K lalokoploutvým rybám lze vysledovat původ nejstarších čtvernožců (tetrapodů). Přestože dnes přežívají jen dva druhy rodu latimerie (Latimeria), v minulosti tyto ryby představovaly poměrně úspěšnou skupinu vodních obratlovců. Článek popisuje hlavní znaky jednotlivých skupin a jejich minulost., Fossil lobe-finned fishes can be traced as direct ancestors of the first terrestrial tetrapods. Although two species of one genus (coelacanths Latimeria chalumnae and L. menadoensis) have survived to these days, the lobe-finned fishes formed a successful group of aquatic vertebrates in the past. The main features and history of their subgroups are described., and Tomáš Přikryl.
Adult flies of the genus Stomoxys Geoffroy, 1762 (Diptera: Muscidae), especially S. pullus Austen, 1909, S. uruma Shinonaga et Kano, 1966 and S. indicus Picard, 1908, are morphologically similar and sometimes difficult to distinguish when using external morphological characteristics. These species may act as vectors and/or potential vectors of many pathogens (virus, bacteria and protozoa). Their correct identification is important to target the vectors involved in the transmission of the pathogens and also helps in the fly control program.The aim of the present study was to distinguish three species which are difficult to separate using traditional diagnostic characters for species of Stomoxys such as colour patterns and body proportions. Modern morphometrics, both landmark and outline-based, was used to access wing geometry of S. pullus, S. uruma and S. indicus. A total of 198 and 190 wing pictures were analysed for landmark- and outline-based approaches, respectively. Wing shape was able to separate species and sexes of the three Stomoxys flies with highly significant difference of Mahalanobis distances. The cross-validated classification scores ranged from 76% to 100% for landmark and 77% to 96% for outline-based morphometrics. The geometry of wing features appears to be a very useful, low-cost tool to distinguish among the vectors S. pullus, S. uruma and S. indicus. and Tanasak Changbunjong, Suchada Sumruayphol, Thekhawet Weluwanarak, Jiraporn Ruangsittichai, Jean-Pierre Dujardin.
In large parts of Europe Pardosa spp. (Lycosidae) are among the most abundant wolf spiders in arable fields and potentially important natural control agents of pests. We studied the influence of landscape factors on activity density, adult body size and fecundity of P. agrestis in 29 winter oilseed rape fields (Brassica napus L.) in Eastern Austria using pitfall traps. Landscape data were obtained for eight circular landscape sections around each field (radii 250-2000 m). Multivariate regression models were used to analyze the data. Activity density was highest when the length of strips of grassy road-sides in the surroundings was highest and distance to the next grassy fallow lowest. Body size was negatively related to activity density and to the length of road-side strips and positively to woody areas in the vicinity of the fields. Clutch size was unrelated to any of the landscape factors tested but was positively correlated with female body size. Woody areas and grassy fallow in the close vicinity of the fields had a positive influence on number of offspring per female and total number of offspring. These results indicate that various non-crop components in the landscape surrounding oilseed rape fields can specifically influence the activity density and fitness-related traits of P. agrestis in crops. The possible role of Pardosa spp. in natural pest control is discussed. and Thomas Drapela, Thomas Frank, Xaver Heer, Dietmar Moser, Johann G. Zaller.
