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1.
Female imagines, subimagines, eggs and larvae of Electrogena antalyensis (Kazanci & Braasch) from Turkey are described for the first time. The results of a thorough analysis of larvae, based on the standard set of diagnostic characters for the identification of Electrogena species, are reported. The peculiarity of several characters places E. antalyensis in an isolated position within the genus Electrogena.  相似文献   

2.
The thermally induced helix-coil transitions of three A-T DNAs, d(A)n·d(T)n, d(A-T)n·d(A-T)n, and d(A-A-T)n·d(A-T-T)n, were studied. Experimental transition curves of the DNAs were analyzed using the loop entropy model of DNA melting. The calculation of the melting curve of d(A-A-T)n·d(A-T-T)n is presented using the integral equation formalism of Goel and Montroll. The aim of this work was to evaluate thermodynamic parameters which govern DNA stability and to test the theoretical model employed in the analysis. Our results show (1) an excellent over-all agreement between theory and experiment, (2) a loop entropy exponent k = 1.55 ± 0.05 provided the best fit to all the polymer transition curves, (3) the evaluated stacking free energies reflect the relative stability of the DNAs, and (4) the stacking energies of the ApA·TpT dimer evaluated from d(A)n·d(T)n and d(A-A-T)n·d(A-T-T)n differ. The last result is consistent with different conformations for the dimer in these two polymers.  相似文献   

3.
Protozoan epibionts were found on specimens of the mysid Mysis relicta collected in Lake Lü?iai (Lithuania). These protozoans belong to three genera of ciliates: Vorticella, Dendrosoma and Tokophrya, and were located on the antennae, carapace, appendages and abdomen of the basibiont. The ciliates of the genus Vorticella had a bell‐shaped body, with concave‐type striations and a very long contractile stalk. The stalk joined the body via a truncated and overlapping zone. The macronucleus was J‐shaped, and the contractile vacuole was anterolateral. Only one ciliate species of Vorticella has been found on mysids, although on species other than M. relicta, and this is therefore the first record of Vorticella on M. relicta, and the second on the order Mysidacea. The ciliates of the genus Dendrosoma had an irregular body directly attached to the substrate. Finger‐like actinophores arose from the body, with a bundle of tentacles at their ends. The macronucleus ramified into branches that followed the actinophores. These ciliates were included in the species D. astaci. The presence of this ciliate represents the first record of this genus on Mysis relicta. The ciliates of the genus Tokophrya had a pyramidal body, the apical surface of which showed two conspicuous actinophores, with a short, longitudinally striated stalk joining to the body via a narrow unstriated band. The macronucleus was spherical or ovoid, centrally located, and there was an apical contractile vacuole. Only one previous study has referred to the presence of this genus on Mysis relicta, and the data contained in it were compared with those of the present study. The biometrical data and taxonomical position of the ciliate epibionts was considered.  相似文献   

4.
A new subspecies, Kailasius autocrator murun Korb, ssp. n., of the species Kailasius autocrator (Avinov, 1913) from the eastern part of the Alai Mountain Ridge is described. This subspecies differs from the other known ones in the smaller size (the fore-wing length is less than 23 mm) and in the presence of 5 black rounded spots in the submarginal area of the hind-wing upper side (4 spots in the nominotypical subspecies and K. a. pshartanus). The new subspecies is shown to be the most archaic one among the subspecies of the genus Kailasius by the wing pattern. Possible ways for the origin of local and small populations of morphologically different subspecies of the genus are discussed.  相似文献   

5.
Siderocelis irregularis Hindák, representing a genus Siderocelis (Naumann) Fott that is known from European temperate waters, was identified as a common phytoplankter in Lake Tanganyika. It was found aposymbiotic as well as ingested (possibly endosymbiotic) in lake heterotrophs, mainly Strombidium sp. and Vorticella spp. The morphology and ultrastructure of the species, studied with LM, SEM and TEM, are described with emphasis on the structure of the cell wall and the pyrenoid. Presented at the International Symposium Biology and Taxonomy of Green Algae V, Smolenice, June 26–29, 2007, Slovakia.  相似文献   

