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石鲈科鱼类的系统发育分析兼论髭鲷属的分类地位 总被引:2,自引:0,他引:2
通过线粒体16S rRNA基因部分序列分子标记,分析了石鲈科7属15种鱼的分子系统发育关系,并通过对部分种类16S rRNA基因片段的RNA二级结构的分析,对髭鲷属分类地位进行了探讨.结果表明:15种石鲈科鱼类分为3个类群,石鲈属Haemulon、Xenistius和Anisotremus属组成类群1,矶鲈属和胡椒鲷属组成类群2,髭鲷属组成类群3;在亲缘关系上类群1和类群2较近,它们与类群3相对较远;在遗传差异上,髭鲷属与其它6个属的遗传差异接近甚至超过其与外类群笛鲷科、鲷科和隆头鱼科种类的遗传差异.在NJ和MP系统发育树中,髭鲷属与外类群笛鲷科、鲷科和隆头鱼科种类聚集在一起,石鲈科鱼类未能构成单一分支类群;同时,横带髭鲷为代表的髭鲷属鱼类16S rRNA基因长度74bp的基因片段的RNA二级结构与其余石鲈科种类存在明显的结构差异.因此,研究结果支持将髭鲷属从石鲈科中独立出来形成髭鲷科Haplogeniidae的观点. 相似文献
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M. J. F. Jarvis 《Ostrich》2013,84(4):211-216
Summary Randall, R. M., Randall, B. M., Cooper, J. &; Frost, P. G. H. 1986: A new census method for penguins tested on Jackass Penguins Spheniscus demersus. Ostrich 57: 211–215 A census method for Jackass Penguins based on their moulting cycle is described. Population estimates were substantially higher with this method than with total counts, but were not dissimilar to maximum estimates obtained from strip counts. The moult method estimates the size of the entire population and is independent of the breeding cycle and breeding status of both individuals and population. It is not plagued by the problem of absenteeism encountered during most phases of the penguin annual cycle and is independent on their diel activity. The drawbacks to the method are that it is laborious and protracted, that it does not differentiate between the breeding population and the whole population, and is unsuited to some species and some habitats. 相似文献
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耿宝印 《Acta Botanica Sinica》1989,31(7):554-560
十年前在云南省早泥盆世的地层中发现了轮生钩藻(Uncataella verticillata),限于当时的材料,其分类位置未定。本研究所用材料采自它的模式标本产地,化石植物保存良好,首次发现了着生在植物体上的雌性生殖器官——藏卵器。根据藏卵器和植物体其它部分显示的形态特征,本文修订了它的原始描述并对其系统位置进行了探讨,认为轮生钩藻是一种原始的轮藻植物,很可能属于直立轮藻目直立轮藻科中的一个成员。 相似文献
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BY Z. KABATA 《Journal of Zoology》1965,144(3):351-360
The larvae of the lernaeocerid copepods are as yet very imperfectly known. To extend the knowledge of their morphology, the larvae of Lernaeocera centropristi Pearse, 1947, were re-examined. The larvae had been discovered on the gills of Centropristus striatus (L.) in Beaufort, North Carolina. Their adult stage is still unknown. The examination has shown that the larvae are almost identical with the known larvae of Lernaeocera , but also that they are equipped with additional armament at the base of the mouth-cone. Since the presence of this armament appears to be the main distinguishing feature between the larvae of the genera Lernaeocera and Lernaeenicus , and in view of other small distinctions, it is proposed that Lernaeocera centropristi Pearse, 1947, should be transferred to the genus Lernaeenicus , as L. centropristi (Pearse, 1947). 相似文献
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本文根据对宁夏六盘山群马东山组的长鳍昆都仑鱼(Kuntulunia longipterus, Liu, Ma et Liu 1982)的新材料的研究,对其形态特征做了一些补充和订正。在此基础上,笔者支持刘宪亭等人将昆都仑鱼归入华夏鱼科(Huashiidae)及华夏鱼科归入骨舌鱼类的观点。并且认为华夏鱼类代表了一新的亚目——华夏鱼亚目(Huashioidei subordo. nov.)。 相似文献
