CAJ | 학술논문

在最新GenBank分子信息的汇集、分析基础上,利用小亚基单位核糖体RNA基因序列分别构建了最大简约树、距离树、最大似然树及贝叶斯树,对长期存在争议的游仆目纤毛虫的系统关系进行了探讨和修订.工作显示:1)游仆目不是1个单源发生系;2)盘头虫类从游仆目中较早分化出来,呈现与排毛类、寡毛类平行的进化关系;3)腹棘虫科内的腹棘虫和拟游仆虫体现了密切的亲缘关系;4)游仆虫科、舍太虫科、檐纤虫科在所有分子树中均表现了十分稳定的拓扑结构;5)游仆虫属内可以细分为7个亚类群;6)尾刺虫科在游仆目内分化较早,支持前人有关其在系统演化时序中处于原始阶段的论断.
재최신GenBank분자신식적회집、분석기출상,이용소아기단위핵당체RNA기인서렬분별구건료최대간약수、거리수、최대사연수급패협사수,대장기존재쟁의적유부목섬모충적계통관계진행료탐토화수정.공작현시:1)유부목불시1개단원발생계;2)반두충류종유부목중교조분화출래,정현여배모류、과모류평행적진화관계;3)복극충과내적복극충화의유부충체현료밀절적친연관계;4)유부충과、사태충과、첨섬충과재소유분자수중균표현료십분은정적탁복결구;5)유부충속내가이세분위7개아류군;6)미자충과재유부목내분화교조,지지전인유관기재계통연화시서중처우원시계단적론단.
Euplotids are among the best known and most readily recognized ciliate.s, which have been for a long time regarded as a monophyletic lineage. The order Euplotida contains several well-known taxa, e. g. Euplotes, Diophrys, Uronychia, Aspidisca, Gostrocirrhus, and Discocephalus etc. However, the phylogenetic relationships among them still remain confusing considering their evolutionary process and systematic positions of many groups due to the high diversity of the morphology and lacking molecular data. Phylogenetic trees were constructed in the present work using SS rRNA sequences obtained up-to-date in order to re-evaluate the systematic arrangement. Analyses using different tree construction methods revealed a consistent bmching pattern: 1) the typical euplodds belong to a paraphyletic group composed of 3 diverged dades (Uronychiidae, Euploddae-Certesiidae-Aspidisddae and Gastrocirrhida-e); 2) both clades formed by Euplotidae-Certesiidae-Aspidiscidae and Gastrocirrhidae were firmly supported with high bootstrap; 3) the family Discocephalidae forms a sister group to the large clade containing Euplotidae-Certesiidae-Aspidiscidae and Gastrocirrhidae, though its position remains ambiguous due to low supports; 4) Uronychiidae is clearly separated from the most other euplodds, which suggests the family should be positioned in the primordial phase of evolution, and 5) within Euplotidae, the present investigation largely disagrees with the species grouping established on morphological grounds.