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51.
52.
以桂林地区产出的大量Sinospongophyllum的个体发育资料为基础,结合我国描述的Sinospongophyllum和Tabulophyllum以及国外已描述的一些有代表性的种作系统发育分析,用分校分析方法,判别这两个属的亲疏关系,认为Sinospongophyllum和Tabulophyllum并非同义属。同时,对桂林地区大量产出的Sinospongophyllumcrassiseptatumsp.nov.居群内变异作了较为详细的研究,并讨论了引起变异的可能原因。 相似文献
53.
Ho Ju-Shey 《International journal for parasitology》1994,24(8):1293-1300
Six of the 10 recognised families of the order Cyclopoida are parasitic, with 4 of them occurring on marine invertebrates and the remaining 2 on freshwater gastropods and fishes, respectively. A cladistic analysis of the 10 families indicates that evolution of parasitism occurred twice in the history of the cyclopoids. The first attempt was made by the marine epibenthic ancestors seeking food and shelter in sessile tunicates — the ascidians. This event led to the evolution of 2 ascidicolous families: Archinotodelphyidae and Notodelphyidae. The descendant of this lineage had also invaded the mantle cavity of marine bivalve molluscs, eventually leading to the evolution of the Mantridae. The second attempt for the parasitic mode of life was launched by the ancestor which was the sister group of the ancestral cyclopoids — the most successful family of freshwater copepods. This ancestral stock, while living in the coastal zone, split into 2 groups: one group stayed behind in the ocean and colonised again the ascidians; the other groups invaded freshwater and evolved into the fish-parasitising Lernaeidae and the gastropod-parasitising Ozmanidae. 相似文献
54.
On the marine sister groups of the freshwater crabs (Crustacea: Decapoda: Brachyura) 总被引:1,自引:0,他引:1
R. von Sternberg N. Cumberlidge G. Rodriguez 《Journal of Zoological Systematics and Evolutionary Research》1999,37(1):19-38
Freshwater crab sister group relationships with marine eubrachyuran families were investigated. A morphology-based cladistic analysis was conducted on representatives of the freshwater crab families Deckeniidae, Gecarcinucidae, Parathelphusidae, Potamidae, Potamonautidae, Pseudothelphusidae, and Trichodactylidae using a disparate assemblage of marine heterotreme and thoracotreme brachyurans as possible sister groups. The monophyly of the freshwater crabs sensu lato is falsified. The family Trichodactylidae and the marine portunid subfamily Carcininae form basal groups within the superfamily Portunoidea. The monophyly of the Pseudothelphusidae and the Paleotropical freshwater crab families is supported, and this clade is the sister group of the Thoracotremata (Gecarcinidae, Grapsidae s.l., and Ocypodoidea). The origin, groundplan, and diversification of freshwater crabs are discussed in the context of previously published scenarios of their evolution. 相似文献
55.
Mark A. Carine Christopher J. Humphries I. Rosana Guma J. Alfredo Reyes-Betancort Arnoldo Santos Guerra 《Journal of Biogeography》2009,36(4):593-611
Aim Areas of endemism are the fundamental units of cladistic biogeographical analysis but there is no consensus on the most appropriate method for their delimitation. In this paper, the relative performance of a number of algorithmic approaches for the delimitation of areas of endemism is investigated within the context of the Canary Islands flora, and areas of endemism within the Canary Islands archipelago are defined. Location The Canary Islands. Methods A data matrix comprising the distributions of 609 endemic spermatophyte taxa (c. 90% of the endemic flora) scored on a 10 × 10 km UTM grid was analysed using: (1) UPGMA (unweighted pair group method with arithmetic mean) clustering of Jaccard and Kulczynski similarity coefficient matrices, (2) parsimony analysis of endemicity (PAE), and (3) the program ndm (eNDeMism). The performance of each method was then determined by the extent to which the resulting areas of endemism met three criteria: (1) possession of two or more strict endemic taxa, (2) diagnosability, and (3) geographical contiguity. Results Each of the four methods resulted in substantially different sets of areas. ndm analysis resolved 17 areas of endemism consistent with all three criteria, and collectively these accounted for 59% of all cells. In the hierarchical analyses none of the methods recovered more than eight areas of endemism, and the total coverage of cells ranged from 13% to 33% when the results were confined to intra‐island areas of endemism. Main conclusions ndm outperforms hierarchical clustering methods in terms of both the number of intra‐island areas of endemism delimited that meet the three evaluation criteria and the total coverage of those areas. ndm may also be considered preferable because it is non‐hierarchical, incorporates spatial information into the delimitation of areas, and permits overlap between areas of endemism where there is evidence to support it. The results support the use of ndm as the most appropriate method currently available for the delimitation of areas of endemism. The areas of endemism identified by the ndm analysis are discussed. 相似文献
56.
