoemys. These taxa are redefined, new taxa are described and a hypothesis of phylogenetic relationships is given.  相似文献   

14.
The ultrastructure of spermiogenesis and spermatozoa is examinedfor the first time in the heterogastropod family Mathildidae(Mathilda brevicula Bavay and Mathilda sp.). Mathildid spermatozoaexhibit the following features: (1) an ovoid acrosomal vesicleshowing curved dense layers basally and underlain by a thincurved plate; (2) a solid, rod-shaped nucleus showing a shallowbasal invagination (nucleus helically keeled in Mathilda sp.);(3) a midpiece composed of a 9+2 axoneme, 9 thick and periodicallybanded coarse fibres (associated with the axonemal doublets)and a continuous mitochondrial derivative; (5) glyco-gen piececomposed of the axoneme surrounded by dense granules; (6) andend piece (paddle-shaped terminally). Results of the study demonstratethat mathildids share the same key sperm and spermi-ogenic featuresobserved in the Architectonicidae. The monophyly of the Architectonicoidea,established by previous authors on anatomical grounds, is thereforeconfirmed using sperm morphology. Spermatozoa of the two mathildidsinvestigated lack the periodically banded midpiece structuresseen in investigated species of Architectonica (A. pcrspectiva(Linnaeus), A. perdix (Hinds)), Heliacus (H. (Heliacus) variegatus(Gmelin)) and Pseudotorinia (P. laseronorum (Iredale)) therebyresembling most closely the spermatozoaof Philippia lutea (Lamarck)and Psilaxis oxytropis (A. Adams) which also lack suchbandedstructures. Given the widely accepted primitive status of theMathildidae within the Architectonicoidea, the genera Philippiaand Psilaxis may prove to be relatively basal rather than advancedgenera within the Architectonicidae. Thi: view needs to be testedby examination of sperm morphology in other genera of the Architectonicidaeand also the basal mathildid genus Tuba sensu lato (= Gegania+ Tubena). Such information will be vital in any future cladisticstudy of the Architectonicoidea. (Received 16 June 1994; accepted 6 February 1995)  相似文献   

15.
An in-depth understanding of the biology of animals will requirethe generation of genomics resources from organisms from allphyla in the metazoan phylogenetic tree. Such resources willideally include complete genome sequences and comprehensiveEST (expressed sequence tag) datasets for each species of interest.Of particular interest in this regard are animals in the earlydiverging non-bilaterian phyla Porifera, Placozoa, Cnidaria,and Ctenophora. Publications describing the results from theuse of genomics approaches in these phyla have only recentlybegun to appear (Kortschak et al., 2003; Yang et al., 2003;Steele et al., 2004). Issues to be considered here include choosingthe basal metazoan species to examine with genomics approaches,the relative advantages and disadvantages of genome sequencingversus EST projects, and the resources and infrastructure requiredto carry out such projects successfully.  相似文献   

16.
Diurnal patterns of CO2 exchange and fluctuations of tissuemalic acid concentrations were investigated in three speciesof Commelinaceae: Callisia fragrans and Tripogandra multiflorafrom Jamaica, and Tradescantia brevifolia from southern Texas.Very low levels of CAM gas exchange were induced by droughtstress in C. fragrans and T. multiflora. In addition, past indicationsof CAM-cycling in the two Jamaican species were confirmed indrought-stressed plants; however, only C. fragrans exhibitedCAM-cycling under well-watered conditions. CAM-cycling underdrought stress was also found in T. brevifolia. This constitutesthe first report of CAM (sensu lato) in the genus Tradescantia.The importance of low-level CAM in these three species is discussedas a potential adaptation to drought.Copyright 1994, 1999 AcademicPress Callisia fragrans, Tradescantia brevifolia, Tripogandra multiflora, Commelinaceae, CO2 exchange, Crassulacean acid metabolism, CAM-cycling, CAM-idling, drought stress, malic acid fluctuations  相似文献   

