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谢树莲 《山西大学学报(自然科学版)》2007,30(2):245-250
以串珠藻目的16个分类单位加上外类群作为研究对象,选取18个性状作为研究基础,得到18×17的数值矩阵,以分支分类学的方法对串珠藻目的系统发育过程进行分析.采用4种方法进行分支分析,其中以最大同步法的运算结果最为合理,分支图最大步长为269,最小步长为35,实际步长为47,简约系数为0.0513.在串珠藻目中,以红索藻科最为原始,它向两个方向演化,其中一大支随着受精丝的明显膨大,演化出串珠藻科;另一大支则有更多的形态特征发生变化,配子体中出现假薄壁组织,中轴节处产生有定数的分枝,出现发达的外皮层,精子囊以精子囊群的方式成块状或带状出现,果孢子体生于外皮层内部,演化出鱼子菜科和裸管藻科.在串珠藻科中,以串珠藻属的串珠藻组较为原始,而假枝藻属和托氏藻属则较为进化. 相似文献
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本研究中,我们对响叶杨的叶绿体基因组进行测序和组装,并将其与杨属其他11个叶绿体基因组进行比较分析.结果表明,响叶杨叶绿体基因组全长158,591bp,其中两个反向重复序列区(IR)长度均为27,667bp,长单拷贝序列区(LSC)和短单拷贝序列区(SSC)长度分别为84,634和18,623bp.通过对杨属12个物种的叶绿体基因组进行比较,只发现了6个相对较大的插入缺失,因此整体而言,杨属的叶绿体基因组结构是高度保守的.系统发育分析结果显示,杨属中12个物种组成了3个具有高支持率的进化支,响叶杨与其他白杨组物种聚为一支,并且与银白杨的亲缘关系最近.本研究基于叶绿体基因组数据揭示了杨属的进化历史,将有助于进一步开展杨属植物基于叶绿体DNA序列数据的群体遗传学及其他分子生态学研究. 相似文献
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李先超 《北京联合大学学报(自然科学版)》2012,26(3):41-45
通过制备野生鼠尾藻基因组DNA,用同源克隆技术获得鼠尾藻的SSU rDNA序列。该序列长度为1 784 bp,A、G、T、C 4种碱基的含量分别为24.66%、27.75%、26.35%和21.24%,序列已提交至GenBank,登录号为JN604979。选用GenBank数据库中已有的褐藻SSU rDNA序列构建系统发生树,结果显示:鼠尾藻与半叶马尾藻,铜藻以及Sargassum macrocarpum聚为一支,并且与半叶马尾藻的亲缘关系最近。 相似文献
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《Journal of Natural History》2012,46(16):1887-1986
Fifty-one species are recognized in the genus Paurocephala, with an additional 14 species which remain unnamed. Thirty-five species are described as new, and five species are synonymized: P. pumilae and P. zhejiangensis with P. chonchaiensis, P. debregeasiae with P. sauteri, and P. guangxiensis and P. tremae with P. trematos. Two varieties, P. psylloptera maculipennis and P. psylloptera setifera, are raised to species level. P. bifasciata is reinstated from former synonymy with P. chonchaiensis, and Anomoterga kleinhofiae is transferred back to Paurocephala. Lectotypes are designated for P. brevicephala, P. chonchaiensis, P. psylloptera, P. sauteri, P. setifera and P. wilderi. The four New World species of Paurocephala are not considered to be congeneric with the Old World species and will be transferred to Diclidophlebia. Two South African species, P. bicarinata and P. hottentotti, are removed from Paurocephala and have to be accommodated in a new genus in the Diaphorininae. Thus Paurocephala is an Old World genus with nine Afrotropical and 42 Indo-Australian described species. Keys for the identification of adults and fifth instar larvae are provided. All 51 named species are diagnosed and illustrated, and information is given on distribution and host plants. Based on two cladistic analyses, one using adult characters only, and one using both adult and larval characters, four monophyletic species groups are recognized. In both analyses a basal group of 10 species, the brevicephala -group, forms the sister group to all other Paurocephala spp. The Afrotropical species are monophyletic and, together with one Oriental species constitute the gossypii group. In the analysis with adult characters only, the gossypii -group is the sister taxon of the kleinhofiae -group and, both together, are the sister group of the psylloptera -group, the largest species group with 27 species. In the analysis of adult and larval characters, the relationships between the last three species groups are not resolved. The result of the phylogenetic analysis confirms the synonymy of the subgenus Thoracocorna with Paurocephala. Known host plants of Paurocephala spp. belong to the Malviflorae with the exception of the Afrotropical P. insolita which develops on Theiflorae (Theales, Clusiaceae). The brevicephala -, kleinhofiae - and gossypii -groups are associated with hosts of the order Malvales (Malvaceae and Sterculiaceae), whereas the psylloptera -group is with Urticales (Urticaceae, Moraceae and Ulmaceae). 相似文献
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《Journal of Natural History》2012,46(18):2139-2183
The xystodesmid millipede genus Parafontaria Verhoeff, 1936 is revised in the light of the geographic variation found in the genital morphology of both sexes. The following 11 species, including one new species, are recognized as valid: P. erythrosoma (Takakuwa, 1942), P. ishiii Shinohara, 1986, P. doenitzi (Karsch, 1880), P. laminata (Attems, 1909), P. crenata Shinohara, 1986, P. longa Shinohara, 1986, P. tokaiensis n. sp., P. shiraiwaensis Shinohara, 1986, P. falcifera (Verhoeff, 1936), P. spathulata (Miyosi, 1951) and P. takakuwai (Shinohara, 1957). Parafontaria tonominea (Attems, 1899) can be recognized as a species complex and is operationally defined as a species. The systematic status of P. terminalis (Takakuwa, 1942) is uncertain. The following new synonymies are proposed: Fontaria (Parafontaria) armigera Verhoeff, 1936 (currently P. laminata armigera (Verhoeff, 1936)), F. (P.) kuhlgatzi Verhoeff, 1937 (currently P. kuhlgatzi (Verhoeff, 1937)) and P. echizenensis Shinohara, 1986 with P. laminata; F. coarctata circula Attems, 1901 (currently P. circula (Attems, 1901)), F. coarctata acutidens Attems, 1909 (currently P. acutidens (Attems, 1909)), F. (Japonaria) spiraligera Verhoeff, 1937 (currently P. spiraligera (Verhoeff, 1937)), F. (J.) marmorata Verhoeff, 1937 (currently P. marmorata (Verhoeff, 1937)), Japonaria longispinosa longispinosa Miyosi, 1951 (currently P. longispinosa longispinosa (Miyosi, 1951)), J. longispinosa falcata Miyosi, 1951 (currently P. longispinosa falcata (Miyosi, 1951)), J. egregia Haga, 1968 (currently P. egregia (Haga, 1968)) with P. tonominea. A cladistic analysis based on 15 morphological characters was performed for all species except P. terminalis. The strict and majority rule (50%) consensus trees identified three and five clades, respectively, within the genus. 相似文献
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《Journal of Natural History》2012,46(10):1517-1563
A total of 53 Amiota (s. str.) species (75% of the world total) from Asia and Europe, including 10 new species, kamui, kimurai and planata from Japan, and aristata, cuii, macai, magniflava, nuerhachii, spinata and watabei from China, are reviewed with designation of two new synonymies and phylogenetic analysis. Based upon the result of cladistic analysis with 31 adult male morphological characters, the following conclusions are deduced: (1) The subgenus Amiota is monophyletic, so far as the Asian and European forms are concerned. (2) Seven monophyletic groups are recognized within this subgenus. Two of them correspond to known species-groups, the apodemata and sinuata groups, and the remaining five are established as new species-groups, the nagatai, basdeni, taurusata, alboguttata and rufescens groups. A key to all the studied species from Asia and Europe is provided. 相似文献
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《Journal of Natural History》2012,46(2):169-173
The genus Renilla is an interesting taxon for phylogenetic studies, which includes six species endemic to America with an anphiamerican distribution Pacific-Atlantic Ocean). A cladistic analysis of Renilla Lamarck, 1816 using eight characters from external morphology produced one cladogram (length 14, CI = 0.92, RI = 0.87), and the characters were polarized using Echinoptilum macintoshii Hubrecht, 1885 as an outgroup. In the cladogram the following phylogenetic sequence results: ((R. koellikeri (R. muelleri, R. musaica)) (R. octodentata (R. reniformis, R. tentaculata))). 相似文献
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《Journal of Natural History》2012,46(6):913-953
Because of their ‘bizarre’ features, some echinoids can be considered laboratories in which to analyse the origin of extreme morphologies. The holasteroid family Urechinidae Duncan, 1889 is such a group. It is composed of 18 previously named living species in three genera: Urechinus A. Agassiz, 1879, Plexechinus A. Agassiz, 1898, and Pilematechinus A. Agassiz, 1904. With Stereopneustes, the most closely related living taxon, and the calymnid-plus-pourtalesiid clade as outgroups, a phylogenetic analysis on 35 binary characters is produced. We focus on two major aspects of morphology: test features (apical system, basicoronals, interambulacrum 5, test shape, ambulacra) and external appendages (pedicellariae, spines, sphaeridia). New data on plate architecture, morphology, and appendages are illustrated, and the position of the fossil, Chelonechinus, is discussed. We show that the Urechinidae is paraphyletic: the genus Plexechinus shares more recent common ancestry with the calymnids and pourtalesiids than with other urechinids. In order to retain the well-circumscribed clade, Pilematechinus A. Agassiz, 1904, the phylogenetic classification also recognizes two additional genera: Cystechinus A. Agassiz, 1879, and Antrechinus new genus. A key to the species is provided. The production of extreme morphologies, such as internal parental care, is explored by mapping test size, the occurrence of fascioles, and periproct position onto the phylogeny. By adding plates early in ontogeny, Pilematechinus develops radically different plate architectures from another genus of large forms, Cystechinus. In contrast, the latter gets large by exaggerating allometric trends seen in other holasteroids. Paedomorphosis and miniaturization have evolved independently in Antrechinus and some Plexechinus, but always by truncation of allometric trajectories. 相似文献