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1.
记述了产于广东三水盆地华涌组的金龙鱼化石新材料,定为骨舌鱼科金龙鱼属一新种:三水金龙鱼(Scleropages sanshuiensis sp. nov.)。新种在头部骨骼、尾骨骼、各鳍形状和位置以及具有网状鳞片等方面与中华金龙鱼(S. sinensis)和现生金龙鱼(Scleropages)极为相似,因而归入该属。在金龙鱼属的4个现生种和中华金龙鱼之中,三水金龙鱼和中华金龙鱼更为接近。但是,三水金龙鱼在下列特征上明显不同于中华金龙鱼:鼻骨上有纹饰,第三眶下骨略小于第四眶下骨,鳃盖骨后腹缘的内凹浅,胸鳍往后延伸到腹鳍起点,躯椎上的神经棘不愈合,椎体横突长。三水金龙鱼与现生的金龙鱼也有相似之处,如鼻骨有纹饰、椎体横突长。同样,中华金龙鱼也有与现生金龙鱼相似的地方,如第三眶下骨略大于第四眶下骨、大多数躯椎上的神经棘愈合。尚不清楚三水金龙鱼和中华金龙鱼中哪一个与现生种更接近,这两个化石种可能处于相同的进化水平。中生代骨舌鱼类主要发现于中国,始新世骨舌鱼类化石在中国的发现也在逐渐增多,金龙鱼属(Scleropages)和骨舌鱼属(Osteoglossum)的共同祖先在始新世以前可能生存于东亚,并随后扩散到澳洲和世界其他地方。华涌组的骨舌鱼类和湖北松滋洋溪组的可以直接比较,因此,本项研究支持华涌组的时代为早始新世的观点。  相似文献   

2.
<正>2017年1月出版的《古脊椎动物学报》上,中国科学院古脊椎动物与古人类研究所张江永研究员和加拿大阿尔伯塔大学Mark Wilson教授报道了在我国首次发现的骨舌鱼科金龙鱼属一新种:中华金龙鱼。同时,中华金龙鱼的生态复原图作为当期的封面故事予以展示。发现于湖南湘乡的中华金龙鱼化石,是骨舌鱼科金龙鱼属的一个新种,生活时代为早始新世,距今5000万年。化石标本保存得非常完好,既为科学研究提供了确凿的证据,  相似文献   

3.
金龙鱼化石的鳞片和骨骼碎片在过去时有报道,但鉴定并非十分可靠,因为在骨舌鱼科鱼类中这些鳞片和骨骼十分相似.首次记述了保存完美的金龙鱼化石,标本产于湖南湘乡下湾铺组和湖北松滋洋溪组,确立为骨舌鱼科金龙鱼属一新种:中华金龙鱼Scleropages sinensis sp.nov..新种与现生金龙鱼(Scleropages)在头部骨骼、尾骨骼、各鳍的形状和位置以及具有网状鳞片等方面极为相似,因而归入该属.然而,新种在以下特征上不同于金龙鱼的现生种:鼻骨无纹饰,鼻骨上的感觉管显露于沟内,感觉管联合不经过顶骨,翼耳骨侧向加厚,眶前骨上的感觉孔大,眼眶后的眶下骨不完全覆盖前鳃盖骨上支,其宽高比例为0.75而非现生种的1-1.2,前鳃盖骨后下角变尖,鳃盖骨后下缘凹形、下端变尖,匙骨背突长大,脊椎46-48,椎体横突短小,胸鳍十分长大,上下两端的尾鳍条和内部鳍条等长.亚洲的现生种发现于各种河流和小溪中,比较喜欢水草茂盛的静水环境,一般游弋于表层水中,以鱼虾、昆虫等为食,新种中华金龙鱼也应该有相似的生长环境和食性.新种似具有性二形性,雄鱼体形略纤细,头部略大,口裂更深.中华金龙鱼化石的发现,说明金龙鱼属(Scleropages)和骨舌鱼属(Osteoglossum)在早始新世以前就已经分化,这对解释骨舌鱼类的跨洋分布具有十分重要的意义.  相似文献   

