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1.
The phylogeny of the New Zealand hepialid moths was estimated from a cladistic analysis of sixty‐three morphological characters, from all life cycle stages. One hundred and sixteen maximum parsimony trees were produced. The phylogenetic reconstruction indicated that the currently recognized generic concepts, and the four informal lineages hypothesized in a previous morphological taxonomic revision, were monophyletic. The relationships of species within genus Wiseana were not fully resolved. Analysis of a data set of thirty‐nine adult male characters from the New Zealand taxa and the Australian genera Jeana, Oxycanus and Trictena supported the monophyly of the New Zealand ‘Oxycanus’ s.s lineage.  相似文献   

2.
Four new species of the genus Porphyra (Bangiales, Rhodophyta) from the New Zealand region are described: P. cinnamomea W.A. Nelson, P. coleana W.A. Nelson, P. rakiura W.A. Nelson and P. virididentata W.A. Nelson. These species are monostromatic, monoecious, and grow in the intertidal zone, predominantly on rock substrata. They can be distinguished from each other by traditional characters including morphology (particularly the microscopic arrangement of cells along the thallus margin, thallus shape, size and colour), geographical, ecological and seasonal distribution patterns, and chromosome numbers (P. cinnamonea n = 3, P. coleana n = 4, P. rakiura n = 2, P. virididentata n = 3). These four species can be distinguished by a unique nucleotide sequence at the 18S rDNA locus: they can be separated on the basis of a subset of approximately 500 bp of 18S rDNA sequence data downstream of primer G06, corresponding to variable region V9. This constitutes an important taxonomic character. These four species are known currently solely from the New Zealand region.  相似文献   

3.
RICE, E. L., 1989. A statistical morphological analysis and taxonomic revision of the genus Xiphophora (Fucaceae). Xiphophora is a brown seaweed endemic to the cool temperature rocky shores of Australia and New Zealand. The two species, X. chondrophylla and X. gladiata have previously been separated by morphological criteria. However, the differences betweeen them in these characters were largely size-related, resulting in taxonomic confusion. In particular, the presence of X. gladiata in New Zealand has been disputed. In this study, a series of discriminant function analyses were performed, based on a suite of morphological characters collected from each species throughout a major portion of their geographic ranges. The results show conclusively that the present taxonomy of Xiphophora is untenable. This genus is composed of two species, but these are distributed latitudinally (either side of the 40oS parallel). Each species contains two allopatric subspecies; one in Australia and the other in New Zealand. A formal taxonomic revision of the genus is presented.  相似文献   

4.
Since 1992, as part of a study to circumscribe the genus Porphyra in New Zealand, an extensive culture programme has been developed at the Museum of New Zealand Te Papa Tongarewa. This collection currently houses more than 800 cultures and 150strains. We currently recognise at least 20 species in New Zealand, most of which are undescribed. Close observation of reproduction and the development of conchocelis-phase filaments grown in the laboratory, under controlled conditions of temperature, irradiance and photoperiod, has enabled the recognition of characters that can assist in species separation. The comparative taxonomic value of a range of such characters is discussed, including reporting a novel reproductive mode. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

5.
6.
The family Mugilidae comprises mainly coastal marine species that are widely distributed in all tropical, subtropical and temperate seas. Mugilid species are generally considered to be ecologically important and they are a major food resource for human populations in certain parts of the world. The taxonomy and systematics of the Mugilidae are still much debated and based primarily on morphological characters. In this study, we provide the first comprehensive molecular systematic account of the Mugilidae using phylogenetic analyses of nucleotide sequence variation at three mitochondrial loci (16S rRNA, cytochrome oxidase I, and cytochrome b) for 257 individuals from 55 currently recognized species. The study covers all 20 mugilid genera currently recognized as being valid. The family comprises seven major lineages that radiated early on from the ancestor to all current forms. All genera that were represented by two species or more, except Cestraeus, turned out to be paraphyletic or polyphyletic. Thus, the present phylogenetic results generally disagree with the current taxonomy at the genus level and imply that the anatomical characters used for the systematics of the Mugilidae may be poorly informative phylogenetically. The present results should provide a sound basis for a taxonomic revision of the mugilid genera. A proportion of the species with large distribution ranges (including Moolgarda seheli, Mugil cephalus and M. curema) appear to consist of cryptic species, thus warranting further taxonomic and genetic work at the infra-generic level.  相似文献   