6.
Summary The life cycle and social behaviour of the sweat bee Lasioglossum (Evylaeus) baleicum (Cockerell) was investigated in two geographically separate populations in Hokkaido, northern Japan. Colonies were excavated throughout the brood rearing season from an aggregation in Nishioka forest park, Sapporo, and near Kawakita in eastern Hokkaido during 2000 and 2001. The Nishioka population produced two discrete broods during the year and was weakly eusocial; 57% of workers were mated and 28% exhibited some ovarian development, 12–16% of the first brood was male, and workers were on average 4.5% smaller than their respective queen. In contrast, the population at Kawakita was solitary, and produced a single brood per year with an unbiased sex ratio. In addition however, there were some solitary colonies in the Nishioka population and evidence of a partial second brood in some colonies at Kawakita, suggesting differences between the populations are not fixed and that this species is truly socially polymorphic. L. (E.) baleicum is a member of the fulvicorne species group, which includes other examples of social polymorphic species as well as solitary and eusocial species, though this is the only species of this group so far known to exhibit a solitary/non-delayed eusocial polymorphism. Recent studies suggest that social polymorphism has both genetic and environmental influences, raising questions as to the relative import of each.  相似文献   

7.
8.
This study reports on infection by Trypanoxyuris (Trypanoxyuris) minutus among Alouatta guariba clamitans through biometry on adults and eggs. A total of 58 adult helminths were recovered from the small segment of the animal's large intestine. This study is the first report of this parasite among A. guariba clamitans in Rio de Janeiro.  相似文献   

9.
1. Bythotrephes cederstroemi (Crustacea: Onychopoda: Cercopagidae) invaded Harp Lake, Ontario in 1993, since when the zooplankton community has shifted from dominance of small-bodied to large-bodied species. During 1995 diets of adult lake herring (Coregonus artedii), Harp Lake’s primary planktivorous fish, were examined to determine the extent to which this conspicuous zooplankter has become integrated into the lake’s foodweb and whether fish condition has been affected in consequence. 2. Bythotrephes and Daphnia galeata mendotae were strongly preferred prey, whilst Holopedium gibberum and calanoid and cyclopoid copepods were negatively selected by lake herring. Predation on Bythotrephes and Holopedium was not size-selective, although D. galeata mendotae and calanoid copepods (Leptodiaptomus minutus and L. sicilis) consumed by herring were significantly larger than co-occurring conspecifics in the lake. 3. Caudal spines of Bythotrephes may form boluses in lake herring stomachs. However, the number of caudal spines in fish digestive tracts did not differ significantly from the number of Bythotrephes’ mandible pairs, indicating that the former were not differentially retained. 4. Lake herring weight-at-length relationships in lakes in Muskoka, Ontario, invaded by Bythotrephes did not differ from those in adjacent non-invaded lakes, indicating that Bythotrephes invasion of lakes apparently has not affected condition of lake herring.  相似文献   

10.
Abstract: ‘Totanuslartetianus, Elorius paludicola and ‘Tringagracilis are the three scolopacid birds from the early Miocene of Saint‐Gérand‐le‐Puy described by the French palaeontologist Milne‐Edwards in the 19th century. Since then, no revision of these taxa has been performed. Our re‐examination revealed that not much of the material originally assigned to ‘Totanuslartetianus can be retained within the species. Presumably plesiomorphic features of the humerus – and potentially the coracoid we attributed to this taxon – indicate that it is misplaced in the extant scolopacid genus and may not even belong to the Scolopacidae (sandpipers and allies), and we therefore place it in the new genus Scolopacimilis. Comparisons of the material assigned to Elorius paludicola and ‘Tringagracilis show that they are morphologically similar, both exhibiting distinct scolopacid anatomical features. The latter, however, cannot be referred to the extant taxon Tringa and is classified into the new genus Parvelorius. We further introduce three new species, ?Elorius limosoides sp. nov., and ?Parvelorius calidris sp. nov., which we have tentatively assigned to the extinct scolopacid genera Elorius and Parvelorius, respectively, and Becassius charadriioides gen. et. sp. nov., which, together with Scolopacimilis, display a morphology uncharacteristic for extant Scolopaci. For the first time we have assigned skulls to some of the postcranial elements described in this study. The presence of at least six species of Scolopaci from the early Miocene considerably increases the number of members of the group known from this time.  相似文献   