4.
金龙鱼化石的鳞片和骨骼碎片在过去时有报道,但鉴定并非十分可靠,因为在骨舌鱼科鱼类中这些鳞片和骨骼十分相似。首次记述了保存完美的金龙鱼化石,标本产于湖南湘乡下湾铺组和湖北松滋洋溪组,确立为骨舌鱼科金龙鱼属一新种:中华金龙鱼Scleropages sinensis sp.nov.。新种与现生金龙鱼(Scleropages)在头部骨骼、尾骨骼、各鳍的形状和位置以及具有网状鳞片等方面极为相似,因而归入该属。然而,新种在以下特征上不同于金龙鱼的现生种:鼻骨无纹饰,鼻骨上的感觉管显露于沟内,感觉管联合不经过顶骨,翼耳骨侧向加厚,眶前骨上的感觉孔大,眼眶后的眶下骨不完全覆盖前鳃盖骨上支,其宽高比例为0.75而非现生种的1–1.2,前鳃盖骨后下角变尖,鳃盖骨后下缘凹形、下端变尖,匙骨背突长大,脊椎46–48,椎体横突短小,胸鳍十分长大,上下两端的尾鳍条和内部鳍条等长。亚洲的现生种发现于各种河流和小溪中,比较喜欢水草茂盛的静水环境,一般游弋于表层水中,以鱼虾、昆虫等为食,新种中华金龙鱼也应该有相似的生长环境和食性。新种似具有性二形性,雄鱼体形略纤细,头部略大,口裂更深。中华金龙鱼化石的发现,说明金龙鱼属(Scleropages)和骨舌鱼属(Osteoglossum)在早始新世以前就已经分化,这对解释骨舌鱼类的跨洋分布具有十分重要的意义。  相似文献   

5.
《化石》2017,(3)
<正>金龙鱼是一种名贵的观赏鱼类,属于骨舌鱼超目骨舌鱼目骨舌鱼科。骨舌鱼类是真骨鱼中较古老的类群,现生骨舌鱼类除北美的舌齿鱼(Hiodon)以外,均分布于南大陆的热带和亚热带的淡水水域中,如南美的巨骨舌鱼(Arapaima)和骨舌鱼(银龙鱼,Osteoglossum),澳洲和东南亚的金龙鱼(Scleropages),非洲的异耳鱼(Heterotis)。化石骨舌鱼类基本上发现于除南极以外的世界各  相似文献   

6.
通过对中国化石骨舌鱼类及骨舌鱼类现生主要类群的比较研究,用 PAUP 软件对31个分类单元的65个特征进行了分析,得到了16个最简约的分支图(步长为206,一致性指数为 0.4320,保留指数为0.7194)。严格合意树显示,中国早白垩世的骨舌鱼类(酒泉鱼、狼鳍鱼、固阳鱼、吉南鱼、同心鱼、西夏鱼、昆都仑鱼和华夏鱼)主要为骨舌鱼超目中不同等级的干群;与一般的观点不同,始舌齿鱼与蛟河鱼组成了姊妹群关系;骨舌鱼目由 Thaumaturus、弓背鱼亚目和骨舌鱼亚目组成;弓背鱼类与象鼻鱼类关系更近;Ostariostoma 为弓背鱼科的姊妹群;副狼鳍鱼与[骨舌鱼亚科+犁齿鱼亚科]组成了姊妹群,该姊妹群关系的建立,将骨舌鱼科的历史延伸到了早白垩世。  相似文献   

7.
本文记述了辽东聂尔库组所产的骨舌鱼超目二新属——聂尔库鱼(Nieerkunia gen. nov.)、苏子鱼(Suziichthys gen. nov.)和狼鳍鱼科(Lycopteridae)属种未定的材料.文中将长头狼鳍鱼(Lycoptera longicephalus)订正为狼鳍鱼科—新属——辽西鱼(Liaoxiichthys gen. nov.),并认为聂尔库组的鱼群不同于九佛堂组的鱼群,时代属早白垩世.  相似文献   

