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214. Occurrence of arrhenotoky and thelytoky in a parasitic wasp Venturia canescens (Hymenoptera: Ichneumonidae): effect of endosymbionts or existence of two distinct reproductive modes?

Creator:
Foray, Vincent, Henri, Helene, Martinez, Sonia, Gibert, Patricia, and Desouhant, Emmanuel
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, zoologie, entomologie, Hymenoptera, Ichneumonidae, Venturia canescens, reproductive parasite, thelytokous parthenogenesis, sex evolution, 2, and 59
Language:
English
Description:
Endosymbiotic organisms are known to manipulate the reproductive biology of their hosts. Incomplete prevalence of endosymbiont inducing thelytokous parthenogenesis results in the coexistence of sexual and asexual individuals, and could account for the maintenance of sexual reproduction in certain populations or species. In the parasitoid Venturia canescens, arrhenotokous ("sexual") and thelytokous ("asexual") individuals occur sympatrically. We aimed to determine whether endosymbionts are implicated in the thelytoky of V. canescens. After screening females of the two reproductive modes for several reproductive parasites: bacteria (Wolbachia, Rickettsia, Bacteroidetes, Spiroplasma, Arsenophonus) and Microsporidia, we concluded that thelytoky in V. canescens is not induced by any of these parasites and confirmed its suitability as a biological model for solving the evolutionary enigma of the maintenance of sexual reproduction., Vincent Foray ... [et al.]., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

215. Occurrence of Harmonia axyridis (Coleoptera: Coccinellidae) in field crops

Creator:
Vandereycken, Axel, Brostaux, Yves, Joie, Emilie, Haubruge, Eric, and Verheggen, Francois J.
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, zoologie, entomologie, Coleoptera, Coccinellidae, Harmonia axyridis, habitat, crops, agroecosystems, ladybird, exotic species, 2, and 59
Language:
English
Description:
The Multicoloured Asian Ladybird, Harmonia axyridis Pallas (Coleoptera: Coccinellidae) is known to thrive principally in shrubby and arboreal habitats. This study focuses on the occurrence of this exotic species and its seasonal abundance in various field crops. The abundance of adults, larvae and pupae of H. axyridis was evaluated over a three-year period, from 2009 to 2011, in four important agronomical crops (wheat, corn, broad bean and potato) in Belgium. From May to September, 48 1-m² quadrats were visually inspected in each of the fields sampled on several farms every seven days. H. axyridis colonized and reproduced in all of the four crops studied, with the largest numbers recorded in corn and broad bean crops. Larvae and adults of H. axyridis were recorded mainly in corn and to a much less extent in wheat and potato crops. From 2009 to 2011, the mean weekly abundance of H. ayxridis remained constant except in corn crops, where the recorded densities of all the immature stages and adults were higher in 2011 than in 2009. The population dynamics of aphids and H. axyridis are well described by a symmetric logistic function (S-shape) of cumulative population size. H. axyridis was not always recorded where aphids were abundant, e.g. aphids were abundant on wheat where no H. axyridis were recorded. H. axyridis start reproducing after the peak in aphid population, suggesting that H. axyridis is able to complete its development by feeding on alternative prey such as larvae and pupae of the same and other species of ladybird and other aphidophagous species. H. axyridis is often considered to be bivoltine but it only completes one generation per year in field crops. The second generation generally develops late in the season in other habitats., Axel Vandereycken ... [et al.]., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

217. One variable species or multiple cryptic? Mitochondrial phylogeny of Central and North American Chlosyne lacinia (Lepidoptera: Nymphalidae)

Creator:
Bonebrake, Timothy C., Ward B. Watt, Perez, Alejandro, and Carol L. Boggs
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, entomologie, Salvador, El Salvador, Phylogeny, genetics, tropical, cryptic species, Melitaeini, Chlosyne, 2, and 59
Language:
English
Description:
Recent efforts to catalogue global biodiversity using genetic techniques have uncovered a number of "cryptic" species within morphologically similar populations that had previously been identified as single species. Chlosyne lacinia (Lepidoptera: Nymphalidae), with a range extending from the Southwest U.S. to South America, is one of the most phenotypically variable and broadly distributed butterfly species in the New World. We sampled populations of C. lacinia in two temperate locations (California and Arizona) and one tropical location (El Salvador) to determine if cryptic species were present at this scale (temperate vs. tropical). We examined mtDNA sequence variation in COI, COII, the intervening tRNA (Leucine-2), 16S, 12S and an additional intervening tRNA (Valine), accounting for approximately 20% of the mitochondrial genome (3479 bp). Among all C. lacinia individuals, sequence divergence did not exceed 0.0084 compared to a 0.06 estimated divergence between C. lacinia and congener C. leanira. We also found subclade structure which did not clearly correspond to geography or subspecific designation. Though the mitochondrial phylogeny suggests a complex evolutionary history and biogeography, we demonstrate that one C. lacinia species is distributed throughout North and Central America spanning a diverse set of temperate and tropical habitats. and Timothy C. Bonebrake, Ward B. Watt, Alejandro Perez, Carol L. Boggs.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

