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The classification of the Carassius complex (Cyprinidae) including all-female triploids, called ginbuna in Japanese, is so confused that three sympatric morphs of crucian carp in Lake Kasumigaura are categorized into two different subspecies within a species. We examined them in order to explain the coexistence of more than one subspecies and determine the founder of the triploid lineages in the crucian carp fauna in the lake. Principal component analysis proved that the three sympatric morphs had a morphometric basis distinguishable from each other. Ploidy was determined by flow cytometry which showed triploids in two morphs and diploids in the other morph. Stepwise discriminant analysis using only meristic characteristics could separate the diploids from the triploids. Phylogenetic analysis using mitochondrial DNA inferred two lineages in which one was composed of a triploid morph and the other was a diploid–triploid mixture. Disagreement between the taxonomic status and the phylogenetic status is explicable by assuming that the triploids in the Carassius complex had independent origins leading to the different subspecies. C. auratus langsdorfii appears to show genetic complexities that traditional taxonomic classification can not unravel.  © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 79 , 351–357.  相似文献   
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It was found that light accelerates the swelling of spinachchloroplasts suspended in a solution containing NaCl and Tris-HCl,and that, in about 60 min, the swollen chloroplasts begin toshrink rapidly. The volume of chloroplasts reached, on swelling,270 per cent of the original volume on the average and thenshrank to 17 per cent. The rate of swelling and the maximumvolume were affected markedly by the tonicity of NaCl. NH4Cldid not affect the volume changes, while phenazine methosulfateaccelerated the swelling remarkably. The relationship betweenphotoshrinkage and this light-induced high-amplitude swellingwas discussed. (Received April 2, 1966; )  相似文献   
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Chloroplasts suspended in phosphate buffer with PMS swelledrapidly on illumination, their volumes reaching a maximum levelwithin 5 min. Subsequently they shrank noticeably. Both swellingand subsequent shrinkage were reversible; in the former, chloroplastsswelled on illumination and shrank on turning off the light.In the latter,olume change occurred in the opposite direction.Light-induced swelling in the presence of PMS disappeared onalternating light and dark several times. Thereafter, only shrinkagewas observed. Only shrinkage took place on illumination when PMS was addedto Tris-washed, or heated chloroplasts, or when chloroplastswere suspended in phosphate buffer with other electron transportcofactors such as FMN and vitamin K3 or in acetate buffer insteadof phosphate in the presence of PMS. PMA and CCCP (low concentration)inhibited swelling with PMS. Quinacrine had no effect on volumechanges with PMS, while antimycin A and CCCP (high concentration)completely prevented both swelling and shrinkage. These suggestthat volume changes are a result of competition between swellingand shrinking activities which depend on utilization of highenergy intermediates formed by PMS-induced photochemical reactions. (Received February 18, 1970; )  相似文献   
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For coexistence, the sexual form in sexual/asexual complexes needs short-term advantages that can compensate for the two-fold disadvantage of sex. Higher mortality in the asexual form due to a higher parasite load will provide an advantage to the sexual form. In Lake Suwa, Japan, the parasite load (Metagonnimus sp.; Trematoda) of triploid gynogenetic females of Carassius auratus was significantly higher than that of diploid sexual females. In an immunoassay using healthy wild fish that were conditioned for 1 month in laboratory tanks, the nitroblue tetrazolium (NBT) immune reaction of sexual females was significantly higher than that of gynogenetic females. The NBT activity indicates the abundance of oxygen radicals from phagocytes, and hence the level of immune activity of the phagocytes. We suggest that the higher parasite load of the gynogenetic form is in part due to the lower immune activity of the phagocytes (nonspecific immune reaction) in the gynogenetic form compared to the sexual form.  相似文献   
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Abstract.  Systematic relationships among higher taxa within Chrysopidae, a large and agriculturally significant neuropteran family, are poorly understood. A molecular phylogenetic survey of Chrysopidae was performed with three nuclear genes, namely wingless (546 bp), phosphoenolpyruvate carboxykinase (483 bp), and sodium/potassium ATPase alpha subunit (410 bp). We examined 83 species in 24 genera, mainly from Japan, Eurasia and Africa. Parsimony and Bayesian analyses of combined datasets of a total of 1439 bp demonstrated that (1) monophyly of the subfamily Chrysopinae was supported but the relationship between Nothochrysinae and Apochrysinae was unclear, although the two subfamilies together may constitute the sister taxon of Chrysopinae; (2) of the three tribes examined within Chrysopinae (Ankylopterygini, Belonopterygini and Chrysopini), monophyly of Ankylopterygini and Belonopterygini was supported, but the relationships among the three remain unclear; (3) seven sub-clades in Chrysopini were indicated, namely (i) Brinckochrysa , (ii) Chrysemosa  +  Suarius , (iii) Chrysotropia  +  Nineta , (iv) Mallada  +  Chrysoperla  +  Peyerimhoffina , (v) Cunctochrysa  +  Meleoma  +  Nipponochrysa  +  Apertochrysa albolineatoides , (vi) Chrysopa  +  Plesiochrysa , and (vii) Dichochrysa  +  Apertochrysa eurydera ; and (4) most genera were monophyletic, except for Apertochrysa and Cunctochrysa , each of which was shown to have two distinct origins. Our molecular analysis allowed the assignment of several species of uncertain affinities to known genera. There was some disagreement between the molecular and previously published morphological phylogenies, but in general our results confirmed existing morphological hypotheses of evolution within the family.  相似文献   
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