7.
8.
The model species Antirrhinum majus (the garden snapdragon) has over 20 close wild relatives that are morphologically diverse and adapted to different Mediterranean environments. Hybrids between Antirrhinum species have been used successfully to identify genes underlying their phenotypic differences, and to infer how selection acts on them. To better understand the genetic basis for this diversity, we have examined the evolutionary relationships between Antirrhinum species and how these relate to geography and patterns of phenotypic variation in the genus as a whole. Large population samples and both plastid and multilocus nuclear genotypes resolved the relationships between many species and provided some support for the traditional taxonomic division of the genus into morphological subsections. Morphometric analysis of plants grown in controlled conditions supported the phenotypic distinction of the two largest subsections, and the involvement of multiple underlying genes. Incongruence between nuclear and plastid genotypes further suggested that several species have arisen after hybridization between subsections, and that some species continue to hybridize. However, all potential hybrids appear to have retained a phenotype similar to one of their ancestors, suggesting that ancestral combinations of characters are maintained by selection at many different loci.  相似文献   

9.
Skinks of the genus Sphenomorphus are the most diverse clade of squamates in the Philippine Archipelago. Morphological examination of these species has defined six phenotypic groups that are commonly used in characterizations of taxonomic hypotheses. We used a molecular phylogeny based on four mitochondrial and two nuclear genes to assess the group's biogeographical history in the archipelago and examine the phylogenetic validity of the currently recognized Philippine species groups. We re‐examined traditional characters used to define species groups and used multivariate statistics to quantitatively evaluate group structure in morphometric space. Clustering analyses of phenotypic similarity indicate that some (but not all) members of previously defined species groups are phenotypically most similar to other members of the same group. However, when species group membership was mapped on our partitioned Bayesian phylogenetic hypothesis, only one species group corresponds to a clade; all other species group arrangements are strongly rejected by our phylogeny. Our results demonstrate that (1) previously recognized species group relationships were misled by phenotypic convergence; (2) Sphenomorphus is widely paraphyletic; and (3) multiple lineages have independently invaded the Philippines. Based on this new perspective on the phylogenetic relationships of Philippine Sphenomorphus, we revise the archipelago's diverse assemblage of species at the generic level, and resurrect and/or expand four previously recognized genera, and describe two new genera to accommodate the diversity of Philippine skinks of the Sphenomorphus group. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 163 , 1217–1243.  相似文献   

10.
Basispora is recognised as a new genus of the Ralfsiaceae (Phaeophyceae), distinguished from other members of this family by the terminal unilocular sporangia arising on long stalks from near the base of the simple, often assurgent, laterally free erect filaments. The type species Basispora africana is described; it is widely distributed along the West African coast. Two other taxa from New Zealand, formerly included in Hapalospongidium, are transferred to this new genus, necessitating the new combinations Basispora saxigena and B. durvilleae. These three species are separated on the structure of the vegetative thallus, dimensions, shape of the sporangial stalk and on the type of substrate on which they grow.  相似文献   

11.
Mirabilis, a primarily American genus of 50?C60 species almost restricted to the New World, is the most diverse within Nyctaginaceae. It not only has the greatest number of species, but also many life forms, with annual herbaceous, suffrutescent and shrubby species and with prostrate, decumbent to erect stems that are sometimes clambering. Stem anatomy has been studied only for M. jalapa, and its characteristics extrapolated to the entire genus. In this study we evaluated the taxonomic significance of stem anatomical characters from 24 species of Mirabilis, as well as their potential relation to habit evolution. Qualitative and quantitative characters of transverse and longitudinal sections were evaluated using light and scanning electron microscopy. Stem anatomy varies in several features. The phloem is arranged in short tangential spreading bands or in large tangential bands forming semi-complete rings; the conjunctive tissue is fibrous, with thin-walled sclereids and fibres, or parenchymatous; the vessels are solitary or grouped in radial multiples or clusters; the xylem fibres are very thin-walled or thin- to thick-walled with simple to minutely bordered pits; most species are raylessness; the pith has parenchyma or thin-walled sclereids or brachysclereids. The distribution of anatomical characters in Mirabilis does not correspond with the current infrageneric classification. We suggest that some stem anatomical characters are correlated with habit and that the vascular cylinder and pith characters are related to an increase in mechanical strength. This study provides new information and novel characters about the stem anatomy not only of Mirabilis, but of the family.  相似文献   

12.
13.
MIDDLETON, D. J., A systematic survey of leaf and stem anatomical characters in the genus Gaultheria and related genera (Ericaceae). Leaf and stem anatomical characters of 123 species within the Gaultheria group of genera of the tribe Andromedeae are surveyed. A number of characters show considerable variation within a species which limits their taxonomic use. Other characters such as marginal sclerenchyma and, to a lesser extent, the hypodermis, the presence of adaxial stomata, the presence of free fibres and the pith type were of more taxonomic interest. These characters are discussed in relation to the generic and infrageneric classification of the group.  相似文献   

