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1.
Journal of Ichthyology - The three differentiated phylogenetic lineages of sharpbelly from the group Hemiculter leucisculus s.l. corresponding to clades A, B, C sensu Chen et al. (2017) have been...  相似文献   

2.
Phylogenetic analyses based on the complete nucleotide sequence of the mitochondrial 12S ribosomal RNA gene were performed for representatives of major North American cyprinid clades. These analyses resolved four monophyletic groups: (1) Western Clade, represented by Acrocheilus and Gila , (2) Creek Chub Clade, represented by Couesius, Hemitremia, Semotilus , and Margariscus , (3) Open Posterior Myodome Clade, represented by Campostoma, Phenacobius, Cyprinella, Notropis, Platygobio , and Rhinichthys , and (4) Plagopterin Clade, represented by Snyderichthys, Lepidomeda , and Meda . The overall results of these analyses refute previous hypotheses of relationships of North American Cyprinidae based on morphological data. Our analyses support recognition of Snyderichthys , formerly considered a subgenus of Gila, and indicate that the Plagopterin Clade is sister to the Creek Chub Clade. Furthermore, this analysis indicates that hypotheses of relationship between plagopterins and other Western taxa are unsupported and the Open Posterior Myodome Clade is a monophyletic group.  相似文献   

3.
在整理华缨鱼属标本时发现,1993年9月在广西壮族自治区天峨县红水河水系地下河采集到的一批标本为一个未经发表的新种,新种订名为大眼华缨鱼(Sinocrossocheilus megalophthalmus)。其下咽齿2行,可与下咽齿3行的7种华缨鱼相区别,而与属内同样具2行下咽齿的贵州华缨鱼(S.guizhouensis)、小口华缨鱼(S.microstomatus)和宽唇华缨鱼(S.labiatus)亲缘关系较近。但:(1)新种胸鳍中点上方无黑斑,背鳍分枝鳍条7,腹鳍分枝鳍条7,背鳍前鳞15—16,眼大,头长为眼径2·5—3·1倍,眼径为头宽44·7%—57·8%,吻须后伸至前后鼻孔之间或眼前缘,口角须后伸至眼前缘至眼中之间或眼中至眼后缘之间,体长为尾柄高8·9—10·7倍,头长为吻长2·5—3·7倍,可与贵州华缨鱼(胸鳍中点上方有一明显黑斑,背鳍分枝鳍条8,腹鳍分枝鳍条8,背鳍前鳞12—14,头长为眼径4·0—5·0倍,眼径为头宽16·6%—20·7%,吻须后伸不达后鼻孔后缘,口角须后伸至眼前缘,体长为尾柄高7·2—8·2倍,头长为吻长1·9—2·2倍)相区别;(2)新种背鳍前鳞15—16,侧线鳞39—40,侧线上鳞4·5—5·5,背鳍分枝鳍条7,鳃耙13,腹鳍末端伸达肛门,眼径为头宽44·7%—57·8%,可与宽唇华缨鱼(背鳍前鳞22,侧线鳞42—45,侧线上鳞6·5,背鳍分枝鳍条8,鳃耙10,腹鳍末端不达肛门,眼径为头宽23·3%—30·0%)相区别;(3)新种与同水系的小口华缨鱼在鳍条数、侧线鳞、体色、斑纹等方面最为相似,但新种围尾柄鳞14/16,眼大,头长为眼径2·5—3·1倍,腹鳍末端伸达肛门,口角须后伸至眼前缘至眼中之间或眼中至眼后缘之间,吻皮边缘深裂成小穗,背鳍起点距吻端较距尾鳍基为近,背鳍长大于头长,体长为尾柄长4·8—5·9倍,头长为吻长2·5—3·7倍,尾柄长为尾柄高1·6—2·1倍,可与之(围尾柄鳞12,眼小,头为眼径4·4—4·6倍,腹鳍末端不达肛门,口角须伸达眼下方,吻皮边缘不开裂或开裂不明显,背鳍起点距吻端等于距尾鳍基,背鳍条约等于头长,体长为尾柄长6·1—6·4倍,头长为吻长2·1—2·4倍,尾柄长为尾柄高1·4—1·5倍)相区别。  相似文献   

