东太平洋中部中上层鲨鱼群落营养生态位分化

鲨鱼在大洋生态系统中占据着重要的生态地位,其作为顶级捕食者,通过下行效应直接影响生态系统的稳定.稳定同位素技术是目前研究摄食生态学强有力的手段之一,可利用碳氮稳定同位素在食物网中的特性分别指示鲨鱼的食物来源和营养级.本研究选取8种130尾采集自东太平洋中部的中上层鲨鱼,应用稳定同位素绘制其种群生态位图谱,比较不同种群间的生态地位及资源分配方式上的差异.结果表明:不同鲨鱼种群碳、氮稳定同位素比值存在显著差异;8种鲨鱼在东太平洋生态系统中的营养级为4.3~5.4,大青鲨、尖吻鲭鲨与其他6种鲨鱼存在摄食隔离,表现出独特的营养生态地位.这些结果充分证明大洋性中上层鲨鱼并非生态系统的冗余种,其营养生态位的独特性不会被其他捕食者简单地替代和弥补.     

稳定同位素技术在鲨鱼摄食和洄游行为研究中的应用

随着稳定同位素分析技术的不断成熟,其在生态学领域中的应用也增长迅速,并成为动物摄食生态学的重要研究工具.鲨鱼因其在生物系统进化过程中的独特地位和海洋生态系统中的重要作用已成为海洋食物网研究的重点,然而国内针对鲨鱼摄食习性和洄游行为等方面的研究仍处于起步阶段.本文在总结了国内外鲨鱼稳定同位素分析组织样品选取和样品预处理方法的基础上,系统归纳了稳定同位素技术在鲨鱼摄食生态学,尤其在其摄食和洄游行为研究领域中的应用,着重分析稳定同位素技术在鲨鱼稳定同位素判别值和更新速率、食性分析、营养级评估、洄游路径分析和生态位分布等核心问题上的应用现状和发展前景,以期为国内学者开展鲨鱼类基础生物、生态学研究提供有益参考.     

来自海洋的危机报告

毫无疑问,鲨鱼是海上霸王。全世界的鲨鱼有30科、368种。鲨鱼的寿命一般为25岁,但有些鲨鱼可以活到100岁。鲸鲨是鲨鱼种类中体形最大的,也是海里最大的鱼类,身体直径比人还高,最大体长可达18米,体重40吨。最小的鲨鱼是侏儒鲨,最大只能长到11英寸。根据化石记录,鲨鱼发生于4亿年前,在至少经历过地球上四次生物大灭绝,其中80％地球上生物灭绝的情况下,鲨鱼劫后余生,本性不改。历经沧桑几亿年,好不容易存活下来的鲨鱼现在却由于其肝、鳍和骨头有益于人类而走向毁灭的厄运。     

中国鲨鱼资源生物学研究现状与保护对策

鲨鱼在海洋生态系统平衡中扮演着重要角色,但全球鲨鱼资源的状况不容乐观。资源生物学是评估、管理和保护资源的基础参考资料。总结了我国学者对中国海域鲨鱼资源生物学研究的成果和现状,指出了其中存在的问题,并提出了加强鲨鱼资源保护的对策。     

鲸鲨

1956年5月6日,广东省北海外沙渔业生产合作社渔民,在防城县企沙港外三墩:捕到两条极罕见的大鲨鱼,其体型及各部的结构与一般习见鲨鱼不同。当这种鲨鱼被拖到外沙海滩时曾轰动全市,许多渔民都从未见过。现经我们鉴定为鲸鲨,在过去关于我国产鲨鱼的文献中,到目前为止,还没有纪载过这种鲨鱼,因此把它的形态及特征等简单介绍出来,以供参考。     

说的都是鲨

正说到鲨鱼,除了凶猛、残暴、牙齿多,你还能想起啥?鲨鱼皮泳衣?美人鱼的小钱包?电影《大白鲨》?能够说出3条以上的你,给自己点个赞吧!要想晋级为更加优秀的鲨迷,你需要逛一逛本期指尖博物馆的鲨鱼馆。除了基础知识,这个展馆还将曝光鲨鱼的秘密往事。我是讲解员咕噜博士,欢迎你随我一起进入鲨的世界。     

鲨鱼软骨可以制药

鲨鱼软骨可以制药美国食品和药物管理局（ＦＤＡ）已批准美国新泽西州莱恩实验室的申请,将鲨鱼的软骨确定为ＩＮＤ“４７３７３研究新药的原料。莱恩实验室将用鲨鱼软骨对前列腺癌和艾滋病进行一系列的中试性！期临床试验,以确定其治疗效果。汪开治编译（根据：＆。【ｅ...     