11.
12.
In the Dijon area, the top of the Athleta zone contains rich ammonite fauna dominated quantitatively by two families: Perisphinctidae and Oppeliidae. The Oppeliidae are diversified and make up a numerically larger proportion of the ammonite fauna than in the underlying strata (up to 57 %). The exceptional state of preservation of the ammonites has permitted a precise study to be made of ontogenesis and intraspecific variability. Four sub-families are found (Oppeliinae, Hecticoceratinae, Distichoceratinae and Taramelliceratinae), within which sexual dimorphs have been recognised. One small form, characterized by lappets and a body chamber with ellipticoidal-trending coiling, is interpreted as the microconch dimorph of the Paralcidia genus which was unknown until now. One specimen of Creniceras, the oldest collected in Côte-d'Or, can be interpreted as the microconch dimorph of Taramelliceras.

Résumé

Dans la région dijonnaise, le sommet de la zone à Athleta renferme une riche faune ammonitique, quantitativement dominée par deux familles : Perisphinctidae et Oppeliidae. Par rapport aux niveaux sous-jacents, la famille des Oppeliidae est diversifiée et représente une part numériquement plus importante de la faune ammonitique (jusqu'à 57 %). L'excellente conservation des ammonites a autorisé une étude précise de l'ontogenèse et de la variabilité intraspécifique au sein de la famille. Quatre sous-familles sont représentées (Oppeliinae, Hecticoceratinae, Distichoceratinae et Taramelliceratinae), au sein desquelles les dimorphes sexuels ont été reconnus. Une petite forme, caractérisée par des apophyses jugales et une chambre d'habitation à enroulement à tendance ellipticoïde, est interprétée comme le dimorphe microconque, inconnu jusqu'à présent, du genre Paralcidia. Un spécimen de Creniceras, le plus ancien récolté en Côte-d'Or, pourrait correspondre au dimorphe microconque des Taramelliceras.  相似文献   

13.
The parasitoid complexes of 22 species of the genus Phyllonorycter reared from 20 host plants were studied in the Middle Volga Basin. From a total of 124 host-parasitoid associations analyzed, 88 had been previously unknown. Minotetrastichus frontalis, Sympiesis sericeicornis, Pnigalio soemius, Closterocerus formosus, and S. gordius were the most frequent species. The highest percentage of parasitoids reared was observed in Ph. ulmifoliella (58.6%) and Ph. sylvella (54%), and the lowest one, in Ph. salictella (15%). Ph. corylifoliella (95.7%), Ph. populifoiella (95.5%) and Ph. insignitella (95.5%) had the highest mortality due to parasitoids. The number of endoparasitoid species prevailed over that of ectoparasitoids in the parasitoid complexes of the genus Phyllonorycter, but the number of individuals reared was 4 times greater for ectoparasitoids. The parasitoid complexes were the most similar in Ph. harrisella and Ph. quercifoliella on Quercus robur. The gregarious ectoparasitoid M. frontalis predominated over parasitoids of Phyllonorycter.  相似文献   

