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1.
The molecular phylogeny of the gobioid fishes, comprising 33 genera and 43 valid species, was examined by use of complete mitochondrial 12S rRNA and tRNA(VAL)genes. Both parsimony and neighbor-joining analyses revealed comparable results and are generally congruent with those of morphological studies. The Odontobutis, which was always placed at the base of the phylogenetic trees, can be treated as a sister group of all other nonrhyacichthyid gobioids. Within eleotrid fishes, the monophyly of the Eleotrinae is strongly supported by molecular data. The Butinae is closer to fishes with five branchiostegal rays and should be treated as a sister group of the latter. The group with five branchiostegal rays, except for sicydiines, can be divided into two groups according to their epural counts. Fish with one epural, the Gobiinae of Pezold plus Microdesmidae, form a monophyletic group which is sister to those with two epurals, the Oxudercinae and Gobionellinae of Pezold. However, Sicydiinae, which have one epural, are closer to the Oxudercinae and Gobionellinae rather than to the Gobiinae. Since progressive reduction in epural number has been observed along this lineage, the sicydiines should be treated as a derived group within the groups with two epurals.  相似文献   

2.
Konstantinidis P. and Johnson, G. D. 2012. A comparative ontogenetic study of the tetraodontiform caudal complex. —Acta Zoologica (Stockholm) 93 : 98–114. Interpretation of the caudal complex of adult Tetraodontiformes has proven problematic because of the consolidation of the component elements. Here, we show that an ontogenetic approach offers considerable elucidation of the homology of the caudal complex, resulting in a new understanding of the grundplan of these fishes. The reductions of structures of the caudal complex are interpreted in a phylogenetic context. The caudal skeleton of larval triacanthodids resembles that of many adult percomorphs; however, during subsequent development epural 3 disappears, while epural 2 is reduced so that it can hardly be distinguished from the uroneural remnants. Juvenile triacanthids have an epural 2 that is lost in ontogeny, and the cartilaginous parhypural becomes integrated into the large hypural plate. In ostraciids and diodontids, the parhypural is absent throughout development. The hypural plates of adult balistids, monacanthids and tetraodontids have a conspicuous diastema between the dorsal and ventral portions. However, in early stages of the former two, the dorsal and ventral portions are continuous in cartilage proximally and remain fused in the adults. In tetraodontids, the two hypurals are separate from their initial appearance in cartilage and never fuse, raising the question of homology of the individual hypurals among the different families.  相似文献   

3.
The different elements of the caudal skeleton of the South American catfish genera Nematogenys (Nematogenyinae) and Trichomycterus, Hatcheria, and Bullockia (Pygidiinae) (Siluriformes, Trichomycteridae) show Ontogenetic transformation of the second ural centrum in Trichomycteridae separates the subfamilies Nematogenyinae and Pygidiinae. In the former, the second ural centrum is aligned with the first ural centrum in early stages of ontogeny; it is not fused with the bases of hypurals 3 and 4 in any stage of development. In the Pygidiinae, in contrast, the second ural centrum is connected with the base of hypural 3 from an early stage of development on. One of the most noteworthy features of the Pygidiinae is the epural, a polymorphic element with three or four morphotypes that are species specific. The primitive catfish Nematogenys shows intraspecific variation in the ural centra, segmentation of procurrent caudal rays, and principal caudal ray formulae. Species of Trichomycterus, Hatcheria, and Bullockia are characterized by great intraspecific variability that involves ural centra, the epural, hypurapophyses, and the neural arches of the compound centrum. There is intraspecific variation in the fusion of the hypurals in some species of Trichomycterus. Intraspecific variation of the caudal skeleton of fishes of the family Trichomycteridae involves the presence and frequency of different morphotypes of the epural, neural arch of the compound centrum, fusion of hypurals, and principal caudal ray formulae. Ontogenetic changes of the first and second ural centra, hypurapophyses (with the exception of Nematogenys), and segmentation of procurrent caudal rays (in Nematogenys) are involved also.  相似文献   

