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1.
Tim M. Berra 《Environmental Biology of Fishes》1997,50(1):1-12
Of the approximately 1.5 million species described to date, about 48 170 (3.2%) are vertebrates. Of these 24 618 (51%) are
fishes. Amazingly, 41% of fishes are found in fresh water which makes up a negligible percentage of the water on earth. The
sea accounts for 97% of all water on the planet and contains 58% of the fish species, mostly from shallow, warm-coastal areas.
The families Cichlidae, Cyprinidae, Characidae, Loricariidae, and Cyprinodontidae constitute about half of all the recently
described new freshwater fish species named in the period 1978–1993. The Gobiidae and Serranidae are the marine families with
the largest number of recently described new species. The most new freshwater teleost names came from South America (39%),
Africa (32%) and Asia (17%). New fish species continue to be described at the rate of roughly 130–160 each year. An estimated
13 775 new fish names have been proposed in this century, representing about 56% of all currently known fish species. Three
species are discussed in detail to represent remarkable examples of 20th century fish discoveries: the coelacanth Latimeria
chalumnae, the salamanderfish Lepidogalaxias salamandroides of Western Australia, and the megamouth shark Megachasma pelagios.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
2.
Thomas Schindler 《Pal?ontologische Zeitschrift》2018,92(4):651-660
The neotype of Rhabdolepis macropterus is revisited. Together with additional material, a new reconstruction of the skull in lateral view is presented. Main characters of this species of the family Elonichthyidae are a ventral accessory operculum which completely separates the operculum from the suboperculum, and further the border between the frontal (parietal) and the parietal (postparietal) bones lying anterior to the border between the dermosphenotic and the dermopterotic bones. The diagnosis of genus Rhabdolepis is renewed. The species Rh. macropterus is compared with the sympatric elonichthyid species Rhabdolepis saarbrueckensis and Elonichthys fritschi. 相似文献
3.
SONG Ying YAO Wei-Jian NIE PinState Key Laboratory of Freshwater Ecology Biotechnology 《动物分类学报》2008,(2)
在湖北省丹江口水库的马口鱼和宽鳍(鱼巤)的鳃上发现的寄生桡足类1新种丹江鳋。形态观察的结果表明,丹江鳋与鳋属的其他种类有很多共同特征,尤其是与博氏鳋和膨大鳋。与其它所有鳋属种类不同的是丹江鳋的第2触肢内缘光滑无刺,及其楔形第2节的外缘呈明显的弧状。以核糖体内转录间隔区(ITS)为标记进行系统进化分析,结果表明,与膨大鳋相比,博氏鳋与丹江鳋的亲缘关系更近些。无论是形态还是系统进化分析的结果都支持丹江鳋为鳋属1个独立的新种。 相似文献
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5.
A new goby (Teleostei: Gobiidae) from the South China Sea and its significance for gobioid classification 总被引:1,自引:0,他引:1
A new genus and species of gobiid fish, Egglestonichthys Patriciae , is described from the South China Sea. Certain features of the modified head lateral-line system resemble those seen in eleotrine genera with 'transverse' suborbital sensory papillae, but the skeleton of the new goby is essentially gobiine. Aspects of the lateral-line system indicate closest relationship with genera from both the IndoPacific area ( Callogobius complex, Psilogobius, Stonogobiops ) and the New World ( Microgobius ). Wider affinities with other gobiine and gobionelline genera are discussed. Discrepancies between arrangements based predominantly on lateral-line characters and on osteology are noted and their implications considered for future classification of the gobioid fishes. 相似文献
6.
Mauro Luís Triques 《Studies on Neotropical Fauna and Environment》2013,48(1):19-26
Sternopygus castroi n. sp. is described as a new species of sternopygid Neotropical freshwater fish from the Rio Cuieiras, tributary of Rio Negro, Amazonas State, Brazil. It differs from the other species of the genus by a combination of characters. Three new synapomorphies for Sternopygus are reported. Only Sternopygus species present a membranous integumental subopercular fold originating postero-ventrally in the opercular region, running anteriorly to the isthmus region. In Sternopygus, the membranous opercular opening is wide and S-shaped (wide but fleshy in Gymnotus). In Sternopygus there is also a medial cephalic fleshy fold at the ventral margin of the opercular membrane, directed forward and ventrally to the isthmus, surrounding the anal pore anteriorly, just behind the subopercular flap. 相似文献
7.
A new species of cyprinid fish, Mekongina lancangensis, is described from the upper Mekong River drainage in Southern Yunnan, China. The new species is distinguished from the other species of Mekongina occurring in the lower Mekong River drainage by possessing the following combination of characters: one pair of rostral barbels; two rows of tubercles irregularly scattered on the snout and cheeks, with two enlarged tubercles present at each side of anterior of the snout; 19–27 rostral marginal lappets; lateral line with 38–41 scales; 5·5 or 6·5 scales in transverse series from dorsal‐fin origin to lateral line; 18–20 circumpeduncular scales; snout length 31·9–36·9% head length; tip of depressed anal‐fin rays extending to the caudal‐fin base. 相似文献
8.
