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荔波洞穴鱼类初步研究 总被引：9，自引：3，他引：6
荔波县位于贵州南部,地下河及洞穴发育,洞穴水体中鱼类亦很丰富。经过对100个洞穴的考察研究,在地下河中及地下河出、入口处共采集到鱼类标本200余号,经鉴定为37种,其中真洞穴鱼类3种,好洞穴鱼类10种,偶洞栖鱼类24种。真洞穴鱼类特化最高,对洞穴环境的依赖性很强,好洞穴鱼类有一些特化现象。 相似文献
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本文依据近年来在江西武宁清水组及安徽宁国唐家坞组中新发现的含鱼层位,结合古鱼类形态学与系统学研究结果,对中国含志留纪早期鱼化石的主要层位进行梳理,认为:(1)浙西北地区产曙鱼科和修水鱼科化石的地层为唐家坞组,属于下红层,而非上红层茅山组;(2)皖东南地区产大庸鱼科化石的地层为唐家坞组,属于下红层;(3)依据所产的大庸鱼科、汉阳鱼科、古木鱼科等原始盔甲鱼类化石,苏皖地区侯家塘组属于下红层;(4)根据古鱼类化石,华南的溶溪组、清水组、唐家坞组、侯家塘组与新疆塔里木盆地的塔塔埃尔塔格组可以直接对比,时代为志留纪兰多维列世特列奇早期。基于古鱼类化石新认识,本文修订了产于湖南下红层中的温塘鱼类化石组合,该组合主要以盔甲鱼亚纲中的基干盔甲鱼类(汉阳鱼科、修水鱼科、大庸鱼科)、最原始的真盔甲鱼类(曙鱼科)、最原始的多鳃鱼类(古木鱼科)与软骨鱼类中的中华棘鱼类的出现与繁盛为特征。 相似文献
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回顾二十年来我国古生代鱼类微体化石的研究工作,该项研究由起步而后成为我国古生代鱼类研究工作的一个重要组成部分,填补了鱼类大化石涉足不到的许多研究领域、也填补了我国古生代微体化石研究中脊椎动物微体化石(主要指无颌类和鱼类,也简称为鱼类)这一重要的空白。我国已发现的古生代鱼类微体化石产自属于不同相区的54个岩组中,包括无颌类和鱼类共7个亚纲的化石。对这些鱼类微体化石进行了形态学、古组织学、生物矿物学、分类学和系统发育学的研究;在此基础上进行了生物年代学、生物地层学和界线层型的研究,特别是建立了志留纪、泥盆纪和石炭纪鱼类微体化石组合序列,个别成熟的岩段建立了生物带;研究了泥盆系-石炭系界线和二叠系-三叠系界线上下的鱼类微体化石;长兴煤山二叠纪末鱼类的集群绝灭发生的很晚,持续的时间很短,规模很大,绝灭率高达93%;华南早三叠世鱼类的复苏和辐射相当快,从绝灭期到辐射期仅用了1.3Myr到4Myr;塔里木盆地中古生代红色岩系应属于一种滨海环境、塔塔埃尔塔格组和依木干他乌组含软骨鱼群地层的时代为早志留世特里奇期(Telychian);利用贵州和塔里木盆地存在相近的软骨鱼群成功地进行了海相—非海相对比研究,从而判定软骨鱼群中至少存在一部分广盐性鲨类,两地具相近的软骨鱼群和塔里木盆地含有华南中古生代普遍存在的盔甲鱼类进一步表明华南板块与塔里木板块在中古生代应属于同一个古动物地理区。在综述所取得的成果的同时对今后的研究工作进行了展望。 相似文献
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区域地球化学、地球物理资料在四姑娘山地区生态环境评价中的应用 总被引：4，自引：1，他引：4
利用区域地球化学和区域地球物理资料，研究了四姑娘山地区生态环境地质背景，讨论了该区异型沙棘和鱼类有选择生存两种特异生态环境现象产生了可能原因。 相似文献
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初步探讨了峡江地区先秦时期鱼类资源的开发情况,包括种类结构及其历时性变化、整体地位及其背后的原因。对21处遗址中经科学鉴定的鱼骨材料的统计显示,该地区先秦时期(8.5kaB.P.至东周)鱼类开发的种类结构相当稳定——一直重点开发青鱼和草鱼,二者可占总量的70%~80%,同时表现出较明显的区域差异,即东区(湖北段)优先开发青鱼,而西区(重庆段)优先开发草鱼。鱼类资源开发在当时先民的经济生活中扮演了关键角色,如3处经严格筛选取样的遗址中鱼骨的可鉴定标本数均占出土动物骨骼总数的70%以上;它同时在先民的精神文化方面留下了深刻印记,如流行整鱼随葬和鱼骨占卜。这些遗存和现象具有鲜明的地域特色,反映了峡江地区特殊的峡谷环境及丰富的鱼类资源对人类生计方式与文化行为的制约与影响,表明对鱼类资源的优先开发是当地先民的一种环境适应与文化选择。 相似文献
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江苏句容早三叠世鱼类化石之发现及其意义 总被引：1，自引：0，他引：1
记述了江苏句容下三叠统青龙组下三叠统青龙组下部地层中发现的软骨硬鳞鱼类一新种－江苏裂齿鱼和半椎鱼类一新种－句容鳞齿鱼化石，并讨论了其分类特征、生存环境及化石埋藏状况。 相似文献
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盔甲鱼类是古生代中期化石无颌类的主要类群,其分布主要限于我国境内以及越南北部。至目前为止,在我国已发现并鉴定的盔甲鱼类计有48属68种,其中志留纪14属19种,遍布川、陕、鄂、湘、皖、浙、赣、新等省;泥盆纪35属49种,遍布宁、川、黔、桂、滇等省（区）。本文不仅对含盔甲鱼类的地层进行了详细的对比研究,而且根据盔甲鱼类在中古生代地层中出现的先后顺序,自下而上划分了9个盔甲鱼化石组合与1个盔甲鱼层,并认为这些化石组合和盔甲鱼层之间的演替与当时环境条件的变化及古地理、古构造的变迁密不可分。另外,通过对盔甲鱼类形态学及古生态学的研究,认为盔甲鱼类应是一类行底栖滤食性生活、运动能力不强的类群,其主要生活环境为靠近古陆边缘的海域。由于其迁移扩散能力有限,宽广的陆地以及宽阔的海洋均成为其迁移、扩散的障碍,因此盔甲鱼类具有重要的古生物地理意义。最后,根据盔甲鱼类在我国的地理分布特征,并结合大地构造学及古地磁学方面的资料,对中古生代我国三大主要板块之间的古地理关系进行了初步的探讨性研究,结果表明：古生代中期中国三大板块具有十分密切的古地理关系,它们彼此相接或相邻,并同属于一个鱼类动物地理区系即泛华夏盔甲鱼类区系。 相似文献
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Cristina Lombardo 《Swiss Journal of Geoscience》2013,106(2):219-230