4.
The vertebral centra of Hiodon, Elops, and Albula are direct perichordal ossifications (autocentra) which enclose the arcocentra as in Amia. An inner ring of ovoid cells forms in late ontogeny from the intervertebral space inside the autocentrum. The chordacentrum is reduced or completely absent in centra of adult Elops, whereas it forms an important portion of the centra in adult Hiodon. The posterior portion of the compound ural centrum 3+4+5 is partially (Hiodon) or fully formed by the chordacentrum (Elops, Albula). The haemal arches and hypurals are fused medially by cartilage or bone trabecles of the arcocentrum with the centra, even though they appear autogenous in lateral view in Elops and Albula. The composition of the caudal skeleton of fossil teleosts and the ontogeny of that of Hiodon, Elops, and Albula corroborate a one-to-one relationship of ural centra with these dorsal and ventral elements. The first epural (epural 1) of Elops relates to ural centrum 1, whereas the first epural (epural 2) of Hiodon and Albula relates to ural centrum 2. In Albula, the first ural centrum is formed by ural centrum 2 only. With 4 uroneurals Hiodon has the highest number within recent teleosts. Juvenile specimens of Hiodon have eight, the highest number of hypurals within recent teleosts; this is the primitive condition by comparison with other teleosts and pholidophorids. Reduction of elements in the caudal skeleton is an advanced feature as seen within elopomorphs from Elops to Albula. Such reductions and fusions occur in osteoglossomorphs also, but the lack of epurals and uroneurals separates most osteoglossomorphs (except Hiodon) from all other teleosts.  相似文献   

5.
We describe the ontogeny of the axial skeleton and median fins of the Southeast Asian freshwater puffer Monotrete leiurus, based on a reared developmental series. Most elements of the axial skeleton in M. leiurus arise in membrane bone. Only the base of the anterior three neural arches, the base of the hemal arches of the third preural centrum, the neural and hemal arches and spines of the second preural centrum, the parhypural, the two hypural plates, and the single epural are preformed in cartilage. In contrast to most teleosts, the proximal-middle radials of the dorsal and anal fins are upright and symmetrical and their distal tips coalesce during development to form a deep band of cartilage, from which the spherical distal radials are spatially separated.  相似文献   

6.
Abstract

The two endemic species of New Zealand Limnichthys differ in several osteological characters. L. polyactis differs from L. rendahli in having a rayed dorsal margin of the opercle (cf. entire), little or no gap between the lower limb of the coracoid and the pelvis (cf. wide gap), one epural (cf. two), and narrow posterior neural and haemal spines (cf. wide spines). Comments are given on some characters in the other 10 recognised named species of Creediidae. Squamicreedia obtusa is removed from the Creediidae, and is provisionally placed in the Percophididae.  相似文献   

7.
Many members of the mullets (family Mugilidae) are very similar morphologically, hence the possibility of taxonomic misidentification. This study involved the use of skeleton structure to distinguish four species of mullets, including Cremugil crenilabis, Liza macrolepis, Moolgarda engelii, and Mugil cephalus, harvested from Aceh waters, Indonesia. The mullets samples were collected from 10 locations, and a total of 10 samples were taken randomly as representatives of each species. The skeletal sample was prepared using the dry method. The results showed the presence of 8 pairs of ribs in C. crenilabis and L. macrolepis, while M. engelii had 9, with 10 in M. cephalus. In addition, the origin of the haemal canal of C. crenilabis is at the 12th vertebrae, extends to the 23rd, while for the other three species it starts at the 10th and extends to the 23rd. In addition, C. crenilabis possesses 12 haemal canals, but the rest have 14. The haemal canal is present in the last precaudal vertebrae of all specimens, except C. crenilabis, whose epural bone in the caudal skeleton is small and located far from the preural, while a larger and distinctly attached form is observed in the rest. Furthermore, L. macrolepis possess a pair of diapophyses, which laterally extend in the 2nd vertebrae. This bone is absent in the three other species. The presence of diapophyses, the number of ribs and haemal canals and the location of the epural bone in the caudal skeleton, and the condition of frontal attachment to the sphenotic are the important characters in distinguishing the four investigated species of mullets.  相似文献   

8.
Two new species of Liparidae are described from Drake Passage (55°32·8' S, 65°54·3' W). Careproctus patagonicus differs from all other congeneric species in the following combination of characters: C 9 (1+4/4), epural and parhypural unfused to single hypural; gill slit above P base; lower pectoral lobe well developed; pectoral girdle with one ventral radial (0+0+0+1) with a central foramen; da 2·4, aAf 10·2% LS; disk 41·5% HL; some crater-like pits on posterior half of body; head and anterior part of body white. Careproctus magellanicus has the following diagnostic characters: A 46; P 24, well-developed lower pectoral lobe; scattered crater-like spots and some thumb-tack prickles on body; one suprabranchial pore; basal plate of the pectoral girdle with two fenestrae; four radials (3+1), the first with a ventral notch; HL 17·1, preD 18·5% LS. The structure of the endochondral pectoral girdle of both species is commented.  相似文献   