鲨鱼减少导致其他鱼类眼睛变小

正鲨鱼是海洋中的主要捕食者。近年来由于人类大量猎杀,多种鲨鱼濒临灭绝。一项新研究发现,鲨鱼数量减少会给海洋生态系统造成重大影响,其他鱼类的形态会发生明显改变,如眼睛变小。此前研究发现,海洋中的许多小鱼都有较大的眼睛和有力的尾鳍,帮助它们及时发现并快速躲避鲨鱼。但是,西澳大利亚大学等机构研究人员发现,鲨鱼数量明显减少后,小鱼的眼睛及尾鳍也随之变小。     

谁动了美人鱼的小钱包

<正>鲨鱼妈妈已经转了好几个圈,终于在附近的海草丛中选定了一个绝佳位置作为"产房",好产下它美丽又有趣的卵。身为海洋准霸主,即便还是一枚卵,也不能有失霸气本色。鲨鱼卵的个头很大,产下来的时候就被厚厚的卵鞘紧紧包裹。鲨鱼妈妈为了保证孩子在发育过程中有足够的营养供给,还为孩子们准备了美味的卵黄作为食品保障。卵黄与鲨鱼宝宝是此消彼长的关系,随着鲨鱼宝宝慢慢长大,卵黄则会越来越小——它们要为小鲨鱼长身体腾地方。     

漫谈鲨鱼

鲨鱼是一类结构完美而特殊的动物,适应能力极强。虽然多数种类1次产仔的数量不多,但由于其后代得到较好的保护,成活率较高。随着人们对鲨鱼认识的不断提高,逐渐发现鲨鱼有很高的利用价值。     

颈斑尖猪鱼——中国南海隆头鱼科新纪录种

本文根据采自海南岛的标本描述了中国南海一新记录种:颈斑尖猪鱼(Leptojulis lambdastigma)。本种的主要形态特征为:体长形,体长为体高的3.7~4.0倍,为头长的3.1~3.6倍;头长为吻长的2.7~3.3倍,为胸鳍长的1.45~1.65倍;头裸露无鳞;两颌前端各具2对大犬齿,外侧1对犬齿弯向外后方;背鳍Ⅸ-12,臀鳍Ⅲ-12,胸鳍i(不分支)+11-12(分支);侧线完整,侧线鳞27;颈部具一个"V"形大黑斑,胸鳍后部的上方、侧线的下方具一小黑斑。新鲜标本头部具2条黄色纵带,沿体侧分别经眼和胸鳍基部向后达尾鳍基部;体侧背部具1条浅棕黄色条带;胸鳍基部棕红色,后部浅色;臀鳍浅蓝色;尾鳍下部淡蓝色,上部橙色。本种与尾斑尖猪鱼(L.urostigma)形态较为相似,主要差别在于颈斑尖猪鱼的颈部具有一显著的"V"形黑斑,尾鳍基部无黑斑(尾斑尖猪鱼具此黑斑)。     

一种长期被误鉴的中国新纪录鱼类——大鳍弹涂鱼

通过形态特征的测量和线粒体DNAcyt b基因序列分析,发现了弹涂鱼属的1个中国新纪录种,大鳍弹涂鱼Periophthalmus magnuspinnatus.新纪录种与中国近缘种弹涂鱼P.modestus的主要形态区别为:第1背鳍大而高,第1鳍棘呈丝状延长,各鳍棘尖明显伸出鳍膜;第2背鳍各鳍棘中部以下颜色均一,无黑斑;第1背鳍和第2背鳍基部之间间距较小;左右腹鳍基部愈合处凹陷较浅.序列分析表明,新纪录种与形态近似种弹涂鱼P.modestus的cyt b基因全序列平均K 2-P遗传距离高达17.3%,在分子系统树上也聚为分别属于两个不同的支序,证实了新纪录种的有效性.新纪录种在中国的渤海、黄海、东海和南海的沿海都有分布记录.     