8.
文中主要依据辽宁西部凌源、建昌、喀左、朝阳、北票、义县和阜新七个市县25个鱼化石点的新材料,对首次发现于辽西晚中生代地层中的古鳕类未定种、师氏中华弓鳍鱼、中华狼鳍鱼、三棵榆树狼鳍鱼、华夏鱼、副狼鳍鱼、聂尔库鱼和真骨鱼类未定种做了简单记述;对辽西已知的戴氏狼鳍鱼和室井氏狼鳍鱼的部分形态特征做了较详细的补充描述和订正。目前能较肯定地归入狼鳍鱼科的有狼鳍鱼、吉南鱼和固阳鱼三个属。亚洲鱼属与狼鳍鱼属仅在尾上骨的有无及尾鳍分叉鳍条的数目上有差异。狼鳍鱼属在辽西包含四个种──戴氏、室井氏、中华和三棵榆树狼鳍鱼。辽西的德永氏狼鳍鱼应为戴氏狼鳍鱼的同物异名。常氏鱼和辽西鱼均为吉南鱼的晚出异名。副狼鳍鱼的形态特征已与骨舌鱼科的现生种类很相近,可将其归入该科。山东的宁家沟谭氏鱼是张氏副狼鳍鱼的同物异名。  相似文献   

9.
浅谈肺鱼     
冯照军 《化石》1992,(3):13-13
众所周知,鱼类通常用鳃呼吸,用鳔来调节身体的比重。但有些鱼类可以用鳔呼吸,如肺鱼、多鳍鱼、全骨鱼类、巨骨舌鱼、荫鱼、长颌鱼、脂鲤等。在此重点谈谈闻名世界的肺鱼类(Bipnoi)。肺鱼是一类与总鳍鱼有着类似历史的古老动物,它出现于早泥盆纪,并在二迭纪时繁盛起来。到了三迭纪时,肺鱼的种类和数量均大为减少。至今全世界现存肺鱼仅三属六种,且均生活在淡水中,学者们称之为“活化石”。这三个属是:澳大利亚肺鱼属(Neoceratodus),亦称“新角齿鱼”,是较原始的类群,如澳大利亚肺鱼[N.forsteri  相似文献   

10.
本文记述了产自苏北沭阳阜宁群上部的一始舌齿鱼,依据它在外形、鼻骨及尾部结构上与始舌齿鱼现有种的区别,将它定为一新种:沭阳始舌齿鱼(Eohiodon shuyangensis ,sp.nov.)。同时,本文对骨舌鱼类的历史动物地理学问题作了尝试性的分析。  相似文献   

11.
The neurohypophysis of three species of the Osteoglossidae (Osteoglossum bicirrhosum, Scleropages jardini and Heterotis niloticus) was studied histologically. The rostral part of the neurohypophysis abuts on the pars distalis of the adenohypophysis, but does not interdigitate with it. The caudal part of the neurohypophysis is stained densely with aldehyde fuchsin and extensively interdigitates with the pars intermedia, forming a neurointermediate lobe. This organization of the neurohypophysis is intermediate between that of holosteans and that of non-osteoglossomorph teleosts. The median eminence-like features of the rostral part of the neurohypophysis are distinct in the Osteoglossidae in contrast to non-osteoglossomorph teleosts. In Osteoglossum bicirrhosum, immunohistochemical study reveals the presence of somatotropin release-inhibiting factor-like substance in the rostral part of the neurohypophysis. Fibers immunoreactive to anti-arginine vasopressin occur in the neurointermediate lobe almost exclusively. These observations also may support the assumption that the rostral part of the neurohypophysis corresponds functionally to the median eminence. For comparison, the occurrence and distribution of somatotropin release-inhibiting factor-like substance, luteinizing hormone-releasing factor-like substance and arginine vasopressin-like substance in the neurohypophysis of Gymnarchus niloticus are described.  相似文献   