4.
本文记述了云南澜沧江水系景洪流域段(100°47'43″E,22°0'28″N)鳘条Hemiculter leucisculus(Basilewsky,1855)鳃丝上寄生指环虫属Dactylogyrus 2新种,以采集地命名为版纳指环虫Dactylogyrus bannaensis sp.nov.和景洪指环虫D.jinghongensis sp.nov.。版纳指环虫和景洪指环虫均为双联结片虫,基于后吸器,尤其是中央大钩、边缘小钩和交接器的形态学特征,鉴定为指环虫属科学上2新种。版纳指环虫交接器的形态有别于记录种船茎指环虫D.nilkolskyi Gussev,1955,版纳指环虫的交接管呈长带状,延伸至虫体左侧边缘阴道口处,末端微弯;感染率100%(40/40)。寄生于同一宿主的景洪指环虫,其交接器的形态有别于记录种红鲌指环虫D.erythroculteris和锥花指环虫D.pannosus,景洪指环虫的交接器呈彩虹状,交接管的一端基部膨大成漏斗状,另一端折叠;支持器"V"形,且中间包绕交接管;感染率100%(40/40)。  相似文献   

5.
6.
The phylogenetic relationships of five amphipod species of the genus Gummarus: G. oceanicus, G. locusta, G. salinus, G. zaddachi and G. duebeni are presented based on starch gel electrophoresis of 12 enzymes determined by 17 loci. The five species separate into three groups: G. locusta and G. duebeni each represent a distinct group while G. oceanicus, G. salinus and G. zaddachi together form a third group. This grouping results when the number of diagnostic loci, as well as when genetic distance between species pairs, are considered. The results compare well with morphological and, to some extent, ecological data.  相似文献   

7.
Polynucleotide relationships among selected Vibrio species were examined by means of deoxyribonucleic acid (DNA) reassociation reactions and chromatography on hydroxyapatite. Relative levels of intraspecific DNA duplex formation (V. cholerae-V. cholerae and V. parahaemolyticus-V. parahaemolyticus) were found to be high at 60 C (>80%), and only minimally reduced at 75 C. Interspecific DNA duplexes between V. cholerae DNA and that of the non-cholera vibrios also exhibited high relative levels of formation at 60 C (>80%) and, with one exception, were only slightly reduced at 75 C. The thermal stability of these duplexes formed at 60 or 75 C was virtually identical to that of homologous V. cholerae DNA duplexes. The degree of reassociation and the thermal stability of V. cholerae-non-cholera vibrio DNA duplexes suggests relatively little evolutionary divergence in these organisms. In all other interspecific DNA reassociation reactions, only low levels of DNA duplex formation were noted at 60 C (<25%), and these were drastically reduced (>50%) at 75 C. The degree of nucleotide sequence divergence indicated by these reactions suggests that these Vibrio species are not significantly related to V. cholerae or V. parahaemolyticus. Reassociation reactions between V. cholerae DNA and the DNA of V. parahaemolyticus indicated these species were not significantly related to each other.  相似文献   

