Comparative electrophoretic studies of muscle and eye lens proteins in freshwater fish of Iraq

Muscle myogens and eye lens proteins have been studied in ten species of freshwater fish from Iraq. The electrophoretic analysis revealed that the muscle myogens can be considered as a good taxonomic criterion to differentiate the family Mugilidae from the Cyprinodontidae and Cyprinidae, but not between the families Poeciliidae and Cyprinodontidae. Within the Cyprinidae the muscle myogens can be used to diferentiate Barbus grypus from the remaining species of this family. Eye lens proteins are not considered a good taxonomic criterion to differentiate the members of the four families studied, but can distinguish B. belawayei and B. grypus from the other Cyprinid species.     

Phenotypes of Phosphoglucose isomerase,phosphoglucose mutase and general protein in some freshwater molluscs from Basrah,Iraq

Electrophoretic variants of phosphoglucose isomerase (EC.5.3.1.9) and phosphoglucose mutase (EC.2.7.5.1) have been studied in eight species of freshwater molluscs. Two phenotypes of phosphoglucose isomerase were observed in Melanopsis nodosa and one phenotype was observed in the rest of the species. One phenotype of phosphoglucose mutase was observed in all the species of molluscs studied. Phosphoglucose isomerase is inferred to be a dimer encoded at a single polymorphic locus in Melanoides nodosa. There are two alleles at this locus. Phosphoglucose mutase is inferred to be a monomer encoded at a single monomorphic locus in all species. The electrophoretic analysis revealed that phosphoglucose isomerase enzyme cannot be considered a good taxonomic criterion to differentiate the different members of the six families studied but, on the other hand, it is considered a good taxonomic criterion to differentiate Melanopsis nodosa and Theodoxus jordani. Phosphoglucose mutase is considered a good taxonomic criterion to differentiate the family Melanidae from the remaining five families studied. General protein can be considered a good taxonomic criterion to differentiate the family Corbicullidae from Melanidae, Viviparidae and Neritidae but, on the other hand, it seems to be a less useful taxonomic criterion to differentiate between the Viviparidae and Neritidae.     

A study on phosphoglucose isomerase enzyme in some elasmobranch fishes collected from Khor Al-Zubair, north west of the Arabian Gulf, Iraq

Tissue extracts of skeletal muscle, brain, gills, liver, kidney, heart, eye and spleen were electrophoretically examined for phosphoglucose isomerase (EC 5.3.1.9) activity in five species of elasmobranch fishes. Two phosphoglucose isomerases (PGI) with different specification have been found in all groups of elasmobranch fishes studied. PGI proved to be a good taxonomic criterion to differentiate members of the families Sphyrindae and Dasyatidae from the other remaining elasmobranch families. PGI appears to be controlled by duplicated genes as in other teleostean fishes.     

Phosphoglucose isomerase isozymes in teleostean fishes from the Arabian Gulf

Two phosphoglucose isomerases (PGI) with different electrophoretic mobilities have been found in all groups of teleostean fishes studied, with the exception of the Clupeomorpha. PGI proved to be a good taxonomic criterion to differentiate members of the Nemipteridae, Sciaenidae, Platycephalidae and Stromateidae from the other teleost families.     

Diversity of settlement-stage reef fishes captured by light-trap in a tropical south-west Atlantic Ocean coastal reef system

This study reports the results of 5 years of monitoring reef fish post-larvae using light traps in the Bay of Tamandaré, north-east Brazil. An annotated checklist of pre-settlement fish species, their frequency of occurrence and taxonomic characteristics are provided. In total, 4,422 post-larval fishes belonging to 36 families, 56 genera and 76 species were captured. The most species-rich families were Carangidae (7), Lutjanidae (6) and Pomacentridae (4), while the families Gerreidae (30.47%), Holocentridae (16.54%), Blenniidae (12.01%), Labrisomidae (8.36%), Lutjanidae (8.29%) and Acanthuridae (5.95%) were the most abundant. This is the first study of the taxonomic diversity and assemblage structure of settlement-stage reef fishes in the tropical south-west Atlantic Ocean. Although a few common species were not captured due to selectivity of light traps, the composition and taxonomic diversity of this first collection suggests that light traps are useful for studies of the early life history of a wide range of pre-settlement reef fishes.     