17.
Mole-rats from Karonga, Malawi, the type locality ofCryptomys hottentotus whytei, and a single female mole-rat from the Malawian Nyika Plateau exhibit a karyotype 2n = 4 6 chromosomes, wit h 1 5 metacentr ic an d 8 acrocentr ic chromosome, s ie NF (female) = 76. This trait, together with several morphological features and a previously published genetic analysis (Ingramet al. 2004), identifies this species as a good species, unrelated toCryptomys hottentotus of South Africa, which belongs to the Zambezian clade of the genusCryptomys sensu lato (cf Ingramet al. 2004) and should be therefore called Whyte’s mole-rat,Cryptomys whytei. Available data on ecology and reproductive biology sugges t simila r characteristic s a s i n othe r mole-rat s o f th e genu.s Unexpecte d findin g of lar ge complicat ed undergroun d burro w system s contrasted, howev,e r wi th ve ry f ew abo ve grou nd moun.d s  相似文献   

18.

Background and Aims

Until recently, there was no consensus regarding the phylogenetic relationships of the Neotropical orchid genera Scuticaria Lindl. and Dichaea Lindl. However, recent evidence derived from both gross morphological and molecular studies supports the inclusion of Scuticaria and Dichaea in sub-tribes Maxillariinae and Zygopetalinae, respectively. The present paper describes the labellar micromorphology of both genera and seeks to establish whether labellar characters support the assignment of Scuticaria and Dichaea to these sub-tribes.

Methods

The labella of four species of Scuticaria and 14 species of Dichaea were examined using light microscopy and scanning electron microscopy, and their micromorphology was compared with that of representative species of Maxillariinae sensu lato and Zygopetalinae (Huntleya clade).

Key Results and Conclusions

In most specimens of Scuticaria examined, the papillose labella bear uniseriate, multicellular, unbranched trichomes. However, in S. steelii (Lindl.) Lindl., branched hairs may also be present and some trichomes may fragment and form pseudopollen. Multicellular, leaf-like scales were also present in one species of Scuticaria. Similar, unbranched hairs are present in certain species of Maxillaria Ruiz & Pav. (Maxillariinae sensu stricto) and Chaubardia Rchb.f. (Huntleya clade). As yet, moniliform, pseudopollen-forming hairs have not been observed for Zygopetalinae, but their presence in Scuticaria steelii, Maxillaria and Heterotaxis Lindl. supports the placing of Scuticaria in Maxillariinae. As other genera are sampled, the presence of branched hairs, hitherto unknown for Maxillariinae sensu lato, may prove to be a useful character in taxonomy and phylogenetic studies. Euglossophily occurs in Dichaea, as well as Chondrorhyncha Lindl. and Pescatorea Rchb.f. (Huntleya clade), and all three genera tend to lack distinctive labellar features. Instead, lip micromorphology is relatively simple and glabrous or papillose. However, two of the Dichaea species examined bear unicellular, labellar trichomes very similar to those found in Bifrenaria Lindl. (pollinated by both euglossine bees and Bombus spp.), and this feature may have arisen by convergence in response to similar pollination pressures.Key words: Bifrenaria, Bifrenaria clade, Chaubardia, Chondrorhyncha, Dichaea, Dichaeinae, Heterotaxis, Huntleya clade, Huntleyinae, labellum, Maxillaria, Maxillariinae, papillae, Pescatorea, scales, Scuticaria, trichomes, Zygopetalinae  相似文献   

19.
20.
A mannose-specific lectin was isolated from leaves of Neoregeliaflandria, an ornamental plant that belongs to Bromeliaceae,a family of monocotyledons. The amino acid composition and molecularmass of the lectin were similar to those of mannose-specificlectins from other monocotyledons. However, in a test to examinethe inhibition of hemagglutination, it became apparent thatthe isolated lectin recognized D-glucose and N-acetyl D-glucosaminein addition to D-mannose, unlike mannose-specific lectins fromthe monocotyledons that have been reported to date. (Received May 17, 1996; Accepted August 19, 1996)  相似文献   

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