14.
Scinax fuscomarginatus, Scinax parkeri, Scinax trilineatus, Scinax lutzorum, and Scinax pusillus are morphologically similar species with controversial taxonomy associated with open formations of South America east of the Andes. We used external morphology, advertisement call, and molecular sequences to assess the taxonomy of these species. Phylogenetic analysis of molecular data showed a well‐supported monophyletic group divided into two main clades and several subclades. Specimens of Hyla madeirae (synonym of S. fuscomarginatus) and those from Serra do Cachimbo correspond to distinct subclades, whereas the currently valid species were grouped into a single clade. This clade showed a marked substructure, but concordance of the recognized species to subclades was limited, showing S. fuscomarginatus to be paraphyletic with respect to S. parkeri, S. trilineatus, S. lutzorum, and S. pusillus. The high intrapopulation and intraspecific variation found in morphological characters did not allow us to differentiate amongst the currently recognized species. Similarly, none of them was distinguishable by morphometric analysis or advertisement call. Based on multiple evidence, we propose the synonymy of S. parkeri, S. trilineatus, S. lutzorum, and S. pusillus with S. fuscomarginatus, the revalidation of H. madeirae, and describe the specimens from Serra do Cachimbo as a new species. © 2014 The Linnean Society of London  相似文献   

15.
Miscanthus and Saccharum are closely related perennial C4 grasses. Miscanthus has recently attracted interest as a non-food crop for energy and fibre production. However, molecular genetic tools for the selection of new Miscanthus genotypes and study of its genetic resources are limited. We have identified six chloroplast (plastid) marker loci,containing both microsatellites (cpSSRs) and single nucleotide polymorphisms (SNPs) and developed primers to amplify and sequence these regions. The primers were designed using the complete chloroplast genome sequence of sugarcane and were tested on a collection of 164 Miscanthus genotypes and 14 related species of the subfamily Panicoideae. The cpSSR markers were highly polymorphic, with the number of alleles ranging from 10 to 16 per locus. Within the six cpSSR marker loci, the hybrid M. ×giganteus exhibits virtually no cpDNA variation compared with its putative parents M. sinensis and M. sacchariflorus. These SNP markers enable the differentiation of most Miscanthus species and detect infraspecific variation suitable for defining cytoplasmic genepools of Miscanthus for breeding purposes.  相似文献   

16.
C–N bond activation of tert-butyl isocyanide in methanol using 2,6-bis(di-tert-butylphosphinito)pyridine (PONOP) metal (Ni, Pd, Pt) complexes and (dippe)NiCl2 are reported. t-BuOMe and t-BuCl were detected as organic products by GC–MS. Substitution of the metal-chloride by one molecule of tert-butyl isocyanide followed by carbonium ion loss/nucleophilic attack by chloride anion or methanol led to formation of a metal-cyanide bond.  相似文献   

17.
Specimens of Askenasia volvox from southwestern Indiana have a variable body shape and a size range of 29 × 22 μ m to 42 × 27 μ m. The pectinelles, membranelles, and cirri each number 47–48, and respectively have a length of 8–10, 20, and 30 μ m. The pectinelles arise from ciliary rows consisting of ~10 kinetosomes, and every membranelle originates from 2 adjacent rows of ~14–17 kinetosomes. Different algae as well as Bodo and certain other protozoa are ingested. The macronucleus, micronucleus, the cytoplasm and its inclusions, trichites, the function of the contractile vacuole, and movements and behavior are described.  相似文献   