Carp myogens of white and red muscles. Gross isolation on sephadex columns of the low-molecular-weight components and examination of their participation in anaerobic glycogenolysis

1. The combined low-molecular-weight protein components of the myogens from carp white and red muscles [about 30% (w/w) of the myogen proteins] have been isolated by gel filtration on Sephadex G-75 columns. 2. The presence in this fraction from myogen of white muscle of the three main electrophoretic components previously isolated has been confirmed, and the low molecular weight of the fourth component has been definitely established. 3. The exclusive presence of this fourth component in the myogen of red muscle, apart from myoglobin, has also been demonstrated. 4. Glycogenolysis experiments in vitro have shown that the low-molecular-weight protein fraction from carp myogen does not contain enzymes from the Embden–Meyerhof chain.     

Phosphoglucose isomerase and phosphoglucose mutase isozymes in some freshwater fishes from Basrah,Iraq

Two phosphoglucose isomerases and one phosphoglucose mutase with different specificities have been found in all groups of teleostean fishes studied. PGI and PGM proved to be good taxonomic criteria to differentiate members of the families Cyprinidae and Mugilidae from the other teleost families.     

Carp myogens of white and red muscles. General composition and isolation of low-molecular-weight components of abnormal amino acid composition

1. The general composition of the carp myogens of white and red muscles was examined by electrophoresis and ultracentrifugation. 2. Eight and nine peaks were found in the electrophoretic analysis at pH7·3 and I0·075 of white and red muscle respectively. Lowering of the pH to 5 or 6 did not increase the number of peaks. The electrophoretic pattern of white-muscle myogen was remarkably different from that of red-muscle myogen, though ultracentrifugal analyses of the both types of myogen gave similar diagrams, in which about one-third of the total myogen sedimented slowly. 3. The pH–mobility curves of the myogen of white muscle indicated that the net charges of the components 2, 3 and 5 vary only slightly within the pH range 7·3–5·4, suggesting that their histidine content is very low. 4. The slow-sedimenting fraction of white-muscle myogen was isolated in fairly good yield by ammonium sulphate fractionation, by taking advantage of their high salting-out range, and the fraction was shown to be composed mainly of components 2, 3 and 5. 5. The same method of fractionation was applied to red-muscle myogen and the absence of the three components was confirmed. These results bring to light a new difference between the two types of fish muscle.     

黑线姬鼠华北亚种与长江亚种几项生化指标的比较观察

黑线姬鼠(Apodemus agrarius Pallas)在我国分布广泛,是大部分地区的主要农田害鼠,它传播多种疾病,是流行性出血热病毒的主要携带者。国内外学者对我国黑线姬鼠的分类、分布、数量变动、生活习性等进行过一些研究,但对黑线姬鼠许多生化指标的研究尚未见报道。     

Study of the soluble white muscle tissue proteins from fifteen Sparidae species

Soluble proteins of white skeletal muscle tissue of 15 species of Sparidae were analysed. Species-specific electrophoretic and isoelectric focusing patterns were found. Some bands exhibited the same mobility at genus level or at subfamily level, others differed significantly.
Considerable similarity was observed in the species of the genera Spams, Pagellus and Diplodus . Significant differences in the protein bands were noted between the contained subfamilies Denticinae, Sparinae and Boopsinae, confirming the existence of three separate phyletic lines within the family Sparidae.
This study has shown that in these species there is a similarity between classifications based on morphological data and those derived from biochemical studies.
Variation within species can be corrected for by carrying out multiple inter-specific comparisons and determining the variance of the similarity coefficients. Closely related species have similar patterns and, thus, higher similarity coefficients.
The discrepancy in similarity matrices based on morphology and white skeletal muscle tissue proteins of sea bream species shows that electrophoretic methods provide additional information relevant to the systematics of fishes.
Further work on comparison on soluble red muscle proteins of these species is proposed.     

Relationships between four novel ceratomyxid parasites from the gall bladders of labrid fishes from Heron Island, Queensland, Australia

Ceratomyxid parasites from the gall bladder of fishes from the family Labridae were examined for their taxonomic identity and their relatedness to other species of myxozoans. This paper describes four novel species Ceratomyxa choerodonae n. sp. from Choerodon cyanodus; Ceratomyxa cheilinae n. sp. from Cheilinus chlorourus; Ceratomyxa oxycheilinae n. sp. from Oxycheilinus digramma; and Ceratomyxa thalassomae n. sp. from Thalassoma lunare. Each species is characterised morphologically and small subunit (18 S) rDNA sequences were used in molecular phylogenetic analyses. Comparison of the small subunit rDNA sequences revealed four distinct species even though morphological differences indicated the presence of only two morphologically distinctive spore types. Phylogenetic analyses revealed that the ceratomyxids from labrid fishes did not form a clade to the exclusion of all other myxosporeans and provides evidence that host relatedness is not a good character to discriminate between species within the genus Ceratomyxa.     

