Patogeny lýkožroutů (kůrovců) zahrnují široké spektrum druhů z různých skupin od prvoků, mikrosporidií a hub až po zelené řasy. Napadené jedince lze poznat až na základě pitvy a analýzy pod mikroskopem, nevykazují žádné vnější projevy onemocnění. U většiny druhů patogenů navíc neznáme konkrétní vlivy na napadené jedince, snad s výjimkou nemocí rozkládajících tukové těleso, kdy dochází k úhynu hostitele během přezimování nebo v požerku. Často se uvádí možný význam patogenů pro využití v biologickém boji proti kůrovcům, praktická aplikace je však stále problematická vzhledem ke kryptickému způsobu života brouků pod kůrou a obtížné (i nákladné) kultivaci., Pathogens of bark beetles (Scolytinae) include a broad spectrum of species from different groups of protozoa, microsporidia and fungi to green algae. Individuals with infection can only be recognized after dissection and microscopic analysis; they show no external signs of disease. In addition, we don't know the effects of most pathogen species on the infested individuals, perhaps with the exception of diseased decomposing fat body, which leads to the death of the host during hibernation or in the breeding system. Potential use of pathogens in biological control against bark beetles is often discussed in the literature, but practical application is still problematic due to the cryptic nature of beetles' life under the bark and difficult (and expensive) cultivation of pathogens., and Karolina Lukášová, Jaroslav Holuša.
Někteří zástupci třídy hmyzu patří k chladově nejodolnějším organismům na Zemi. Přežijí podchlazení až pod -50°C nebo kompletní zmrznutí (přeměnu tělní vody na led). Dokonce je dokážeme, jako celé komplexní organismy, téměř neomezeně dlouho skladovat v kapalném dusíku. Výzkum principiální podstaty této výjimečné schopnosti hmyzu může přinést poznatky využitelné pro praktické technologie kryokonzervace biologického materiálu., Some insects are to the most cold-tolerant organisms on Earth. They survive supercooling down to -50°C or complete freezing (transition of body water to ice). Moreover, we can store the insect organism in its whole complexity in liquid nitrogen almost indefinitely. Research on the principles behind this exceptional ability of insects can provide knowledge that will be useful for the development of practical protocols for the cryopreservation of biological material., and Vladimír Košťál.
A revision of species of the genus Macroscytus Fieber distributed in Madagascar and adjacent islands is presented. Four previously known species [M. fryeri Distant, M. lobatus Signoret, M. madagascariensis (Signoret), M. privignus Horváth] are redescribed, and lectotypes are designated for three of them. Four new species (M. mayottensis sp. n., M. simulans sp. n., M. tamatavei sp. n., and M. viettei sp. n.) are described and compared with their congeners. A key to all species of the genus known from Madagascar and adjacent islands is also provided., Jerzy A. Lis, and Lit
Myrmica rubra is a northern, temperate Palaearctic ant species with a geographical range that extends from the Atlantic coast of Europe to central Asia. In Europe, its range covers > 25° of latitude where it lives under a variety of climates that vary from extreme oceanic in the west, to continental in the east. Colonies nest in the soil and their life cycles are known to be highly dependent on ambient temperature and soil moisture. We hypothesised that the brood-rearing behaviour of populations might be focally adapted to climate and that we might detect differences when the ants were reared under \"common-garden\" conditions. Brood-rearing behaviour was compared for 38 colonies of M. rubra drawn from 13 populations representing a range of 6 latitudes: all 6 were represented in eastern Europe and 2 in western Europe. A sample of ants from each colony was used to estimate respiration rate, body mass and fat content at the start of the experiment in spring (immediately post hibernation) and at the end of the experiment (mid summer). Respiration had a linear relationship with latitude, with northern populations having greater respiration rate in spring compared to southern populations. It is suggested that this is an adaptation to different seasonality over the species' range that results in the \"more active\" northern workers rearing fewer brood to maturity more quickly than southern workers. Fat content, a measure of worker \"quality\", had a parabolic relationship with latitude with mid latitude colonies having the fattest workers. Fatter workers appeared to rear heavier brood. This probably represented a functional response to environment with populations living at \"edge of range\" sites being physiologically more stressed and performing brood-rearing tasks less well than centre of range populations. We believe that this is the first demonstration of a consistent, intra-specific trend for Variation in the social physiology of an ant species over its geographic range., Graham W. Elmes, Judith C. Wardlaw, Mogens G. Nielsen, Vladilen E. Kipyatko, Elena B. Lopatina, Alexander G. Radchenko, Boyd Barr, and Lit
Pro rok 2013 se stal evropským pavoukem roku sklípkánek hnědý (Atypus affinis). Jde o jednoho ze tří druhů sklípkanů vyskytujících se v České republice. V článku popisuji morfologii, způsob života, stanovištní nároky a rozšíření sklípkánka hnědého. Je naším nejhojnějším zástupcem rodu, vyskytuje se na suchých osluněných kamenitých stráních s řídkou stromovou vegetací. Jeho stanoviště nejsou bezprostředně ohrožena sílícím zarůstáním krajiny., The Purse-Web Spider (Atypus affinis) became the European Spider of the Year 2013. The genus Atypus comprises three species in Europe. The morphology, natural history, habitat requirements and distribution of A. affinis are described. In Central Europe, it is the most common Atypus species and it occurs on dry sunny rocky slopes with sparse woody vegetation. These habitats do not tend to be overgrown by expansive tree or grass species., and Milan Řezáč.