A New Lanternshark <Emphasis Type="Italic">Etmopterus splendidus</Emphasis> from the East China Sea and Java Sea

A new species of the lanternshark Etmopterus splendidus is described. This new species is distinguished from the congeners by the combination of the following characters: distance from snout tip to 1st dorsal spine much less than distance from the spine to upper caudal origin; caudal fin short, much less than head length; dermal denticles on lateral side of trunk with very small, erect thornlike, conical crowns, those on trunk arranged in regular longitudinal rows, and distinctly arranged on interdorsal area and on lateral trunk of interspace between 2nd dorsal and caudal, but not arranged in regular longitudinal rows on dorsal surface of interorbital and o abdomen; color in life purplish-black above and with inconspicuous bluish-black flank marks and three other bluish-black marks at base of caudal fin and along its axis; shape of flank marks narrow anterior to, but broader posterior to pelvic fins.     

记比耶鱼(Birgeria)在中国的首次发现

记述了采自云南罗平晚三叠世法郎组竹杆坡段的比耶鱼一新种──刘氏比耶鱼（Ｂｉｒｇｅｒｉａ ｌｉｕｉ ｓｐ． ｎｏｖ．）,这是比耶鱼化石在中国的首次发现。刘氏比耶鱼与产自瑞士圣乔治山中三叠世边境沥青层的史氏比耶鱼最为相近,两者仅在尾柄长高之比、尾鳍长短与上下叶外缘交角、背鳍和臀鳍辐状支鳍骨的数目、臀鳍辐状骨骨板的大小、以及侧线管骨化与否等特征上略有差异。比耶鱼与软骨硬鳞鱼超目的鲟形目最为接近,两者共有一系列特征,如除尾上叶外体侧裸露,副蝶骨末端伸达头后,鳃盖骨退化;但比耶鱼同时也具有不少的特有特征,代表了软骨硬鳞鱼超目的另一类群──比耶鱼目（Ｂｉｒｇｅｒｉｉｆｏｒｍｅｓ　ｏｒｄ． ｎｏｖ．）。刘氏比耶鱼的发现进一步表明华南扬子区中、晚三叠世鱼类化石与特提斯西部的鱼群具有密切的动物地理关系。     

A new loach, Cobitis shikokuensis (Teleostei: Cobitidae), from Shikoku Island, Japan

A new species of spinous loach, Cobitis shikokuensis, is described based on 297 specimens from Shikoku Island, Japan. The new species was formerly known as the Shikoku group of Cobitis takatsuensis. It can be distinguished from other species of Cobitis and closely related genera by a combination of the following characters: dorsal fin with 6 branched soft rays; anal fin with 5 branched soft rays; one brownish streak across eye from the tip of nose, no streak on cheek; a black spot smaller than eye diameter near the dorsal corner of the caudal fin base; 3–5 small brownish speckles on ventral side of caudal peduncle; high caudal peduncle with well-developed fleshy keels on dorsal and ventral side; a lamina circularis at base of dorsal part of pectoral fin absent; first branched soft ray of pectoral fin broad in males; pectoral soft rays widely branched from the approximate midpoint; last anal fin ray with 2 elements; interorbital width 11.2–17.1% of head length.     

中国海鱼类猪齿鱼属一新纪录种腰纹猪齿鱼(鲈形目,隆头鱼科)

2012年9月,在中国南沙群岛渚碧礁采集到猪齿鱼属标本1尾,经鉴定为中国新纪录种——腰纹猪齿鱼(Choerodon zosterophorus)。本种的主要鉴别特征为:吻稍突出;背鳍ⅩⅢ-6;臀鳍Ⅲ-10;体被中大圆鳞,侧线完全,侧线鳞片27;从最后几个背鳍鳍棘基部下侧至胸鳍基部上侧之间有1条较宽白带;背侧有1较大黑色斑点,白斑背鳍后端处腹鳍位置上背部也有1较大黑点,通常在白斑处以黑色边缘线形式向前腹端延伸至腹部后侧;成体尾鳍为灰色。     