A new taxon of Late Ladinian basal actinopterygian is described on the basis of a single specimen from the Meride Limestone (Kalkschieferzone) of Meride (Canton Ticino, Switzerland). The species is characterized by a single plate-like branchiostegal, a suboperculum larger than the operculum, a maxillary fixed and posteriorly expanded, a large and rectangular dermopterotic and a large triangular dermosphenotic; the scales are rectangular to rhomboidal, the lepidotrichia of median fins are segmented from their base and the caudal fin shows epaxial rays. These features resemble the condition of the Redfieldiiformes, a freshwater fish group, whose presence in Europe is still controversial, owing to poor preservation of specimens found so far. 相似文献
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记述了产自云南中三叠世的裂齿鱼类3个新属种——邓氏富源裂齿鱼(Fuyuanperleidus dengi gen.et sp.nov.)、苏氏罗平裂齿鱼(Luopingperleidus sui gen.et sp.nov.)和小齿滇东裂齿鱼(Diandongperleidus denticulatus gen.et sp.nov.)。邓氏富源裂齿鱼区别于其它裂齿鱼的特征,包括上颌骨形状、上下颌牙齿大小及形状、头骨纹饰、上颌骨与第一眶下骨愈合、高鳞片。苏氏罗平裂齿鱼区别于其它裂齿鱼的特征,包括三角形的鳃条骨、腹鳍前有4列水平方向的高鳞片、3个臀鳞。小齿滇东裂齿鱼区别于其它裂齿鱼的特征,包括胸鳍、腹鳍、背鳍和臀鳍前面鳍条的前缘具有小锯齿,鳞片后缘具有许多小锯齿。裂齿鱼类的新发现不仅丰富了中国华南裂齿鱼类的多样性,而且提供了裂齿鱼类在三叠纪全球辐射的新信息。 相似文献
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鲟形鱼类是一类脊椎骨尚未完全骨化、鳞片极度退化的原始辐鳍鱼类。本文重新系统描述了该类别中时代最古老的中华原始软骨硬鳞鱼(Eochondrosteus sinensis Lu,Li et Yang, 2005),补充并修订了其古生物学特征。该鱼类具有扇形的下鳃盖骨、多块条形鳃条骨、较大的喉板骨、具齿的上、下颌,且全身仅在尾鳍上叶具有鳞片等特征,可以区别于鲟形鱼类其他属种。初步的支序系统发育分析表明,Eochondrosteus可能是鲟形鱼类中最原始的类群,与所有其他鲟形鱼类的祖先类群构成一个姐妹群;同时其具有一些古鳕类才普遍拥有的特征,如相对较大的喉板骨和眶下骨等,有可能是原始辐鳍鱼类向鲟形鱼类进化过程中的过渡类型。这一鲟形鱼类化石产于甘肃省肃北县马鬃山镇西北约50 km的方山口组深灰色粉砂质页岩中。根据野外实地调查和岩石地层学、生物地层学对比,该鱼类的时代有可能是早三叠世,而非命名时认为的晚二叠世,但仍是迄今已发现的时代最古老之鲟形鱼类。 相似文献
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The Coccondontoidea is a distinctive superfamily of pycnodont fishes characterized by a series of derived characters, including thick and well-ossified cranial bones supporting horns and spines and a hypertrophied pectoral girdle sutured to the skull forming a sort of cephalo-torax. A new distinctive coccodontoid species, Gladiopycnodus byrnei n. sp., is described from the Cenomanian locality of Hjoûla, Lebanon. This new species exhibits a unique combination of features that clearly support its inclusion within the coccodontoid family Gladiopycnodontidae, including an extremely elongate snout forming a sword-shaped rostrum, thick dermal bones ornamented with rounded tubercles, large supracleithrum and cleithrum extensively sutured to the skull, and irregularly imbricated scales covering the entire body. The new taxon differs from type species G. karami by having different meristic counts and body proportions, dermal bones strongly ornamentated, skull roof with partially fused bones, scales ornamented with small tubercles, and rounded scales covering the caudal peduncle absent. The presence of pectoral fins in our exquisitely well-preserved specimen allowed us to redefine the morphology of the genus Gladiopycnodus, also modifying the diagnosis of the family. In order to interpret the patterns of morphospace occupation and quantify the morphological diversification of pycnodonts through time, the geometric morphometric approach was used. The morphospace analysis revealed that a significant increase in morphological disparity of pycnodonts during the Late Cretaceous was related, at least in part, to the appearance of the representatives of the superfamily Coccodontoidea. The rapid evolutionary radiation of these well-armored pycnodonts was interpreted as an adaptive solution in response to the large predatory-prey escalation in the context of the Mesozoic Marine Revolution. 相似文献