In this study, the effects of lanthanum were investigated on contents of pigments, chlorophyll (Chl) fluorescence, antioxidative enzymes, and biomass of maize seedlings under salt stress. The results showed that salt stress significantly decreased the contents of Chl and carotenoids, maximum photochemical efficiency of PSII (Fv/Fm), photochemical quenching (qP), and quantum efficiency of PSII photochemistry (ΦPSII), net photosynthetic rate (P N), and biomass. Salt stress increased nonphotochemical quenching (qN), the activities of ascorbate peroxidase, catalase, superoxide dismutase, glutathione peroxidase, and the contents of malondialdehyde and hydrogen peroxide compared with control. Pretreatment with lanthanum prior to salt stress significantly enhanced the contents of Chl and carotenoids, Fv/Fm, qP, qN, ΦPSII, P N, biomass, and activities of the above antioxidant enzymes compared with the salt-stressed plants. Pretreatment with lanthanum also significantly reduced the contents of malondialdehyde and hydrogen peroxide induced by salt stress. Our results suggested that lanthanum can improve salt tolerance of maize seedlings by enhancing the function of photosynthetic apparatus and antioxidant capacity., R. Q. Liu, X. J. Xu, S. Wang, C. J. Shan., and Obsahuje seznam literatury
The theory of life history evolution generally predicts a negative across-environment correlation between development time and size at maturity in response to variations in environmental quality. Deviations from this pattern occur under specific circumstances. In particular, organisms may mature both early and at a small size when (1) some ultimate change (e.g. time constraint, resource exhaustion) in the environment precludes further growth, or (2) when there are predictable among-environment differences in mortality rates. The first scenario is frequently documented in insects but evidence for the second possibility is scarce. Here we report a crowding-induced plastic response resulting in a clear positive across-environment correlation between final weight and development time in a geometrid moth. The response was apparent during the entire larval period and in the last larval instar. Crowding also led to increased growth rates. As outbreaks have not been reported for this species it is unlikely that early pupation is a response to anticipated food shortage. Instead, we suggest that crowded larvae may perceive a higher risk of predation, perhaps because they are unable to distinguish conspecifics from potential predators. A possibility for a plastic increase in growth rate implies that the uncrowded larvae grow at submaximal rates, which indicates a cost of high growth rate., Helen Vellau, Toomas Tammaru., and Obsahuje seznam literatury
Third instar larvae of the genus Acroceratitis Hendel from North Thailand are described for the first time. They belong to A. ceratitina (Bezzi), A. distincta (Zia), A. histrionica (de Meijere), A. incompleta Hardy, and A. septemmaculata Hardy. Short descriptions of eggs, empty egg shells, and puparia are also presented. Acroceratitis larvae infest shoots of bamboo (Poaceae). Larval host plants of the studied species are Bambusa polymorpha Munro, Cephalostachyum pergracile Munro, Dendrocalamus hamiltoni Nees and Arnott ex Munro, D. strictus (Roxbourgh), Dendrocalamus sp. (unidentified) and Pseudoxytenanthera albociliata (Munro). The morphological characters of Acroceratitis larvae are compared with those of other Gastrozonini described so far. A key to Acroceratitis larvae is provided. Acroceratitis ceratitina, A. incompleta and A. septemmaculata are morphologically similar and clearly differentiated from A. distincta and A. histrionica by the lack of additional papillar sensilla on the labial lobe, the arrangement of the spinules on the creeping welts and other characters. The morphological differences between the two groups coincide with the type of substrate utilized by their larvae: A. ceratitina, A. incompleta and A. septemmaculata larvae feed in young and soft internode walls, while A. distincta and A. histrionica utilize harder bamboo tissue of already elongated bamboo shoot internodes. Acroceratitis histrionica larvae are special within the Gastrozonini, because they develop exclusively in cavities formed by the internode surface and the protecting culm sheath. Factors influencing spatial utilization of larval resources, preference for upright shoots as breeding substrate, larval behavior, types of bamboo damage caused by different species and attraction to sweat and urine in the adults are discussed., Alexander Schneider, Damir Kovac, Gary J. Steck, Amnon Freidberg., and Obsahuje bibliografii
Morphology of mature larvae of two Central European species of Scydmaenus Latreille is described and illustrated: S. (s. str.) tarsatus Müller & Kunze and S. (Cholerus) hellwigii (Herbst). Inaccuracies in previous descriptions of S. tarsatus are discussed and the following combination of characters is defined as diagnostic for Scydmaenus: epicranial sutures reaching posteromedian margins of antennal insertions; presence of a single pair of stemmata and epicranial supraantennal pits; anterior row of subtriangular teeth on epipharynx; mandibles falciform and without mesal teeth; antennomere 3 rudimentary; antennal sensory appendage subconical and asymmetrical; maxilla with galea and lacinia; labium strongly constricted between mentum and prementum; thoracic tergites undivided along midline; head capsule, thoracic tergites, laterotergites and abdominal segments except sternite 1 densely setose; thoracic sternites and abdominal sternite1 largely asetose; and lack of urogomphi. We also describe the feeding behaviour of immature S. tarsatus and demonstrate for the first time that Scydmaeninae larvae can feed on live springtails and not armoured mites. In the introduction we provide a summary of the literature on all hitherto known preimaginal stages of Scydmaeninae., Pawel Jaloszynski, Aleksandra Kilian., and Obsahuje seznam literatury