A new pearleye (Teleostei,Aulopiformes) species from the Oligocene of Romania

A new pearleye species of the alepisauroid family Scopelarchidae, Scopelarchoides neamticus sp. nov., is described herein based on two specimens from the Oligocene Lower Dysodilic Shales Formation, cropping out in the Pietricica Mountain, Romanian Eastern Carpathians. The new species described herein exhibits a unique combination of features (including head length about 25% of SL; coracoid remarkably expanded; both preorbital and postorbital lengths larger than orbit diameter; 50 or 51 vertebrae; dorsal fin with nine or ten rays; anal-fin with 28 rays; length of anal fin base about 30% of SL; preanal distance almost 60% of SL; pelvic fin insertion located just under the second dorsal fin ray; pectoral fins only slightly longer than pelvic fins; caudal fin with 19 principal rays plus 14 upper and 13 lower procurrent rays) that justifies its recognition as a new species of the genus Scopelarchoides. Both morphological and meristic features suggest a certain degree of similarity between S. neamticus sp. nov. and the extant species Scopelarchoides signifer. The fossils of the new Oligocene species described herein represent the oldest known skeletal record of Scopelarchidae.     

Acanthodes bourbonensis n.sp., ein neuer Acanthodier (Acanthodii: Pisces) aus dem Autunium (Unterperm) von Bourbon l’Archambault (Allier,Frankreich)

WithAcanthodes bourbonensis n.sp. another acanthodian from Lower Permian basins of Europe is described. The new species is similar toAcanthodes gracilis (Beyrich) from Silesia (Poland), but it differs from this and all other species of the genus in the development of the pectoral fins, dorsal fin, anal fin and caudal fin. In pectoral fins, dorsal and anal fin there are different ceratotrichia as supporting elements and pectoral fins are attaching along a row of oblonged large scales. In the caudal fin there is an epichoral appendix first found byHeyler (1969).     

Two new species and a new record of the genus Sinogastromyzon (Teleostei: Balitoridae) from Yunnan, China

Two new species and a new record of Sinogastromyzon are described from Lixianjiang River of Yunnan province, China. Sinogastromyzon lixianjiangensis, new species, can be distinguished from its congeners by the following characters: pectoral fin with XIII–XIV, 15–17 rays; pelvic fin with X–XI, 10–12 rays; 60–65 lateral-line scales; no scales on the dorsum of paired fins or the region between axilla of pectoral fin and pelvic-fin origin; tip of pelvic fin close to anus; tip of anal fin close to caudal-fin base; anal-fin origin nearer to the caudal-fin base than to the posterior pelvic-fin base; anus nearer to anal-fin origin than to the posterior pelvic-fin base; dorsal side of the body with 9–11 black blotches. Sinogastromyzon macrostoma, new species can be distinguished from its congeners by the following characters: pectoral fin with XII–XIV, 12–15 rays; pelvic fin with VII–IX, 11–13 rays; 48–56 lateral-line scales; mouth extremely big, slightly arched; no scales on the dorsum of paired fins or the region between axilla of pectoral fin and pelvic-fin origin; tip of pelvic fin far beyond anus; tip of anal fin far from caudal-fin base; anal-fin origin about midway between the posterior pelvic-fin base and caudal-fin base; anus nearer to posterior pelvic-fin base than to anal-fin origin; dorsal side of the body uniformly gray, without regular blotches in formalin preserved specimen. Sinogastromyzon cf. multiocellum is firstly recorded in China.     

Lessons from the first dorsal fin in atheriniforms—A new mode of dorsal fin development and its phylogenetic implications

The median fins in extant actinopterygians are the product of millions of years of evolution. During this time, different developmental patterns for the dorsal and anal fins emerged leading to a high variation in median fin morphology and ontogeny. In this study, the development of anal and dorsal fins in atheriniforms is described and its consequences for the current phylogenetic hypothesis are discussed. Developmental series of five atheriniform species were investigated using clearing and staining as well as antibody staining. The skeletal elements of the second dorsal fin and the anal fin emerge in a bidirectional pattern. The first dorsal fin, however, arises separately in front of the second dorsal fin after this one is almost completely formed. The pterygiophores of the first dorsal fin, including the interdorsal pterygiophores, develop from caudal to rostral, but the fin‐spines of the first dorsal fin form in the opposite direction. This new mode of fin development has been found in all examined atheriniform species with two dorsal fins. Several morphological characters of atheriniforms, including interdorsal pterygiophores, are also found in one other taxon: the Mugiliformes. Thus, several dorsal fin characteristics may provide evidence for a closer relationship of these two taxa.