9.
Louis Taverne 《Geobios》1977,10(1):5-33
The osteological study of the genus ThrissopsAgassiz, 1833 (sensu stricto) from the Upper Jurassic of Germany and France allows to define the systematic position of that fossil fish within the primitive Teleosts. The general shape of the skull, the jaws, the ethmoidal area, the circumorbital bones, the fronto-parieto-supra occipital area, the parasphenoid and the opercular bones are all characters which prove that Thrissops belongs to the family Ichthyodectidae (order Ichthyodectiformes, super-order Osteoglossomorpha). However Thrissops is more primitive than the other Ichthyodectidae which are all of Cretaceous age. It possesses indeed two parietals bearing pit-lines, a premaxillary and a maxillary normally developed, a palatine and a metapterygoid without any contact, a denticulated entopterygoid, three free epurals and six uroneurals, while, in the Cretaceous Ichthyodectidae, the parietals are fused in one bone without any pit-line, the premaxillary and the maxillary are hypertrophic, the palatine touchs the metapterygoid, the entopterygoid is toothless, the epural disappear or fuse with the terminal neural arches to form supplementary neural spines, and the uroneural are only five.  相似文献   

10.
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   

11.
大黄鱼仔稚鱼脊柱、胸鳍及尾鳍骨骼系统的发育观察   总被引:4,自引:0,他引:4  
研究采用二重染色法对3-28日龄人工培育的大黄鱼Larimichthys crocea(Richardson)仔稚鱼的部分骨骼系统的发育进行观察。结果显示,仔鱼的脊索从6日龄(平均全长MTL3.9mm)开始分节,8-10日龄髓弓、脉弓先后开始发育,14日龄(MTL7.5mm)脊椎骨、髓棘、脉棘均已形成,至28日龄(MTL19.5mm)已发生骨化;大黄鱼仔鱼孵化时,胸鳍的上匙骨、匙骨、后匙骨、支鳍骨原基已形成,27日龄(MTL19.0mm)稚鱼具5块支鳍骨,鳍条发育完整;尾鳍发育以8日龄仔鱼脊索后端腹部2块尾下骨的形成开始,至14日龄仔鱼尾鳍已初具雏形,尾杆骨、尾上骨和尾下骨均发育完全,21日龄稚鱼尾下骨排列成弧状,第三与第四块尾下骨之间的缝隙增大,把尾鳍鳍条分为上下两部分,鳍条分节明显,28日龄稚鱼尾鳍尾杆骨及鳍条发生钙化。    相似文献   

12.
The ontogenetic development of caudal vertebrae and associated skeletal elements of salmonids provides information about sequence of ossification and origin of bones that can be considered as a model for other teleosts. The ossification of elements forming the caudal skeleton follows the same sequence, independent of size and age at first appearance. Dermal bones like principal caudal rays ossify earlier than chondral bones; among dermal bones, the middle principal caudal rays ossify before the ventral and dorsal ones. Among chondral bones, the ventral hypural 1 and parhypural ossify first, followed by hypural 2 and by the ventral spine of preural centrum 2. The ossification of the dorsal chondral elements starts later than that of ventral ones. Three elements participate in the formation of a caudal vertebra: paired basidorsal and basiventral arcocentra, chordacentrum, and autocentrum; appearance of cartilaginous arcocentra precedes that of the mineralized basiventral chordacentrum, and that of the perichordal ossification of the autocentrum. Each ural centrum is mainly formed by arcocentral and chordacentrum. The autocentrum is irregularly present or absent. Some ural centra are formed only by a chordacentrum. This pattern of vertebral formation characterizes basal teleosts and primitive extant teleosts such as elopomorphs, osteoglossomorphs, and salmonids. The diural caudal skeleton is redefined as having two independent ural chordacentra plus their arcocentra, or two ural chordacentra plus their autocentra and arococentra, or only two ural chordacentra. A polyural caudal skeleton is identified by more than two ural centra, variably formed as given for the diural condition. The two ural centra of primitive teleosts may result from early fusion of ural centra 1 and 2 and of ural centra 3 and 4, or 3, 4, and 5 (e.g., elopomorphs), respectively. The two centra may corespond to ural centrum 2 and 4 only (e.g., salmonids). Additionally, ural centra 1 and 3 may be lost during the evolution of teleosts. Additional ural centra form late in ontogeny in advanced salmonids, resulting in a secondary polyural caudal skeleton. The hypural, which is a haemal spine of a ural centrum, results by growth and ossification of a single basiventral ural arococentrum and its haemal spine. The proximal part of the hypural always includes part of the ventral ural arcocentrum. The uroneural is a modification of a ural neural arch, which is demonstrated by a cartilaginous precursor. The stegural of salmonids and esocids originates from only one paired cartilaginous dorsal arcocentrum that grows anteriorly by a perichondral basal ossification and an anterodorsal membranous ossification. The true epurals of teleosts are detached neural spines of preural and ural neural arches as shown by developmental series; they are homologous to the neural spines of anterior vertebrae. Free epurals without any indication of connection with the dorsal arococentra are considered herein as an advanced state of the epural. Caudal distal radials originate from the cartilaginous distal portion of neural and haemal spines of preural and ural (epurals and hypurals) vertebrae. Therefore, they result from distal growth of the cartilaginous spines and hypurals. Cartilaginous plates that support rays are the result of modifications of the plates of connective tissue at the posterior end of hypurals (e.g., between hypurals 2 and 3 in salmonids) and first preural haemal spines, or from the distal growth of cartilaginous spines (e.g., epural plates in Thymallus). Among salmonids, conditions of the caudal skeleton such as the progressive loss of cartilaginous portions of the arcocentra, the progressive fusion between the perichondral ossification of arcocentra and autocentra, the broadening of the neural spines, the enlargement and interdigitation of the stegural, and other features provide evidence that Prosopium and Thymallus are the most primitive, and that Oncorhynchus and Salmo are the most advanced salmonids respectively. This interpretation supports the current hypothesis of phylogenetic relationships of salmonids. © 1992 Wiley-Liss, Inc.  相似文献   