Temporal and spatial variability of pelagic wild fish assemblages around Atlantic bluefin tuna Thunnus thynnus farms in the eastern Adriatic Sea

The abundance and size structure of wild fishes aggregated around the sea‐cages of two commercial Thunnus thynnus farms, including control locations, were assessed and compared over a 1 year period. The T. thynnus farms were located in the eastern Adriatic Sea, offshore of the islands of Ugljan and Bra?. Fish assemblages were evaluated through visual census using scuba at 2 month intervals at two sites within each farm. The data suggest that wild fish assemblages at the study sites differed greatly; 20 species occurred at the Ugljan farm and 17 at the Bra? farm, while only seven species were observed at the control locations. The abundance and diversity of wild fish assemblages were greater at the farms in comparison to control locations. The most abundant families were Sparidae and Belonidae (>80% of aggregated fishes). At both farms, the abundance and diversity of wild fishes were highest during summer, while diversity was lowest in winter and was mainly characterized by schools of bogue Boops boops and garfish Belone belone. Variability was also detected in spatial assemblages between farms; B. boops and B. belone were the most abundant species for the overall study at the Bra? farm, while B. belone and saddled bream Oblada melanura were the most abundant at the Ugljan farm. The settlement also played a significant role in farm‐associated fish assemblages, as both juveniles and advanced juveniles were common residents at farms. The majority of species which settled at the farms belonged to the sparids. Results indicate that aggregations of wild fishes at T. thynnus farms are persistent year‐round, though the assemblage compositions and size structures of dominant species vary in respect to location and season.     

Oocyte morphology of several mesopelagic fishes in connection with their taxonomic status and habitat conditions

The inner structure of oocytes was studied in 9 species of mesopelagic fish from the Myctophidae, Melamphaidae, Bathylagidae and Platytroctidae families. It was revealed that species of the same family (Myctophidae) differed less in oocyte structure than species from different families. Within the limits of subfamilies the myctophid fishes had the maximum similarity in their oocyte structure. It was established, that oocytes of fishes of different families differ by the size of vacuoles and yolk granules, and by their localization in cytoplasm.     

以演化时间为新增指标构建真菌分类系统

随着分子系统发育研究的普及,真菌各分类类群逐渐被修订为单系发生类群,通常结合形态学特征为代表的表型特征（“单系+表型特征”）对不同的分类等级命名是最为普遍的方法。历史上存在的大量多系名称被逐步修订、补充和完善,各个不同等级类群的分类系统变得更加合理、客观和趋于自然,这是分类学进程中巨大的进步。然而系统发育重建所揭示的单系类群并没有相应的标准来对应于纲目科属等种上分类等级,所以并不能直接转换为分类系统,且在分类实践中,由于不同分类学家在决定各个单系类群对应的分类等级时采用的尺度不同、依据不一,严重影响分类系统的科学性和稳定性。随着分子钟分析方法的出现,实现了对现生生物类群演化时间的估算,所以在系统发育、表型特征研究的基础上,把演化时间作为真菌分类的新增指标来划分和命名种上分类等级的方法（“单系+表型特征+演化时间”）得以应用。本文回顾了首次利用这种方法重建蘑菇属分类系统的工作,目前研究所揭示的担子菌门和子囊菌门从门至科各分类等级的演化时间范围,及利用演化时间为新增指标在分类命名中的应用;分析了影响演化时间估算可靠性的关键因素及对策。我们认为在构建分类系统的研究中增加演化时间指标,使新分类系统体现类群进化过程中的时间维度,能更全面反映类群的进化历程,促进分类系统的科学性和稳定性。     

Phylogenetic relationships of some common Indo-Pacific snappers (Perciformes: Lutjanidae) based on mitochondrial DNA sequences, with comments on the taxonomic position of the Caesioninae