Abhinit Dey Hrishikesh Choudhury Abhishek Mazumder Sarbojit Thaosen Dandadhar Sarma 《Journal of fish biology》2020,96(3):642-650
Psilorhynchus nahlongthai, a new psilorhynchid fish, is described from the Diyung River, a tributary to the Kopili River (itself a southern tributary of the Brahmaputra drainage) in Assam, northeast India. It is placed in the Psilorhynchus balitora species group and can be easily distinguished from all other members of this group by a combination of the following characters: dense and prominent tuberculation on the head region; thick and long pre- and post-epiphyseal fontanelles on the neurocranium; 9 + 8 caudal-fin rays; and 34 (24 + 10) vertebrae. Genetic divergence between P. nahlongthai and members of the P. balitora species group from the Brahmaputra and neighbouring drainages, with K2P distances ranging 3.7%–14.7% and 7.4%–20.7% in the mitochondrial COI and cyt b gene datasets respectively, support its report as a new species. 相似文献
9.
A population of a trichodinid (Ciliophora: Peritrichia) was found in the gut of the surgeonfish Acanthurus xanthopterus collected from Hawaii, South Africa and New Guinea and described as a new species. This is only the second record of a trichodinid from the intestine of a marine fish. In all the fish specimens examined, the micro-fauna normally found in other species of the fish family. Acanthuridae was absent and replaced entirely by the trichodinid population. 相似文献
10.
Molecular and morphological data were used to explore evolutionary differentiation among populations of Nothobranchius in the Lake Malawi–upper Shire River and the Lakes Chilwa–Chiuta drainage systems in Malawi. The aim of the study was to test the hypothesis that Nothobranchius of the Malawi–Shire system constitute a separate evolutionary group from Nothobranchius kirki. Mitochondrial and nuclear sequence data show a strongly supported phylogenetic split into two monophyletic groups separating the Lake Malawi basin fish from N. kirki. Unlike N. kirki, Lake Malawi–Shire fish do not deviate from neutrality and express an excess of rare haplotypes and mutations in terminal branches, characteristic of recently expanded populations. Further, the two groups significantly differ in morphology. Two body characters (dorsal‐fin base length and pre‐pelvic–pre‐anal distance) are significantly different between the two species in both sexes. Several other characters are significantly different in either male or female comparisons with respect to both standard and head lengths, and robust morphological differentiation is detected by multivariate analysis. The two groups are readily distinguished on the basis of male colouration, especially in scale centres and the caudal fin. On the basis of this differentiation at the molecular and morphological levels, in addition to colouration, the Lake Malawi–Shire fish are hereby formally recognized as constituting a new species, Nothobranchius wattersi. This distinction is in agreement with the geomorphologic and recent climatic history in the region. 相似文献
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Oviposition, egg sinking rates, ion excretion in eggs and early embryos, and egg permeability and resistance to desiccation were studied in Tanytarsus barbitarsis a chironomid inhabiting highly saline waters in southern Australia. The aim was to investigate the nature of adaptations displayed by eggs and early embryonic stages of this species to life in hypersaline waters. Adaptations appear to be of two major sorts: one sort relates to the physiological stress of life in a hypersaline medium, the other to the need to minimize fish predation. The importance of selective forces other than salinity in determining the fauna of salt lakes is highlighted. 相似文献
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14.
In 1964 and 1965, two silver fish pendants depicting coelacanths and thought to be religious votive from Spanish churches were purchased on the art market in Spain, dated between the 17th and late 19th century, long before the discovery for science of the living coelacanth in 1938. It was speculated that they originated either from the Mediterranean, subtropical Atlantic, or subtropical Pacific (de Sylva 1966, Bruton 1985, Anonymous 1993, Greenwell 1994, Raynold & Mangiacopra 1995). Some authors believe that the silver fish pendants represent a new species of coelacanthiforms (Raynold & Mangiacopra 1995), others claimed the pendants to be only a wishful fantasy of scientists and not coelacanths at all (Thomson 1991). However, new studies revealed that the silver fish artefacts are indeed coelacanths but were in fact produced more recently with the Comorian coelacanth, Latimeria chalumnae, as a model. 相似文献
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16.