13.
Several studies have evaluated the effects of dietary vitamin A (VA) on the incidence of skeletal deformities during early ontogeny of fish, but little is known about its effects on bones depending on their process of ossification (dermal or chondral). We examined the incidence of skeletal deformities along development (30 and 48 dph) by double staining technique, in dermal (haemal and caudal vertebral bodies) and chondral (neural and haemal spines, epural, parahypural and hypurals) bones in Senegal sole post metamorphosed larvae fed with different dietary VA levels (37 000, 44 666, 82 666 and 203 000 UI total VA kg?1 DW) during Artemia feeding phase (6–37 dph, at 18°C). Results obtained in this study showed that dietary VA disrupted the skeletogenesis in Senegalese sole post metamorphosed larvae by increasing the incidence of skeletal deformities in the axial skeleton and caudal fin complex, which were dependent on both bone morphogenesis and ossification processes. Fish fed with the highest dietary VA content showed the highest incidence of skeletal deformities and its value increased along ontogeny. However, when we compared the incidence of deformities in skeletal structures considering their ossification process, most skeletal structures derived from chondral ossification showed a significant higher increase in deformity incidences in fish fed an excess of VA (44 666, 82 666 and 203 000 UI kg?1 DW), however within chondral bones, hypurals deformity incidence only increased in sole larvae fed Artemia highest VA content. In contrast, this dietary dose‐response effect was only noted in dermal bones from fish fed the highest dose of VA (203 000 UI kg?1 DW). In addition, the incidence of deformities in chondral bones increased even when the dietary imbalance of VA was corrected, whereas dermal bones were not affected at later ages. These results indicated that depending on the ossification process from which different skeletal structures are derived, bones might be differentially affected by high dietary VA content. Those directly originated from the connective tissue with a preliminary cartilage stage were more sensitive to dietary VA excess than those formed by intramembranous ossification.  相似文献   

14.
戴氏狼鳍鱼(Lycoptera davidi)的重新观察   总被引:9,自引:8,他引:1  
本文主要对戴氏狼鳍鱼 (Lycoptera davidi) 骨骼系统的特征进行了补充和订正.在此基础上,对狼鳍鱼属 (Lycoptera) 的特征及有关狼鳍鱼种的分类问题作了初步探讨.  相似文献   

15.
本文记述了产自山东蒙阴盆地分水岭组中原始真骨鱼类—新属、新种——宁家沟谭氏鱼(Tanichthys ningjiagouensis gen. et sp. nov.).据其形态特征,它应归入舌齿鱼超科(Hiodontoidea),并与舌齿鱼科的成员接近.其生存时代很可能为早白垩世.  相似文献   

16.
山东山旺中中新世鲤科化石   总被引:12,自引:7,他引:5  
本文记述了山旺中中新世鲤科鱼类6属9种,其中5属6种为新发现;还记述了河南始新世一新属种;订正了Barbus linchiiensis, Barbus scotti, Pseudorasbora, macrocephala和Leuciscus miocenicus的系统位置。本文认为鲤类在中国最早出现于始新世,此后鱼类区系曾发生过较大的演替。前人订为现生属的始新世、中新世鲤类化石绝大部分应为已绝灭的化石属。  相似文献   