The phylogenetic relationships of 27 species of common Indo-Pacific snappers (Lutjanidae) were explored using the 16S ribosomal RNA and cytochrome b mitochondrial genes with minimum evolution, maximum parsimony, maximum likelihood and Bayesian inference analyses. Included were species representing four subfamilies, the Caesioninae, Etelinae, Paradicichthyinae, and Lutjaninae. Members of the closely related families Haemulidae, Lethrinidae, Nemipteridae and Sparidae, were included for outgroup comparisons and to explore the relationships between the Haemuloidea, Lutjanoidea and Sparoidea. Monophyly of the Lutjanidae was resolved. The Caesioninae was nested within the Lutjaninae, supporting the recent view that the Caesionidae should be treated as a synonym of the Lutjanidae. The subfamilies Etelinae and Paradicichthyinae were resolved as sister taxa to the remainder of the Lutjanidae, which corroborates previous cladistic analyses conducted to determine relationships of lutjanid subfamilies. Bayesian inference and maximum likelihood analyses suggest that Macolor is the sister taxon to the Caesioninae and may represent a transitional form between the Lutjaninae and Caesioninae. Three species of Western Atlantic lutjanids, Lutjanus campechanus, L. synagris, and Rhomboplites aurorubens, were included in the analyses to examine their relationships to Indo-Pacific species; they formed a well-supported clade nested within Pacific lutjanines suggesting that Atlantic species of Lutjaninae are derived from an Indo-Pacific lineage. Results of our molecular phylogenetic analyses are congruent with the general morphology and external colouration of the resolved groups of species of Lutjanus. The "black spot" complex containing L. fulviflamma, L. monostigma, and L. russelli was resolved with strong support, and had L. carponotatus nested within. The morphology of L. carponotatus suggests a close relationship to this group, and the lack of the black spot near the lateral line below the soft dorsal fin is possibly a secondary loss. As expected, the "blue-lined" species, L. kasmira and L. quinquelineatus, formed a strongly supported clade. Lutjanus bohar and L. gibbus, both distinctly red, long-lived fish that often accumulate large quantities of ciguatera toxin in their tissues, were resolved as sister taxa.     

通过红色名录评估研究中国内陆鱼类受威胁现状及其成因

根据已有的基础资料, 采用IUCN评估等级和标准, 对中国目前已鉴定的1,443种内陆鱼类受威胁现状进行了评估。评估结果显示, 1,443种内陆鱼类中, 灭绝3种、区域灭绝1种、极危65种、濒危101种、易危129种、近危101种、无危454种和数据缺乏589种。同已有的IUCN评估结果相比, 本次被评估的物种数目多, 受威胁物种大幅度增加, 其数目达295种, 占已知中国内陆鱼类总数的20.44%, 低于全球平均值(29%)。属于灭绝等级的鱼类是大鳞白鱼(Anabarilius macrolepis)、异龙鲤(Cyprinus yilongensis)和茶卡高原鳅(Triplophysa cakaensis); 属于区域灭绝等级的鱼类是长颌北鲑(Stenodus nelma)。鲤科是受威胁物种数最多的科, 其中裂腹鱼亚科和鲤亚科的种类受威胁程度最高。长江上游和珠江上游受威胁物种最多, 是受威胁最严重的地区。中国内陆鱼类受威胁的主要因素为河流筑坝、生境退化或丧失、酷渔滥捕和引进外来种。列入数据缺乏等级的鱼类较多, 占中国内陆鱼类的40.82%, 表明对中国内陆鱼类物种多样性了解不充分, 需要加强野外调查以积累基础资料。     

尖塘鳢属鱼类线粒体12SrRNA基因序列分析

利用PCR技术扩增和测序了线纹尖塘鳢、云斑尖塘鳢和海丰沙塘鳢线粒体12SrRNA基因,结合从GenBank中下载的部分同源序列,共分析了5种鱼类的系统发育关系。在Kimura2-parameter模型构建的邻接树中,原产泰国的云斑尖塘鳢与原产澳州线纹尖塘鳢均为单系类群,二者为亲缘关系最为密切的姐妹群,海丰沙塘鳢与其它群体的亲缘关系较远,支持将尖塘鳢属从塘鳢属中分出的传统分类处理。尖塘鳢属内云斑尖塘鳢和线纹尖塘鳢鱼类种内DNA序列无差异,而种间差异明显,表明线粒体12SrRNA基因可作为塘鳢科鱼类种类鉴定的良好分子标记。