There is much current discussion about the factors that control the distribution and abundance of animal species, particularly at the edges of their range. The significance of temperature for survival and development is compared in two closely related psyllid species (Craspedolepta nebulosa and C. subpunctata) living on the same host plant (Chamerion angustifolium) (Onagraceae) but displaying different distributions along latitudinal and altitudinal gradients. The following measurements were made at critical periods during the life cycle (a) winter supercooling points (SCPs), (b) tolerance of short (1 min) and long term (1-25) days exposure to sub-zero temperatures above the SCP, (c) tolerance of short term exposure to high spring/summer temperatures and (d) comparative field development rates among species and sites during the early critical part of the growing season. Successful completion of the life cycle is related to heat availability during the growing season. This appears to limit the distribution of the Craspedolepta species, rather than their survival response to thermal extremes. No significant differences were found between the two species in the supercooling point or in their long and short term survival responses at low or high temperatures., Jeremy M. Bird, Ian D. Hodkinson, and Lit
The effects of 5 pmols of adipokinetic hormone (Lom-AKH-I) on both the locomotion and mobilization of lipids were studied in 10-day-old diapausing adult females of the short-winged (brachypterous) morph of Pyrrhocoris apterus (L.). The results revealed that AKH stimulation of locomotion in this bug is wing-morph independent. The stimulatory effect of AKH on locomotion was shown to be positively correlated with its effect on lipid mobilization., Radomír Socha, Dalibor Kodrík, Rostislav Zemek, and Lit
Článek vychází z pozorování výskytu kobylky malé (Phaneroptera nana) v centru Prahy. Představuje blíže tento druh, jeho rozšíření, prazskou mikropopulaci a poznatky z chovu v insektáriu., This article is based on observations of the Mediterranean Katydid (Phaneroptera nana) in the centre of Prague. It presents the species, its spread, its Prague micropopulation and information on insectarium breeding in some detail., and Pavel Pecina.
Střevlík uherský (Carabus hugaricus hungaricus) je druhem dlouhostébelných panonských stepí. Patří mezi zvláště chráněné brouky a je rovněž druhem evropsky významným. V České republice přežívá už pouze na Pouzdřanské stepi a na Pálavě. V článku shrnujeme výsledky výzkumů jeho stanovištních preferencí, demografie a mobility, diskutujeme možnosti jeho ochrany a zároveň se dotýkáme bolestivého tématu ochranářské péče o lokality tohoto druhu., The Carabus hungaricus ground beetle is a highly endangered, dry-grassland specialist listed in the EU Habitats Directive. In the Czech Republic, the beetle survives on the last two sites including the Pouzdřany steppe, and the Pálava hills. Here we report results of extensive mark-recapture studies of this species, including its habitat preference, demography, and dispersal abilities. Furthermore, we discuss the options for its conservation and conservation management of the two inhabited sites., Lukáš Čížek ... [et al.]., and Pokračování čl. na str. CXV kuléru Živy 5/2014
The presence of adipokinetic activity in crude extracts of corpora cardiaca (CC) from the butterfly (Vanessa cardui L., Nymphalidae) was demonstrated by bioassay and Mas-AKH was revealed as the major adipokinetic hormone (AKH) by use of two different technologies of sequence elucidation: HPLC separation of the peptide followed by Edman degradation and Q-TOF mass spectrometry. In contrast to the time- and material-consuming conventional methods of peptide purification and sequencing, substantial structural data of the peptide were confirmed - post factum - from one pCC (pair of CC) by Q-TOF mass spectrometry. Only males of our laboratory colony showed a significant lipid increase in the haemolymph after injection of either crude CC extract (1 pCC equivalent) or 10 pmol of synthetic peptide., Gabriele Köllisch, Peter D. Verhaert, Matthias W. Lorenz, Roland Kellner, Gerd Gäde, Klaus H. Hoffmann, and Lit