17.
农田烟粉虱寄主植物调查初报   总被引:14,自引:2,他引:14  
2001~2002年通过调查福州、漳州农田烟粉虱寄主范围,记录农田烟粉虱寄主植物17科62种(变种).其中豆科7种、茄科6种、十字花科8种、葫芦科9种、菊科10种、苋科4种、藜科4种、旋花科2种、锦葵科2种、、大戟科2种、柳叶草科2种、蓼科1种、玄参科1种、番杏科1种、大麻科1种、免丝子科1种、伞形花科1种。农田烟粉虱寄主植物主要以蔬菜作物和农田阔叶杂草为主。  相似文献   

18.
刘文萍 《四川动物》2005,24(4):529-531
横断山区的蝶类561种,隶属于12科,208属.在12科中,种类最多的是蛱蝶科148种,其次是眼蝶科117种,灰蝶科65种,凤蝶科63种,粉蝶科60种,弄蝶科60种,蚬蝶科18种,绢蝶科12种,斑蝶科9种,环蝶科6种,喙蝶科2种,珍蝶科1种.分布于横断山区的珍稀蝴蝶有44种,其中国家Ⅰ级保护的1种,Ⅱ级保护的3种.  相似文献   

19.
An Analysis of Hamster Afferent Taste Nerve Response Functions   总被引:8,自引:3,他引:5       下载免费PDF全文
Sensitivities to moderately intense stimuli representing four taste qualities to man were determined for 79 hamster chorda tympani fibers. Some fibers were very sensitive to sucrose, sodium chloride, or hydrochloric acid, but none were very sensitive to quinine. These sensitivities were not randomly distributed among fibers: the sucrose sensitivity was separated from and negatively correlated with the other sensitivities which were associated and positively correlated with each other. Moreover, there were a limited number of sensitivity patterns: (a) fibers responding best to sucrose responded second-best to salt, less to acid, not to quinine; (b) fibers responding best to salt either responded second-best to sucrose and not to acid or quinine; or second-best to acid, less to quinine, and not to sucrose; and (c) fibers responding best to acid responded second-best to salt, more to quinine, and less to sucrose than other fibers. Therefore, if four stimuli of different taste qualities are ordered from acceptable to unacceptable, neural response functions of most hamster chorda tympani taste fibers peak at one point. Sensitivities to nine other moderately intense stimuli which vary in quality to man were also determined for 46–49 of the fibers. Sensitivities to sweet stimuli were always associated with each other and separated from sensitivities to nonsweet stimuli. Sensitivities to nonsweet stimuli were all associated with each other; however, the strongest correlations were between sensitivities to stimuli of like quality, e.g., the three acids or the two sodium salts.  相似文献   

20.
Data from 27 feeding trials conducted on growing pigs from different research institutes across India were subjected to mixed model regression analysis to derive requirements of digestible energy (DE), crude protein (CP) and essential amino acids for maintenance and body weight gains. The ranges of maintenance requirements were determined to be: DE 516 to 702 kJ/kg M0.75, CP 6.98 to 11.62, lysine 0.431 to 0.664, methionine 0.265 to 0.458, methionine + cystine 0.327 to 0.466, cystine 0.055 to 0.184, threonine 0.205 to 0.511, arginine 0.377 to 1.21, isoleucine 0.241 to 0.775, leucine 0.604 to 1.54, phenylalanine + tyrosine 0.496 to 1.33, tryptophan 0.078 to 0.213, and valine 0.330 to 0.892 g/kg M0.75, respectively for different body weight ranges. The corresponding requirements for 1 g gain in body weight were: DE 28.6 to 38.6 kJ, CP 0.27 to 0.44 g, lysine 0.0071 to 0.0126 g, methionine 0.0047 to 0.0133 g, methionine + cystine 0.0151 to 0.0261 g, cystine 0.0043 to 0.0094 g, threonine 0.0052 to 0.0165 g, arginine 0.0045 to 0.0301 g, isoleucine 0.0023 to 0.0198 g, leucine 0.0150 to 0.0447 g, phenylalanine + tyrosine 0.0091 to 0.0382 g, tryptophan 0.0005 to 0.0044 g, and valine 0.0061 to 0.0222 g. Regression equations had high R2 values (ranging from 0.50 to 0.99 for different estimates), low coefficients of variation, low variance of error estimates and the coefficients were highly significant (P < 0.001). Regressed values were used to develop feeding standards. As the new standards derived in the present study are based on a thorough analysis of a larger database than previous Indian standards, the new feeding standard seems to be more appropriate for India and other tropical countries.  相似文献   

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