12.
Although the ray‐finned fishes are named for their bony, segmented lepidotrichia (fin rays), we are only beginning to understand the morphological and functional diversity of this key vertebrate structure. Fin rays support the fin web, and their material properties help define the function of the entire fin. Many earlier studies of fin ray morphology and function have focused on isolated rays, or on rays from only one or two fins. At the same time, relatively little is known about how different preservation techniques affect the material properties of many vertebrate structures, including fin rays. Here, we use three‐point bending tests to examine intra‐ and inter‐fin variation in the flexural stiffness of fin rays from yellow perch, Perca flavescens. We sampled fin rays from individuals that were assigned to one of three preservation treatments: fresh, frozen, and preserved with formalin. The flexural stiffness of the fin rays varied within and among fins. Pelvic‐fin rays were the stiffest, and pectoral fin rays the least stiff. The fin rays of the dorsal, anal, and caudal fins all had similar stiffness values, which were intermediate relative to those from the paired fins. The flexural stiffness of the fin rays was higher in rays that were at the leading edge of the fin. This variation in flexural stiffness was associated with variation in joint density and the relative length of the unsegmented proximal base of the fin rays. There was no significant difference in flexural stiffness between fresh and frozen specimens. In specimens preserved with formalin, there is a small but significant effect on stiffness in smaller fin rays.  相似文献   

13.
A new marine goby Callogobius sheni collected from coral reefs off southern Taiwan is described. The new species can be distinguished from congeneric species by the following combination of features: dorsal fin rays VI-I, 9; anal fin rays I, 7; pectoral fin rays 18; longitudinal scale rows 27–28; predorsal scale rows 9–10; no posterior oculoscapular and preopercular canals; body pale white with five blackish brown cross bands; caudal and pectoral fins each with a large blackish brown blotch.  相似文献   

14.
陕北延长群一新古鳕类及其生物地层意义   总被引:9,自引:6,他引:3  
本文记述了在陕西北部耀县铜川组发现的古鳕科一新属、种——延长三叠鳕(Triassodusyanchangensis,gen.et sp.nov.)。在对其形态特征作较详细描述的基础上,认为它既与美国晚三叠世的吐鲁瑟欧鳕(Turseodus)很接近,又与我国四川须家河组(晚三叠世)的蜀鳕(Sh-uniscus)相似。基于上述的理由,认为铜川组的时代是晚三叠世。根据迄今在我国晓三叠世发现的鱼类,探讨了我国晚三叠世的鱼群与北美的关系。  相似文献   

15.
The osteological development of the head skeleton and dorsal, pectoral, and anal fin supports, are described from cleared and stained specimens ofLophius gastrophysus larvae, ranging from 4.6 to 21.8 mm NL; the results are compared with those of juvenile (79.8 mm SL) and adult (398 mm SL) specimens. Tiny conical teeth are present on the premaxillary, dentary, palatine and vomer since early stage. The first three dorsal fin spines are initially positioned on the midline of body posterior to the supraoccipital, but they migrate forward with growth and become cephalic in juveniles. The forward movement of the dorsal spines is produced by the forward extension of the cartilaginous basal inside the subepidermal space. During the planktonic larval stage the pectoral fins are on the sides of body as in ordinary fishes, but they move ventrad and become leg-like in bottom living juveniles and adults. Ossification of the caudal complex ofL. gastrophysus larvae proceeds very slowly and only the 21.8 mm NL larva has an almost completely ossified caudal complex. Eight principal caudal rays are loosely attached on the posterior edge of the hypurals and no procurrent rays are present. Larvae have well developed parhypurapophysis at the mid-portion of the urostyle which transforms into keel-like structure in juveniles and adults.  相似文献   

16.
Specimens of a new genus and species of the stichaeid fish,Leptostichaeus pumilus, were collected from the Okhotsk Sea off Hokkaido in Japan. The present new genus and species clearly differs from all the other genera and species of the stichaeid fishes in the following characters: 3 or 4 pectoral fin rays; 10 or fewer caudal principal rays; 79–82 dorsal spines; no pelvic fin; last interneural spine supporting a single dorsal spine; infraorbital, occipital and lateral line canals absent; moderate size of dorsal spine shorter than eye diameter; membranes of dorsal and anal fins widely connected with caudal fin; a large black spot divided by a yellow band present just above gill cover.  相似文献   