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A new genus and species of clupeomorph fish, Leufuichthys minimus, is described from the fluvial deposits of the Portezuelo Formation, Upper Cretaceous (Turonian-Coniacian) of the Neuquén Group, Patagonia, Argentina. It is a small-sized fish with an estimated body length up to 46 mm. Among other characters, the new species shows the following: abdominal scutes; abdomen moderately convex; anal fin elongate-based; three uroneurals; two epurals; caudal fin bearing very elongate rays; and cycloid scales. Leufuichthys minimus gen. et sp. nov. shows a greater similarity with Kwangoclupea dartevellei, a clupeomorph described from a marine Cenomanian deposit of the Democratic Republic of Congo (Africa), mainly due to the presence of an elongate-based anal fin, bearing more than 20 fin-rays, differing from it by the presence of a not hypertrophied abdomen. As far as known, L. minimus gen. et sp. nov. is the first clupeomorph described in the Upper Cretaceous of Patagonia and represents one fortuitous preservation of an articulated fish in fluvial deposits. 相似文献
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New coelacanth material from the Middle Triassic Prosanto Formation of the Ducan and Landwasser area near Davos in eastern Switzerland, Canton Graubünden, is described. A sub-complete individual is visible in ventral view, and shows details of its branchial apparatus. In particular, it possesses relatively large teeth on the ceratobranchials, and possible ossified hypobranchials. Few diagnostic characters are observable, and most of them are visible on the mandibles preserved in lateral view. This specimen shares characters with Ticinepomis peyeri, a smaller form from the Middle Triassic of Monte San Giorgio, whose holotype is re-described in part here. A second specimen, a fragmentary caudal skeleton shows the typical supplementary lobe of coelacanths, and meristic characters indicating probable close affinities with T. peyeri. We refer this material to Ticinepomis cf. T. peyeri. Because the new specimen is larger than the holotype, we refute the possible juvenile status of the small specimen from Monte San Giorgio. The new material of Ticinepomis from Canton Graubünden shows anatomical features not preserved on the holotype and allows the addition of new characters to a previously published data matrix of actinistians. A phylogenetic analysis is performed, which supports that Ticinepomis is nested among the Latimeriidae. The diversity of post-Palaeozoic coelacanths is assessed. The taxic diversity of observed occurrences shows a peak in the Early Triassic and a peak in the Late Jurassic, as detected in previous studies. When ghost lineages are included in the computation, the Late Jurassic peak is smoothened. By comparing the taxic diversity curves with the curve of average ghost lineage duration, we conclude that the Early Triassic peak of diversity was probably caused by a biological radiation, whereas the Late Jurassic peak of observed diversity is probably the result of a Lagerstätten effect. 相似文献