8.
A new species of the subfamily Barbinae, Tor yingjiangensis, is recognized from Yunnan province, China. It can be distinguished from other Tor species by the following combination of characters: last simple dorsal-fin ray osseous and non-serrated; no forward directed predorsal procumbent spine; head length considerably longer than body depth; no tubercles on the snout or sides of the face; 18–20 gill rakers on the outside of first gill arch; 24–26 lateral line scales; median lobe of lower lip short, its posterior margin truncate, not extending to the vertical across the inner corners of the mouth; and the condition of the lower lip consistent in individuals of different sizes. The new species has been misidentified previously as Tor putitora (Hamilton, F. 1822. An account of the fishes found in the River Ganges and its Branches. Edinburgh & London. 405 pp), which occurs in the Ganges and Indus River basins. The new species can easily be distinguished from T. putitora by having 3–3.5 (vs. 2.5) scales from lateral line to pelvic-fin origin, shorter caudal peduncle length (13.0% vs. 17.2% of standard length), lesser body depth (26.4% vs. 24.0% of standard length) and longer caudal peduncle depth (12.0% vs. 10.9% of standard length), no longitudinal stripe present along side of body, and eyes visible in ventral view of head.  相似文献   

9.
The esterase patterns of sixteen strains from four species in the saltans subgroup were analyzed using polyacrylamide gel electrophoresis. Thirty-four esterase bands were detected. By using and naphthyl acetates as substrates, they were classified in 18 -esterases (they hydrolyse the -naphtyl substrate), 15 -esterases (they hydrolyse the -naphtyl substrate) and 1 /-esterase (it hydrolyses the and -naphtyl substrates). Among the -esterases, three were detected exclusively in males. Malathion, Eserine and pCMB were used as inhibitors in order to characterize biochemically the esterases. The results indicated the presence of cholinesterases, carboxylesterases and acetylesterases. The degree of mobility of the bands in the gels, their specificity to and naphthyl acetates and the results of the inhibition tests allowed us to recognize tentatively nine genetic loci. Phylogenetic relationships among species inferred on the basis of the esterase patterns by PAUP 4.0b8, with neighbor-joining search and a bootstrap analysis showed that, although the four species are closely related, D. septentriosaltans, D. saltans and D. austrosaltans are closer to each other than to D. prosaltans. These results showed to be consistent with phylogenetic relationships previously inferred from inversion polymorphism.  相似文献   

10.
11.
Lapsamita maddisoni gen. et sp. nov. is described from Bahia, Brazil. The presence of palpal claws in females, long ventral spines on front tibiae and metatarsi and long retrolateral tibial apophyses in male palps suggested that the species was closely related to or even nested within Soesiladeepakius Makhan, 2007. To evaluate its phylogenetic position, a cladistic analysis was carried out using a data matrix comprising 24 morphological characters, scored for 13 taxa. The analysis showed L. maddisoni as the sister group of Soesiladeepakius, supporting the proposal of the new genus. Character evolution is discussed and compared to a previous study on the group.  相似文献   

12.
中鲤亚属的分支系统学分析   总被引:2,自引:0,他引:2  
基于外部形态特征和内部骨骼特征对鲤科鲤属中鲤亚属进行了分支系统学分析,内群包括中鲤亚属的全部5种和鲤亚属的2种鱼类,外群采用乌原鲤。在鲤属鱼类和外群间共有48个性状存在变化。系统发育分析采用PAUP^*软件的Parsimony和Bootstrap两种方式的Branch-and-Bound算法,排除不能极化的特征和特有离征之后,还有28个特征可用,由这28个特征可得到唯一的系统树,树长69,一致性系数0.7246,排除无用特征的一致性系数0.6122,保留系数0.6346。由5种中鲤组成的中鲤亚属明显不构成一个单系群。结果表明:中鲤亚属是一个复系群,该类元应该被撤销。  相似文献   

13.
2003年4月,于怒江二级支流镇康县境内的大叉河中采获一批墨头鱼属(Garra)鱼类标本,经鉴定为一新种,命名为怒江墨头鱼(G. nujiangensis Chen and Yang, sp. nov.)。该新种主要鉴别特征:围尾柄鳞12~14;侧线鳞48~50;在小个体中有一对微小的吻须;背鳍分支鳍条 8~9;侧线上鳞5~6,侧线下鳞3~4;体高小于头长;臀鳍起点处的小于眼后至吻端的距离;腹鳍前长为体长的50.0%~53.7%;肛门前长为体长的58.9%~63.9%;体宽为体长的 16.7%~19.6%;体高为体长的19.2%~22.6%。本研究证实,在缺须的墨头鱼属的一些物种中,如高体墨头鱼(G. alticorpora)和怒江墨头鱼(G. nujiangensis),其幼体中往往具有一对很小的吻须。  相似文献   