18.
Both C?C‐bond isomers of cyclohexadec‐7‐enone ( 6 , Aurelione®) were selectively synthesized via cyclohexadec‐7‐ynol ( 16 ) by ring‐closing alkyne metathesis of icosa‐2,18‐diyn‐9‐ol ( 15 ), employing an in situ‐formed catalyst from Mo(CO)6 and 4‐(trifluoromethyl)phenol. Pyridinium chlorochromate (PCC) oxidation and subsequent Lindlar hydrogenation afforded the (7Z)‐configured isomer (7Z)‐ 6 , while hydrosilylation of the intermediate cyclohexadec‐7‐ynone ( 17 ), followed by desilylation, provided the (7E)‐configured cyclohexadec‐7‐enone ((7E)‐ 6 ). The substrate for the alkyne metathesis was prepared from cycloheptanone ( 7 ) by cycloaddition of chloromethylcarbene to its trimethylsilyl enol ether 8 , and subsequent ring enlargement of the adduct 9 under rearrangement to 2‐methylcyclooct‐2‐enone ( 10 ), which was subjected to Weitz? Scheffer epoxidation and Eschenmoser? Ohloff fragmentation to non‐7‐ynal ( 12 ). Its reaction with the Grignard reagent of 11‐bromoundec‐2‐yne ( 14 ), prepared from the corresponding alcohol 13 by Appel? Lee bromination, furnished the icosa‐2,18‐diyn‐9‐ol ( 15 ). While both isomers of cyclohexadec‐7‐enone ( 6 ) possess warm and powdery musk odors with tobacco‐type ambery accents, (7Z)‐ 6 is more animalic and waxy, whereas (7E)‐ 6 was found to be more floral, sweet, and hay‐like in tonality. Interestingly, however, with odor detection thresholds of 2.0 ng/l air and 2.3 ng/l air, respectively, both (7Z)‐ 6 and (7E)‐ 6 were found to be almost identical in their odor strength, with the (7Z)‐ 6 being only very slightly more powerful.  相似文献   

19.
The anatomy of the muscular system of Barentsia discreta (Kamptozoa) was studied by confocal laser scanning and transmission electron microscopy. The calyx musculature, muscles associated with the digestive tract, atrial ring muscles, and tentacle muscles are described. The structure of the muscular bulbus located in the upper part of the stalk and the muscle base of the stalk were examined. The middle part of the stalk and the stolon lack musculature. The structure of the star-cell complex lying at the boundary of the stalk and calyx was examined in detail. Emschermann’s (1969) opinion was confirmed that the star-cell complex performs the function of a heart, providing the transport of substances from the calyx to the stalk and stolon. The general plan of the muscle arrangement is similar in all Kamptozoa; it consists of central muscles of the calyx, atrial ring muscles, tentacle muscles, and muscles associated with the digestive tract. Oral, lateral, and aboral muscles extending from the stalk into the calyx, which were described for solitary forms, are lacking in the calyx of colonial B. discreta. The calyx of B. discreta is separated from the stalk by a septum, through which muscles do not penetrate from the stalk.  相似文献   

20.
In the period 1993–2006, during investigation of reproduction biology of the bearded tit, 106 deserted nests of the species were collected in Slovakia, Austria and Italy and their arthropod fauna was analyzed. Occasionally introduced individuals of the pseudoscorpion Lamprochernes nodosus, a frequent species in Central Europe, were recorded in the nests. Altogether 984 individuals and 33 species of mesostigmatic mites (Acari) were found in 46.2% of the nests examined. The ectoparasite Ornithonyssus sylviarum was most abundant and frequent; it represented almost 68.3% of all individuals. Due to it, the parasitic mites predominated (69.4% of individuals). Other ecological groups were less represented: edaphic detriticols − 11.6%, coprophils − 10.7%, species of vegetation stratum − 8.2%, and nidicols − 0.2%. Beetles (40 species, 246 individuals) were present in 57 nests. Most of the beetles were strongly hygrophilous species inhabiting soil surface in the reed stands or other types of wetlands and the shore vegetation. Predators represented 59% of all individuals. They might find food in the nests, but none of the species had a close relationship to bird nests and represented 35% of species. All beetle species penetrated the nests occasionally, when ascending on the vegetation or searching cover during periods of increased water level. Occasionally, larvae and nymphs of the Dermacentor marginatus tick were found. They were most probably introduced by insectivores of the genus Neomys. Only one species of fleas, Ceratophyllus garei — a parasite of birds nesting in humid environment, was recorded in the nests.  相似文献   

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