17.
A new genus and species of the subfamily Bythitinae (Bythitidae),Hastatobythites arafurensis, is described on the basis of two specimens from the Arafura Sea. The genus is unique in the subfamily in having two anteriorlydirected spines, one on the frontal and one on the mesethmoid. It is also distinguishable from all other genera in the subfamily by the following combination of characters: head scales absent; squamation on body incomplete; maxillary expanded posteriorly; no thin pore-bearing skin flap over opercle; opercle thin, weak, without distinct spine; jaw teeth conical; vomerine and palatine teeth present; developed gill rakers on 1 st arch 3; pelvic fins with 1 ray in each; pectoral peduncle elongated, with 16 rays; caudal fin rays 12; branchiostegal, rays 8; precaudal vertebrae 15, with tips of 6th to 12th neural spines truncated.  相似文献   

18.
宁夏狼鳍鱼科一新属   总被引:3,自引:2,他引:1  
本文记述了狼鳍鱼科一新属,即同心鱼属(Tougxinichthys gen.nov.)化石产自宁夏同心县康家湾;海原县石峡口一带的六盘山群上部。同心鱼(Tongxinichthys)与狼鳍鱼(Lycoptera)很相似。后者被认为是我国华北地区晚侏罗世鱼群的主要成员。而同心鱼的某些特征较为进步。因此,同心鱼的生存时代有延续到早白垩世早期的可能性。同心鱼的发现,增加了狼鳍鱼类的新成员。对狼鳍鱼类的形态解剖,系统演化,及亲缘关系的深入研究,提供了新的资料。  相似文献   

19.
内蒙古石拐群古鳕类一新属   总被引:2,自引:2,他引:0  
内蒙古石拐地区石拐群召沟组中的长腹鳍大青山鳕(新属、新种) Daqingshaniscus longiventralis gen. et sp. nov. 是在我国中侏罗世地层中发现的一比较原始的古鳕类.其头骨眶后部分短,鳃盖骨大于下鳃盖骨,背鳍位于腹鳍与臀鳍之间,腹鳍基线长,鳍条都从基部分节、远端分叉,棘鳞仅见于尾上叶,全歪型尾,鳞片呈菱形.大青山鳕既与苏联南哈萨克斯坦 Karatau 地区的 Pteroniscus 很接近,又与我国新疆的维吾尔鳕 Uighuroniscus 及西德北部的 Stadthagen 地区的 Indaginilepis 相似.  相似文献   

20.
Ray‐finned fishes actively control the shape and orientation of their fins to either generate or resist hydrodynamic forces. Because of the emergent mechanical properties of their segmented, bilaminar fin rays (lepidotrichia), and actuation by multiple muscles, fish can control the rigidity and curvature of individual rays independently, thereby varying the resultant forces across the fin surfaces. Expecting that differences in fin‐ray morphology should reflect variation in their mechanical properties, we measured several musculoskeletal features of individual spines and rays of the dorsal and anal fins of bluegill sunfish, Lepomis macrochirus, and assessed their mobility and flexibility. We separated the fin‐rays into four groups based on the fin (dorsal or anal) or fin‐ray type (spine or ray) and measured the length of the spines/rays and the mass of the three median fin‐ray muscles: the inclinators, erectors and depressors. Within the two ray groups, we measured the portion of the rays that were segmented vs. unsegmented and branched vs. unbranched. For the majority of variables tested, we found that variations between fin‐rays within each group were significantly related to position within the fin and these patterns were conserved between the dorsal and anal rays. Based on positional variations in fin‐ray and muscle parameters, we suggest that anterior and posterior regions of each fin perform different functions when interacting with the surrounding fluid. Specifically, we suggest that the stiffer anterior rays of the soft dorsal and anal fins maintain stability and keep the flow across the fins steady. The posterior rays, which are more flexible with a greater range of motion, fine‐tune their stiffness and orientation, directing the resultant flow to generate lateral and some thrust forces, thus acting as an accessory caudal fin. J. Morphol., 2012. © 2011 Wiley Periodicals, Inc.  相似文献   

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