14.
E Zhang  Yi-Yu Chen 《Hydrobiologia》2004,527(1):25-33
Qianlabeo striatus gen. et sp. nov. is described from a stream tributary to the Beipan Jiang of the upper Zhu Jiang (Pearl River) drainage in Matou, Anshun County, Guizhou Province, China. This monotypic genus is mainly characterized by its oromadibular morphology, namely an upper lip only present in and fully adnate to the side of the upper jaw, not covered by the pendulous rostral fold; the median portion of the upper jaw lacking an upper lip but bearing a thin, flexible and cornified cutting edge that is fully covered by the pendulous rostral fold; a postlabial groove prolonged, extended anteromedially close to the anteromost point of the midline of the lower lip but not to meet with its counterpart. The type species of this genus, Q. striatus has a longitudinal dark stripe along the side of the body.  相似文献   

15.
新种长鳍异华鲮Parasinilabeo longiventralis采自中国南部广西省富川县境内珠江水系的一条支流——贺江。新种与异华鲮属(Parasinilabeo)内的其他种的主要区别特征是:口角须长为吻须长的78.3%—90.4%; 腹鳍长度为腹鳍起点和臀鳍起点间的距离的83.7%—89.4%;在侧线鳞的后方有一宽的褐色纵条纹;体上有不规则的斑点。  相似文献   

16.
本研究报道单肠目Rhabdocoela斯库台科Scutariellidae斯库台涡虫属Scutariella新种:中国斯库台涡虫,新种Scutariella sinensis sp.nov.,对其进行了形态学、分子系统学等研究。新种的主要鉴别特征:(1)二支卵黄腺在背部两侧沿肠管分布,在近肠后部愈合,整体呈"U"型;(2)生殖孔位于肠前端腹侧;(3)咽腺丰富,位于咽肠交界处的两侧;(4)精巢、卵巢位于肠道前1/3腹侧。新种的18S rDNA和28S rDNA分子系统发生研究首次提供了切头类斯库台科的分子数据,确定切头亚目Temnocephalida的分类地位及该亚目与吸虫类的进化关系。  相似文献   

17.
The Gobioninae are a group of morphologically and ecologically diverse Eurasian freshwater cyprinid fishes. The intergeneric relationships of this group are unresolved and the possible monophyly of this subfamily remains to be established. We used complete mitochondrial cytochrome b gene sequences from most genera within the gobionine group, in addition to a selection of cyprinid outgroups, to investigate the possible monophyly of this group and resolve the interrelationships within the group. Our results support the monophyly of the Gobioninae and identify four monophyletic groups within the subfamily; the Hemibarbus group, the Sarcocheilichthys group, the Gobio group, and the Pseudogobio group. The morphologically aberrant genera Gobiobotia, Xenophysogobio and Gobiocypris are included in the Gobioninae, with the latter a sister group of Gnathopogon.  相似文献   

18.
ABSTRACT Horseflies of the Tabanus cordiger species group from Korea is revised taxonomically. A total of four species are arranged herein: T. divulsus sp. nov., T. fulvimedioides, T. kinoshitai and T. loukashkini. A key to discriminate species, annotated check lists of domestic records, and collection data for each species are provided.  相似文献   