14.
The New Zealand Pipit Anthus novaeseelandiae occurs as a single species in Europe (as Richard's Pipit), Asia, Africa, New Guinea, Australia and New Zealand. In the New Zealand region, subspecific status has been accorded to allopatric populations on the mainland (A. n. novaeseelandiae) , on the Auckland and Campbell Islands (A. n. aucklandicus) , on the Antipodes Islands (A. n. steindachneri) and on the Chatham Islands (A. n. chathamensis) . Analyses of 23 allozyme loci and morphometric variation of populations on mainland New Zealand and on the Auckland, Campbell, Antipodes and Chatham Islands showed an appreciable and significant divergence between mainland and island populations. The magnitude of the allozyme difference is sufficient to suggest full species designation for the island birds, a conclusion supported by morphometric analyses and in sharp contrast to current taxonomy. However, formal taxonomic change will not be undertaken until the two New Zealand groups have been compared with more distant populations of this wideranging genus. The cryptic variation found in this species has conservation management implications for the small offshore populations.  相似文献   

15.
对中国柱衣属Pilophorus进行了系统的分类学研究。通过标本采集发现了6个种,包含过去报道的4个种:P. acicularis,P. cereolus,P. clavatus和P. curtulus,以及两个作者近期发表的种:P. fruticosus和P. yunnanensis。对这6个种进行了形态学,解剖学以及化学特征的描述,并且提供了中国柱衣属的检索表和形态特征。  相似文献   

16.
The current taxonomic treatment of the genusPipturus (Urticaceae) in the Hawaiian Islands is evaluated in terms of anatomical and cytological criteria. This work revealed no distinct anatomical discontinuities between ten of the 13 species currently recognized. All taxa were found to be diploid with the chromosome complement of 14 pairs. The conclusion is advanced that the ingress of this genus to Hawaii probably involved a single introductory stock and that the current 13 species may be a large complex of intergrading races involving perhaps only two species.  相似文献   

17.
Coralline red algae from the New Zealand region were investigated in a study focused on documenting regional diversity. We present a multi‐gene analysis using sequence data obtained for four genes (nSSU, psaA, psbA, rbcL) from 68 samples. The study revealed cryptic diversity at both genus and species levels, confirming and providing further evidence of problems with current taxonomic concepts in the Corallinophycidae. In addition, a new genus Corallinapetra novaezelandiae gen. et sp. nov. is erected for material from northern New Zealand. Corallinapetra is excluded from all currently recognized families and orders within the Corallinophycidae and thus represents a previously unrecognized lineage within this subclass. We discuss rank in the Corallinophycidae and propose the order Hapalidiales.  相似文献   

18.
The round-eared sengis or elephant-shrews (genus Macroscelides) exhibit striking pelage variation throughout their ranges. Over ten taxonomic names have been proposed to describe this variation, but currently only two taxa are recognized (M. proboscideus proboscideus and M. p. flavicaudatus). Here, we review the taxonomic history of Macroscelides, and we use data on the geographic distribution, morphology, and mitochondrial DNA sequence to evaluate the current taxonomy. Our data support only two taxa that correspond to the currently recognized subspecies M. p. proboscideus and M. p. flavicaudatus. Mitochondrial haplotypes of these two taxa are reciprocally monophyletic with over 13% uncorrected sequence divergence between them. PCA analysis of 14 morphological characters (mostly cranial) grouped the two taxa into non-overlapping clusters, and body mass alone is a relatively reliable distinguishing character throughout much of Macroscelides range. Although fieldworkers were unable to find sympatric populations, the two taxa were found within 50 km of each other, and genetic analysis showed no evidence of gene flow. Based upon corroborating genetic data, morphological data, near sympatry with no evidence of gene flow, and differences in habitat use, we elevate these two forms to full species.  相似文献   

19.
Labyrinthulids and thraustochytrids are unicellular heterotrophs, formerly considered as fungi, but presently are recognized as members in the stramenopiles of the kingdom Protista sensu lato. We determined the 18S ribosomal RNA gene sequences of 14 strains from different species of the six genera and analyzed the molecular phylogenetic relationships. The results conflict with the current classification based on morphology, at the genus and species levels. These organisms are separated, based on signature sequences and unique inserted sequences, into two major groups, which were named the labyrinthulid phylogenetic group and the thraustochytrid phylogenetic group. Although these groupings are in disagreement with many conventional taxonomic characters, they correlated better with the sugar composition of the cell wall. Thus, the currently used taxonomic criteria need serious reconsideration.  相似文献   

20.
A numerical taxonomic analysis was performed on 79 phenotypic characters of 147 imperfect yeast species currently assigned to the genus Candida. The characters used were drawn from two monographs on yeast taxonomy. The analysis revealed 10 clusters of three or more species that were similar at the level of 75% or more, and seven clusters containing only one or two species. None of the 10 major clusters contained exclusively species that were traditionally assigned to the genus Torulopsis, while the 12 Candida species of basidiomycetous affinity fell into three clusters with only one species of ascomycetous affinity included. Statistical determination of the five most important differential characters for each cluster failed to show the property of pseudomycelium/mycelium formation as significant for any cluster. The study provides no evidence to support a distinction between taxa that were formerly divided between the genera Candida and Torulopsis and supports previous proposals that these genera should be fused.  相似文献   

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