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Some major features of the anatomy of Benthonella nisonis Dall,1889 (Gastropoda, Rissoacea) have been examined and found tojustify a new genus, Thaleia gen. nov. for the species. Itssystematic position is discussed but no certain conclusionsreached (Received 29 September 1978; 相似文献
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蒙古中部地区的三达河组(HsandaGolFormation)是亚洲渐新世陆相地层的经典地层之一。三达河组的沉积岩层现被分成两个岩性段:上部早渐新世晚期-?晚渐新世山地段(ShandMember)和下部早渐新世早期塔塔尔段(TatalMember);两岩段间有时夹有KharKhoroo玄武岩层(BryantandMcKenna,1995;MengandMcKenna,1998)。该玄武岩层的时代用40Ar/39Ar法被确定为距今31.5Ma(Hcketal.,1999,他们称其为BasaltI)。三达河组中产有丰富的哺乳动物化石,特别是啮齿类化石(MatthewandGranger,1923;Kowalski,1974;RussellandZhai,1987;Hcketal.,1999)。近年来,本文的后一作者在三达河组中又采集到一批啮齿类化石,其中包括松鼠和山河狸2科的化石。本文是对这两类化石新材料的记述。现生的松鼠科分异很大,而且大多数都分布在亚洲。然而,松鼠科化石在古近纪时在北美和欧洲却很丰富。在北美出现于晚始新世,在渐新世时已明显分异;在欧洲出现于早渐新世,在中新世时分异很大。相反,亚洲古近纪的松鼠化石却发现得很少,标本也很破碎。已报道的只有3件标本。2件产自党河下游地区:Bohlin(1946)报道的晚渐新世的Sciurussp.,标本只是2枚单个臼齿(M3和m2);王伴月、邱占祥(2004)报道的早渐新世的党河鲜松鼠(Oligosciurusdangheensis),标本只是一段带m1~2的下颌骨。还有一件是Minjin(2004)报道的蒙古渐新世的三达河克热姆鼠(Kheremhsandgoliensis),标本也只是一段带m1~3的下颌骨。本文报道的松鼠化石产自蒙古国的巴彦洪戈尔省的塔石盖贝(TashgainBel)地点的三达河组上部山地段,时代为早渐新世晚期-?晚渐新世。这批松鼠化石标本包括1件具P3~M3的上颌骨(PC369)和2段下颌骨(PC3610和PC3611)。这是亚洲古近纪目前已知的最好的一批松鼠化石标本,代表松鼠科Kherem属的一新种:亚洲克热姆鼠(Kheremasiaticasp.nov.)。其主要特征是颊齿较大,较宽;下内尖的高度和下次尖的大小从m1到m3变化不大,彼此相近;下内脊较明显;下内尖较明显,与下后边脊间有浅沟分开等。K.asiatica的形态特征表明,Kherem属应归入北美的Cedromurinae亚科。新的发现表明,亚洲渐新世的松鼠已发生了分异,至少可分为3支。以Kherem为代表的一支,与北美早期的cedromurines有较近的系统关系。它可能是由类似于北美Oligospermophilus的种类演化并迁徙到亚洲来的。现生的山河狸只有一种(Aplodontiarufa),仅生活在北美西部沿海地区。但从始新世到中新世,山河狸却遍布全北区。它们在北美较繁盛,分异大,但在亚洲发现得很少。在亚洲渐新世地层中虽曾报道过3属4种山河狸化石,但材料都很少(Prosciurusordosicus和P.?shantungensis均只有一枚单个的牙)。山河狸化石在蒙古渐新世地层的新发现表明,亚洲渐新世的山河狸化石比已知的要丰富。本文描述的山河狸化石分别采自蒙古南戈壁省Shunkt地点的山地段和前杭爱省UlaanKhongil(=TatalGol)地点的塔塔尔段。它们代表原松鼠属的3类:蒙古原松鼠(新种)(Prosciurusmongoliensissp.nov.)、蒙古原松鼠(相似种)(P.cf.P.mongoliensis)和小原松鼠(新种)(P.pisinnussp.nov.)。蒙古原松鼠的主要特征是下颊齿的下中附尖与下后附尖脊连,下中尖发育较弱,下外中脊弱或无;p4无下前边尖和下前齿带;m1具从下外脊伸向下次脊的小刺;m2和m3的下后脊II较发育;下次脊在p4和m1后弯,与下后边脊连,在m2和m3横向,伸达下外脊等。蒙古原松鼠(相似种)与蒙古原松鼠的区别是:颊齿尺寸较小,p4具明显的下外中脊,p4和m1的下次脊弯曲度较缓,m1缺从下外脊伸向下次脊的小刺,m2~3的下后脊II较短等。小原松鼠的主要特征是:个体较小;齿冠较低;下臼齿的下中附尖孤立;下颊齿的下次脊横向、较低,与下外脊连,下中尖和下外中脊均较明显,下次尖明显向前颊侧延伸,具明显的齿带等。蒙古渐新世啮齿类化石的新发现表明,亚洲渐新世的松鼠和山河狸与北美的关系要比与欧洲的近。 相似文献
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Wang Banyue Institute of Vertebrate Paleontology Paleoanthropology Academia Sinica 《古脊椎动物学报》1987,(1)
<正> Today only a single species of the aplodontid rodents still survives in the humid region of western North America, but in the Oligocene time the family was widespread over the Northern Hemisphere. Fossils of the Oligocene aplodontids so far have been mainly found in North America and Europe. Their occurrence in Asia is scarce. Only a few examples are known from Kazakhstan, USSR, and Mongolia. No record was known in China until 1977, when some fossil aplodontids were collected from the Middle Oligocene in Nei Mongol. 相似文献
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