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运用遗迹化石恢复造迹动物的形态结构是古遗迹学研究的难点.近年来在陕北横山晚三叠世地层中发现大量完好的鱼类游泳遗迹, 能较好地恢复造迹鱼类鳍的着生位置及相关形态结构, 确定造迹鱼的类型.通过游泳遗迹的形态结构与鱼类形态结构相互关系的分析, 建立了游泳遗迹形态结构参数与造迹鱼类形态结构参数之间的数学关系式.通过计算显示同一遗迹种的鱼鳍间距与鱼体长度比值一定, 这与现代鱼类形体特征一致.应用该方法恢复了研究区两遗迹种的造迹鱼类, 其中Undichna britannica造迹鱼类的尾鳍和臀鳍间距与体长之比为0.3, 臀鳍和胸鳍间距与体长之比为0.45~0.5, 尾鳍和腹鳍间距与体长之比为0.49~0.5, 与邻区相同层位发现的鱼类实体化石Wayaobulepis zichangensis相关特征一致.另一遗迹种Undichna tricosta恢复的尾鳍和臀鳍间距与体长之比约为0.35, 可能与本区相同层位发现的Saurichthys huanshenensis特征相似. 相似文献
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A new genus and species of percoid fish, Hendrixella grandei gen. & sp. nov. is described from the upper Ypresian limestone of Monte Bolca, Italy. It is based on four well-preserved
specimens that show an elongate and slender body and a unique combination of features, including possession of 11 + 13 vertebrae,
two series of intermuscular bones, fused haemal spine of third preural centrum, caudal fin with 17 principal rays and 11 upper
and eight lower procurrent rays, predorsal formula 0/0/1 + 1/1/, two separated dorsal fins with rayless pterygiophore in-between,
and a single supernumerary spine in both dorsal and anal fins. Due to this unique combination of features, Hendrixella cannot be placed within any existing fossil or extant percoid families and it is placed incertae sedis in the Percoidei. The possession of two series of intermuscular bones represents an unambiguous autapomorphy of Hendrixella. A comparative analysis of the distribution of intermusculars among percomorph fishes indicates that the intermuscular bones
of the upper series can be homologized with the epineurals and those of the lower series are the homologs of the epicentrals
of non-acanthomorphs. 相似文献
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<正>A new species of gymnospermous fossil wood,Protophyllocladoxylon jingyuanense sp.nov., is described from the lower part of the Tsingyuan Formation(Serpukhovian/Late Mississippian),near the coal mine of Ciyao,Gansu,northwestern China.The specimen is preserved only in silicified secondary xylem,while growth rings are absent.Pits in radial tracheidal walls are araucaroid in type, uniseriate,occasionally biseriate.Xylem rays are homogeneous,uniseriate,occasionally biseriate. Cross-field pits are simple,large,one to two in number.Axial parenchyma is absent.The anatomical characters and geographic distribution of Protophyllocladoxylon woods through geological ages are documented.Those species with axial parenchyma and without growth rings live in warm climate, whereas the species without axial parenchyma and with growth rings are present either in warm or cool climate.The ideal living climate for Protophyllocladoxylon woods is warm and wet.Our new species,as a fossil wood of Early Carboniferous,is likely the earliest known species of Protophyllocladoxylon. 相似文献