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ABSTRACT. The SSUrDNA and the ITS of different microsporidia from eight fishes, four insects and a shrimp were amplified and digested with restriction enzymes. The generated riboprints suggest a close evolutionary relationship between Glugea americanus and Spraguea lophii suggesting that Glugea americanus should be renamed Spraguea americanus and that the tissue infected and host origin should be considered of greater taxonomic importance for defining a genus than previously considered. Phylogenetic analysis of the riboprints demonstrates an unidentified microsporidium from a bumper fish ( Chloroscombrus chrysurus ) is related although not identical to Microgemma oviodea , a parasite from red band fish. We were also able to distinguish between Glugea anomala and Glugea atherinae and Glugea stephani but were not able to differenciate among the latter two. Insects isolates, Nosema costelytrae, N. bombycis, N. trichoplusiae, Nosema sp. and a shrimp isolate, Agmasoma penaei , are not related to the fish isolates.  相似文献   
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SUMMARY. 1. Laboratory and field data indicate that Cloeon triangulifer McDunnough has at least three generations per year in White Clay Creek (Pennsylvania, U.S.A.).
2. The duration of the egg stage ranged from 5 days at 30°C to about 90 days at 10°C.
3. Larvae completed development (i.e. first instar to adult) in 27 days at 25°C, 45 days at 20°C, and 179 days at 10°C on an algal diet dominated by diatoms.
4. Larvae reared on hickory leaves completed development in 30 days at 25°C but died prior to metamorphosis at 10, 15 and 20°C.
5. Adult size (i.e. body length, wing length and dry mass) and fecundity were inversely related to rearing temperature for all laboratory and field experiments.
6. The significant interaction of food quality and temperature suggest that these factors may be important in understanding geographic variation in the life history of C. triangulifer.  相似文献   
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This paper examines the variability of the genital characters ofHelix pomatia and H. lucorum. Some of these characters are commonlyused to distinguish the two closely related species. Variationswithin and between populations are also investigated. The highvariability of these characters can frequently lead to identificationerrors, especially in eastern Europe. Correct identificationof these edible snails is also of commercial importance, differentspecies having a different price. The reciprocal nature of themale parts of the genitalia and the bursa stalk and diverticulumcomplex is pointed out. A possible function of the diverticulumis suggested on the basis of size relations between genitalsystem features. (Received 12 August 1999; accepted 11 April 2000)  相似文献   
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ABSTRACT.
  • 1 Hoplothrips pedicularius (Haliday) (Thysanoptera: Phlaeothripidae), a tubuliferan thrips in which males possess greatly enlarged forelegs, lives in colonies on Stereum fungus.
  • 2 Females oviposit onto communal egg masses, and males fight by grasping and stabbing with their forelegs in territorial defence of oviposition areas. Prolonged escalated fights occur between males who are of similar size.
  • 3 Larger males usually win fights and become dominant at the oviposition area. Dominant males secure 80% of matings, and mate most frequently during oviposition periods, with an ovipositing female.
  • 4 Smaller, subordinate males avoid fights and attempt to 'sneak’copulations. However, they occasionally challenge the dominant male. Challenges tend to follow copulations by the subordinate male and occur more frequently between males who are of similar size.
  • 5 Subordinate males who eventually leave the oviposition area are larger than those who remain, have frequently challenged the dominant male, and have more frequently been stabbed.
  • 6 Sexual dimorphism in thrips is associated with gregariousness, claustral habitats, female-biased sex ratios, and male winglessness. In thrips genera in which males exhibit foreleg armature, males are larger relative to females. The ecological circumstances promoting sexual dimorphism and male fighting in spatially-structured populations are discussed.
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Pyraloidea, one of the largest superfamilies of Lepidoptera, comprise more than 15 684 described species worldwide, including important pests, biological control agents and experimental models. Understanding of pyraloid phylogeny, the basis for a predictive classification, is currently provisional. We present the most detailed molecular estimate of relationships to date across the subfamilies of Pyraloidea, and assess its concordance with previous morphology‐based hypotheses. We sequenced up to five nuclear genes, totalling 6633 bp, in each of 42 pyraloids spanning both families and 18 of the 21 subfamilies, plus up to 14 additional genes, for a total of 14 826 bp, in 21 of those pyraloids plus all 24 outgroups. Maximum likelihood analyses yield trees that, within Pyraloidea, differ little among datasets and character treatments and are strongly supported at all levels of divergence (83% of nodes with bootstrap ≥80%). Subfamily relationships within Pyralidae, all very strongly supported (>90% bootstrap), differ only slightly from a previous morphological analysis, and can be summarized as Galleriinae + Chrysauginae (Phycitinae (Pyralinae + Epipaschiinae)). The main remaining uncertainty involves Chrysauginae, of which the poorly studied Australian genera may constitute the basal elements of Galleriinae + Chrysauginae or even of Pyralidae. In Crambidae the molecular phylogeny is also strongly supported, but conflicts with most previous hypotheses. Among the newly proposed groupings are a ‘wet‐habitat clade’ comprising Acentropinae + Schoenobiinae + Midilinae, and a provisional ‘mustard oil clade’ containing Glaphyriinae, Evergestinae and Noordinae, in which the majority of described larvae feed on Brassicales. Within this clade a previous synonymy of Dichogaminae with the Glaphyriinae is supported. Evergestinae syn. n. and Noordinae syn. n. are here newly synonymized with Glaphyriinae, which appear to be paraphyletic with respect to both. Pyraustinae and Spilomelinae as sampled here are each monophyletic but form a sister group pair. Wurthiinae n. syn. , comprising the single genus Niphopyralis Hampson, which lives in ant nests, are closely related to, apparently subordinate within, and here newly synonymized with, Spilomelinae syn. n.  相似文献   
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