218. Orientální bráněnky jako modelová skupina dipterologického výzkumu

Creator:
Rudolf Rozkošný
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, entomologie, dvoukřídlí, entomology, Diptera, 2, and 59
Language:
Czech
Description:
Rozsáhlý materiál bráněnek (Stratiomyidae, Diptera) byl studován z různých částí orientální oblasti včetně chráněných území (národních parků a rezervací). V letech 1994–2012 bylo popsáno více než 60 nových druhů a mnoho dalších druhů revidováno na základě typových jedinců uložených v různých světových sbírkách. Probíhal také sběr larev bráněnek a jejich odchov v laboratorních podmínkách. Jejich ústní ústrojí a povrchové struktury byly studovány s ohledem na jejich potravní specializaci., Extensive material of soldier flies (Stratiomyidae) was examined from different parts of the Oriental region including protected areas (Nature Parks and Reserves). During the 1994–2013 period more than 60 oriental species were described and many further species were revised on the basis of type specimens deposited in various world collections. In addition to the study of adults, mainly phytosaprophagous larvae were collected and reared under laboratory conditions. Their mouthparts and surface structures were examined with regard to their food preference., and Rudolf Rozkošný.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

219. Ovaries of Puto superbus and Ceroputo pilosellae (Hemiptera: Coccoidea): morphology, ultrastructure, phylogenetic and taxonomic implications

Creator:
Michalik, Anna, Kalandyk-Kolodziejczyk, Malgorzata, Simon, Ewa, Kobialka, Michal, and Szklarzewicz, Teresa
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, zoologie, entomologie, Hemiptera, Coccoidea, Puto superbus, Ceroputo pilosellae, ovariole, germ cells, trophocyte, oocyte, scale insects, 2, and 59
Language:
English
Description:
Ovaries of Puto superbus and Ceroputo pilosellae are composed of numerous short telotrophic ovarioles that are arranged around the distal part of the lateral oviduct. An individual ovariole consists of a distal trophic chamber (= tropharium) and proximal vitellarium. The tropharia enclose individual trophocytes (= nurse cells) and early previtellogenic oocytes termed arrested oocytes. A single oocyte develops in each vitellarium. Analysis of serial sections has shown that ovarioles of P. superbus contain from 16 to 51 germ cells (13–43 trophocytes, 2–7 arrested oocytes, 1 developing oocyte) while those of C. pilosellae from only 8 to 10 germ cells (5–7 trophocytes, 0–2 arrested oocytes, 1 developing oocyte). The classification and phylogeny of scale insects are discussed taking into consideration the results of this study., Anna Michalik ... [et al.]., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

220. Parasitism and migration in southern Palaearctic populations of the painted lady butterfly, Vanessa cardui (Lepidoptera: Nymphalidae)

Creator:
Stefanescu, Constanti, R. R. (Richard Robinson) Askew, Corbera, Jordi, and Shaw, Mark R.
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, zoologie, entomologie, Lepidoptera, Nymphalidae, population dynamics, seasonal migration, enemy-free space, primary parasitoids, Cotesia vanessae, secondary parasitoids, 2, and 59
Language:
English
Description:
he painted lady butterfly (Vanessa cardui) (Lepidoptera: Nymphalidae: Nymphalinae) is well known for its seasonal long-distance migrations and for its dramatic population fluctuations between years. Although parasitism has occasionally been noted as an important mortality factor for this butterfly, no comprehensive study has quantified and compared its parasitoid complexes in different geographical areas or seasons. In 2009, a year when this butterfly was extraordinarily abundant in the western Palaearctic, we assessed the spatial and temporal variation in larval parasitism in central Morocco (late winter and autumn) and north-east Spain (spring and late summer). The primary parasitoids in the complexes comprised a few relatively specialized koinobionts that are a regular and important mortality factor in the host populations. However, there was a strong seasonal variation in the level of parasitism. In Spain percentage parasitism was more than four times higher in late summer than in spring (77.3% vs. 18%), while in Morocco it was five times higher by the end of winter than in the autumn (66.2% vs. 13.2%). In both regions the build up of parasitoid populations occurred after V. cardui had bred in the same general area over successive generations, and this may represent a selective force favouring seasonal migration to enemy-free space., Constanti Stefanescu ... [et al.]., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

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