19.
The genus Oreocharis as circumscribed here consists of 27 species including 5 varieties, of which 5 species and 4 varieties are described as new in the present paper. In the work analysed were the external morphology and geographic distribution and examined under SEM were pollen exine of 22 species and seed coat of 16 species. As a result, three types of the corolla, two types of the anther, three types of the pollen exine and three types of the seed coat are distinguished here in the paper. It is discovered that the corolla in the genus is relatively stable, though diverse, and highly correlated with the characters of pollen grains and seeds. The corolla clearly bilabiate but constricted at the throat, occurring in O. auricula, O. cordatula, O. aurantiaca, etc., for an example, is correlated with smooth, reticulate pollen exine and partial tectum and the reticulate and smooth seed coat. For this reason the subdivision of the genus in the paper is mainly based on the characters of the corolla, but combined with those of the anther, pollen and seed coat. The genus is divided into four sections in the present classification. Dasydesmus Craib, based on a single species. O. bodinieri, is reduced here, and the reasons are given. The genus is distributed mainly in the subtropics, and less frequently in the tropics, of China south of 32.5°N and east of 98.5°E, with only two species beyond the border, O. hirsuta in Thailand (only a single locality in Chiengmai) and O. aurea also found in north Vietnam (see Fig. 1, Table 3). Sect. 1. Stomactin (Clarke) Fritsch. Corolla urceolate-tubular, constricted at the throat, with limb distinctly bilabiate; anthers broad-oblong; seed coat reticulate, smooth, rarely minutely tuberculate; pollen exine fine-reticulate, tectum partial and smooth, luminae slightly unequal in size. Sect. 2. Orthanthera K. Y. Pan Corolla campanulate or campanulate-tubular; anthers broad-oblong; seed coat reticulate, muri smooth, rarely spiny-processed; pollen exine fine-reticulate, with partial and smooth tectum and luminae slightly unequal in size, rarely exine insular and fine-tuberculate, tectum perforate. Setc. 3. Oreocharis Corolla thin-tubular; anthers broad-oblong; seed coat densely spinyprocessed, rarely fine-tuberculate; pollen exine insular, densely spiny-processed, rarely finereticulate and smooth, luminae unequal in size. Sect. 4. Platyanthera K. Y. Pan Corolla campanulate; anthers hippocrepiform; seed coat densely spiny-processed; pollen exine fine-reticulate, tectum perforate, luminae small, nearly equal in size. In the section Stomactin, although the constriction of corolla at its throat is a specialized character, the characters of seed coat, pollen grains and anthers are apparently primitive. Therefore it may be said at least that more primitive characters are preserved in the section. In the section Oreocharis, on the contrary, the characters of corolla, seed coat and pollen exine are all advanced. And in the section Platyanthera, the seed coat, pollen (with perforate tectum) and anthers have developed rather specialized characters.  相似文献   

20.
Delimiting species in facultatively selfing taxa is a challenging problem of which the terrestrial pulmonate snail genus Rumina is a good example. These snails have a mixed breeding system and show a high degree of shell and color variation. Three nominal species (R. decollata, R. saharica and R. paivae) and two color morphs within R. decollata (dark and light) are currently recognized. The present study aims at evaluating to what extent these entities reflect evolutionary diverging taxonomic units, rather than fixed polymorphisms due to sustained selfing. Therefore, a phylogenetic analysis of nuclear (ITS1, ITS2) and mitochondrial DNA (COI, CytB, 12S rDNA, 16S rDNA) sequences was performed. Putative species in Rumina, inferred from the mitochondrial DNA phylogeny, were compared with those proposed on the basis of the COI gene by (1) DNA barcoding gap analysis, (2) Automatic Barcode Gap Discovery, (3) the species delimitation plug-in of the Geneious software, (4) the Genealogical Sorting Index, and (5) the General Mixed Yule Coalescent model. It is shown that these methods produce a variety of different species hypotheses and as such one may wonder to what extent species delimitation methods are really useful. With respect to Rumina, the data suggest at least seven species, one corresponding to R. saharica and six that are currently grouped under the name R. decollata. The species-level status of R. paivae is rejected.  相似文献   

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