Paramasivam Kodeeswaran Ayyathurai Kathirvelpandian Anil Mohapatra Thipramalai Thangappan Pillai Ajith Kumar Uttam Kumar Sarkar 《Journal of fish biology》2024,104(3):737-745
A new species of the ophichthid eel of the family Ophichthidae is described based on five specimens collected from the Mudasalodai fish landing center, off Cuddalore coast, southeast coast of India, Bay of Bengal. Ophichthus naevius sp. nov. is distinguished from its congeners by having a unique color pattern: dorsal body with numerous dense dark spots or patches, ventral body pale yellowish green, dorsal-fin origin just before pectoral-fin tip, vertebral formula: 12–14/52–53/134–138, and teeth on jaw uniserial and pointed. The study also reports the range extension and molecular evidence of Ophichthus chilkensis from South India. Molecular analyses were performed for both species, and their phylogenetic relationship suggests that the new species exhibits 10.2% genetic divergence with its congener Ophichthus sangjuensis, followed by Ophichthus brevicaudatus (10.4%), and Ophichthus sp. 1 (11.8%) also forms the closest clade in both Bayesian inference and maximum likelihood (ML) tree. Similarly, according to the topology of the ML tree, the species O. chilkensis forms a clade with Ophichthus sp. 5, Ophichthus remiger, Ophichthus frontalis, Ophichthus sp. 6, and Ophichthus rex, suggesting that it would be the genetically closest congener. 相似文献
17.
依据一近完整的相关节的骨骼化石,记述了辽宁建昌早白垩世九佛堂组原始今鸟类一新属种:小齿建昌鸟(Jianchangornis microdonta gen.et sp.nov.)。新鸟个体较大,但从骨化程度分析,正型标本可能属于一亚成年个体。具有一些进步特征,如胸骨及龙骨突加长,乌喙骨具有发育的前乌喙突以及和肩胛骨关联的关节窝,叉骨"U"字型,愈合荐椎包括9-10枚荐椎,尾综骨短小,第二、三掌骨远端愈合,跗跖骨完全愈合等,表明新属无疑属于今鸟类。在以下特征组合上很容易和已知的早白垩世今鸟类化石相区别:齿骨上至少有16枚细小牙齿,从齿骨前端向后沿齿骨大部密集排列;肩胛骨强烈弯曲;第一掌骨粗壮,较其他掌骨宽;第一指长并且远端延伸明显超过第二掌骨;肱骨+尺骨+第二掌骨与股骨+胫跗骨+跗跖骨的长度比例约为1.1。系统发育分析表明新属属于基干的今鸟类。新发现的材料第二、三掌骨远端愈合很好,但近端却未完全愈合,这一特征尚未见于其他已知鸟类,或许表明今鸟类腕掌骨的愈合和现生鸟类的跗跖骨一样是从远端开始的,不同于反鸟类和其他基干鸟类。建昌鸟的下颌还保存了一个前齿骨,这是继早白垩世红山鸟之后的另一例报道,可能进一步表明这一结构在今鸟类中曾普遍出现。新鸟肩带、胸骨和前肢的特征显示了和现代鸟类相近的飞行能力,其后肢、脚趾的比例以及趾爪的形态等显示和燕鸟、义县鸟等相似的地栖特征。保存于标本上的鱼类残骸可能显示了建昌鸟食鱼类的习性。今鸟类新属种的发现进一步表明,早白垩世这一进步鸟类类群的分化已不亚于反鸟类,湖滨环境在今鸟类的早期演化中确实扮演了重要的角色。 相似文献
18.
A new species of triplefin fish (Blenniiformes: Tripterygiidae), Helcogramma williamsi, is described from six specimens collected from southern Taiwan. This species is well distinguished from its congeners by possessing 13 second dorsal-fin spines; third dorsal-fin rays modally 11; anal-fin rays modally 19; pored scales in lateral line 22-24; dentary pore pattern modally 5+1+5; lobate supraorbital cirrus; broad, serrated or palmate nasal cirrus; first dorsal fin lower in height than second; males with yellow mark extending from anterior tip of upper lip to anterior margin of eye and a whitish blue line extending from corner of mouth onto preopercle. Comparisons and a diagnostic key are provided for the species of Helcogramma now known from Taiwan: Helcogramma fuscipectoris, Helcogramma inclinata, Helcogramma striata, Helcogramma trigloides, and the newly recorded, Helcogramma rhinoceros. 相似文献
19.
A new loach Oreonectes guilinensis sp. nov. is described from Guangxi Zhuang Autonomous Region, China. It is the second surface-dwelling fish identified in the genus Oreonectes after the type species Oreonectes platycephalus. This new species can be distinguished from other species within the genus by the combination of the following features: a round caudal fin, 13–14 branched rays, an incomplete lateral line with 4–6 pores, a short pelvic fin located some distance from the anus, a scale-covered body, a stout build (body width 14.0%–16.7% of standard length), a posterior chamber of well-developed airbladder and a yellowish-brown body with a lateral dark brown strip. The maximum likelihood phylogenetic analysis based on cytb gene recovered this new species in a well-supported clade with the type species O. platycephalus, sister to the Lefua clade. Morphological comparisons as well as our phylogenetic tree support Oreonectes shuilongensis, Oreonectes daqikongensis, Oreonectes jiarongensis as species of Troglonectes. Based on our results there are 6 valid species in the genus Oreonectes. 相似文献