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58.
石蒜属植物分支系统学分析 总被引:10,自引:0,他引:10
基于37个形态学、解剖学、孢粉学和细胞学性状及解剖学性状之外的28个形态学、孢粉学和细胞学性状,分别对石蒜属进行分支系统学分析,试图建立石蒜属种间的系统发育关系。利用PAUP*软件分别构建了最大简约树(MP),所得树的拓扑结构是一致的。同时,基于解剖学9个性状,对石蒜、换锦花、忽地笑、江苏石蒜、长筒石蒜、乳白石蒜、夏水仙、红兰石蒜、安徽石蒜、短蕊石蒜、中国石蒜11个种进行系统发育树构建,其结果也是支持上述系统发育树的。系统发育树结构结果表明,石蒜属16种明显聚为两大类:石蒜、玫瑰石蒜、稻草石蒜和江苏石蒜;广西石蒜、红兰石蒜、换锦花、香石蒜、夏水仙、长筒石蒜、安徽石蒜、中国石蒜、忽地笑、乳白石蒜、短蕊石蒜和陕西石蒜。除换锦花、红兰石蒜及江苏石蒜系统发育位置不同之外,大类群的划分与RAPD指纹图谱基本一致。类群一均属于石蒜亚属(Lycoris亚属)。类群二又可以聚为两小类:广西石蒜、红兰石蒜、换锦花、香石蒜、夏水仙归为一类;长筒石蒜、安徽石蒜、中国石蒜、忽地笑、乳白石蒜、短蕊石蒜和陕西石蒜归为一类。前一子类群除广西石蒜外,都属于整齐花亚属(Symman thus亚属)。后一子类群除长筒石蒜与安徽石蒜外,均属于石蒜亚属(Lycoris亚属)。因此,花冠整齐与否是一个重要的分类特征,但作为石蒜属植物亚属的划分依据,没有得到本研究支持。而在本文中,雄蕊与花被片的位置关系可以作为大分类群划分依据,能否依此来对石蒜属植物亚属进行划分,仍需探讨。另外研究表明叶微形态特征在研究种间亲缘关系时,具有一定的作用。而在种间亲缘关系鉴定时,出叶期不应成为重要的依据。同时研究还表明中国石蒜与忽地笑具有非常近的亲缘关系,与形态学研究一致。 相似文献
59.
P. J. Habgood 《Human Evolution》1989,4(4):241-252
Cladistic analyses for the study of hominid evolution become very common during the last two decades, but little attention
has been given to the appropriateness of the approach to studies being undertaken. This paper discusses how cladistic analyses
have been used in studies of late Middle and Upper Pleicostocene hominids without due consideration of the problems inherent
within the approach. It is concluded that in studies of the origin of anatomicaly modern humans a strict cladistic approach
is inappropriate because it takes too narrow a view (presence/absence) of morphology, and in doing so does not allow for morphological
variation. A phenetic approach which is interested in overall morphological similarity based on many characters and attempts
to sample the total morphological variability evident within a sample would seem a more appropriate approach in such studies. 相似文献
60.
Thereza de A. Garbelotto Luiz A. Campos Jocelia Grazia 《Zoological Journal of the Linnean Society》2013,168(3):452-472
Alitocoris Sailer, 1950, consists of four valid species described from Central America. In a recent cladistic analysis of Ochlerini, the genus was considered paraphyletic in the Herrichella Distant, 1911, group of taxa. The present study provides a cladistic analysis of the Herrichella clade, using 88 morphological characters and 40 taxa representing 21 genera of Ochlerini, including all known species of Alitocoris plus 16 new species. Outgroups included Eritrachys bituberculata Ruckes, 1959, Phereclus pluto Stål, 1862, and Adoxoplatys comis Breddin, 1903, with the last used for rooting. The cladistic analysis was conducted using TNT under heuristic searches and implied weighting of characters; 11 K‐values calculated for an average character fit ranged from 50 to 90% of a perfectly hierarchical character. The results corroborated the paraphyly of Alitocoris, calling for changes in the classification of the genus with the proposition of three new genera for two, three, and ten species, respectively, that will be described elsewhere. Alitocoris is redescribed and a key for the species is presented. Alitocoris brunneus, Alitocoris maculosus, and Alitocoris parvus are removed from the genus, and the new species Alitocoris grandis sp. nov. , Alitocoris lateralis sp. nov. , and Alitocoris ornatus sp. nov. are described. © 2013 The Linnean Society of London 相似文献