Maternal effects of heat shock are reported for some species of insects, but little is known about such effects in the western flower thrips (WFT) Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae). WFT is a pest of vegetables in greenhouses worldwide. It is susceptible to high temperatures in its natural environment and is controlled using heat treatment in China. WFT population growth is suppressed by a brief exposure to a high temperature of 40°C or 45°C in the laboratory. To explore the mechanism by which high temperatures suppress the growth of WFT populations, as well as the effects of multiple heat treatments on WFT, we recorded the duration of development and survival of immature WFT, and the sex ratio (female/male) and fecundity of F1, F2, F3 and F4 adult females that developed after a single heat shock, and those of F2 offspring after a double heat shock. We also recorded the longevity and ovarian structure of adult females of the treated generation (P) and their F1, F2 and F3 offspring after a single heat shock. In addition, we determined whether the effects of a heat shock on second instar nymphs and adults differed. The results indicate that exposure of the parental generation to 41°C or 45°C for 2 h significantly prolonged the duration of development, reduced survival of immature WFT and altered the sex ratio (female/male), longevity and fertility of their adult female offspring. The effects of a heat shock of 41°C persisted for two generations, whilst the effect of heat shock of 45°C persisted for three generations. In addition, double heat shocks had more pronounced effects than a single heat shock. Heat shock administered to second instar nymphs resulted in a decrease in the number of ovarioles, whilst a heat shock administered to adults resulted in ovariole deformity. The maternal effects of heat shock in terms of the biological parameters of WFT, structure and number of ovarioles, are critical in determining the suppression of the growth at high temperatures of WFT populations.
Melatonin is a well-known bioactive molecule able to mitigate photooxidative damage caused by excess light. Here we have shown that mutant Arabidopsis lines with disrupted genes for melatonin putative receptor CAND2/PMTR1 and GPA1 encoding the α-subunit of heterotrimeric G-protein were partially insensitive to melatonin treatment under high light stress. They exhibited a higher degree of photodamage due to a significantly decreased photosynthetic activity and diminished expression of chloroplast and nuclear-encoded genes and the corresponding proteins. A possible mechanism for melatonin-dependent regulation of chloroplast genes is associated with a change in the activity of the genes for chloroplast RNA polymerases. We conclude that under high light stress, melatonin may act as a hormone-like signaling molecule via the CAND2/PMTR1-mediated signaling pathway.
The Mediterranean flour moth, Ephestia kuehniella is a widespread pest of stored products and a classical object in experimental biology. In the present study, we determined its complete mitochondrial genome sequence. The genome is circular, consists of 15,327 bp and comprises 13 protein-coding, 2 rRNA- and 22 tRNA-coding genes in an order typical for the Ditrysia clade of the order Lepidoptera. A phylogenetic study of the Lepidoptera based on complete mitochondrial genomes places E. kuehniella correctly in the family Pyralidae and supports major lepidopteran taxa as phylogenetic clades. The W chromosome of E. kuehniella is an exceptionally rich reservoir of originally mitochondrial sequences (numts). Around 0.7% of the W DNA was found to be of mitochondrial origin, 83% of the mitogenome sequence was represented between 1-11 × in the W chromosome. Phylogenetic analysis further revealed that these numts are an evolutionary recent acquisition of the W chromosome., Katrin Lämmermann, Heiko Vogel, Walther Traut., and Obsahuje bibliografii
Synechococcus is one of the most abundant photoautotrophic picoplankton in the marine ecosystem. However, it is not clear how Synechococcus assemblages respond to light intensity variation in a genus group. Here, enriched Synechococcus assemblages from in situ coastal seawater were subjected to light intensity simulation experiments in a range of 9-243 μmol(photon) m-2 s-1. Characteristics concerning physiology, genomics, and metatranscriptomics were analyzed. Physiologically, the fitting model predicted photosynthesis indications and pigment contents increased with different trends following the light intensity. Genomic sequencing demonstrated that both the phylogenetic and phenotypic compositions of Synechococcus assemblage exhibited population succession. Especially, the proportion of Synechococcus pigment type 2 was changed significantly. In metatranscriptomics, most genes were downregulated in the high-light intensity group, while photosynthesis-related genes were entirely upregulated. The high upregulation of photosynthesis-related genes, such as psbO, psbA, apcB, and cpcB, corresponded to the succession of Synechococcus genotype and was responsible for the physiological shift in response to light intensity.
Companion animals can be infested by various species of parasitic insects. Cat flea Ctenocephalides felis (C. felis felis) (Bouché, 1835) and dog flea Ctenocephalides canis (Curtis, 1826) belong to multihost external parasites of mammals, which most frequently occur on domestic cats Felis catus Linnaeus and dogs Canis familiaris Linnaeus. The main aim of this study was to investigate the presence of pathogens, such as Anaplasma phagocytophilum (syn. Ehrlichia phagocytophila) and Rickettsia spp., in adult C. felis and C. canis fleas. Flea sampling has been realised from January 2013 to April 2017 in veterinary clinics, animal shelters and pet grooming salons. Fleas were collected from domestic cats and dogs, directly from the pet skin or hair. Then, the DNA was isolated from a single flea by using the alkaline hydrolysis and samples were screened for the presence of pathogens using PCR method. Anaplasma phagocytophilum has occurred in 29% of examined C. felis and 16% of C. canis individuals. In turn, the prevalence of Rickettsia spp. in cat fleas population was only 3%, and the dog fleas 7%. The present study showed the presence of pathogenic agents in cat and dog fleas, which indicates the potential role of these insects in circulation of A. phagocytophilum and Rickettsia spp. in the natural habitat. Furthermore, exposition to these flea species, whose hosts are domestic cats and dogs, can pose a potential risk of infection for humans.
Large and small rDNA sequences of 41 species of the family Opecoelidae are utilised to produce phylogenetic inference trees, using brachycladioids and lepocreadioids as outgroups. Sequences were newly generated for 13 species. The resulting Bayesian trees show a monophyletic Opecoelidae. The earliest divergent group is the Stenakrinae, based on two species which are not of the type-genus. The next well-supported clade to diverge is constituted of three species of Helicometra Odhner, 1902. Based on this tree and the characters of the egg and uterus, a new subfamily, the Helicometrinae, is erected and defined to include the genera Helicometra, Helicometrina Linton, 1910 and Neohelicometra Siddiqi et Cable, 1960. The subfamily Opecoelinae is found to be monophyletic, but the Plagioporinae is paraphyletic. The single representative of the Opecoelininae (not of the type genus) is nested within a group of deep-sea 'plagioporines'. The two representatives of the Opistholebetidae are embedded within a group of shallow-water 'plagioporine' species. The Opistholebetidae is reduced to subfamily status pro tem as its morphological and biological characteristics are distinctive. This implies that as opecoelid systematics develops with more molecular evidence, several further subfamilies will be recognised. Many of the morphological characters were found to be homoplasious, but the characters defining the Helicometrinae and Opecoelinae, such as filamented eggs, reduced cirrus-sac and uterine seminal receptacle, are closely correlated with the inferred phylogeny., Rodney A. Bray, Thomas H. Cribb, D. Timothy J. Littlewood, Andrea Waeschenbach., and Obsahuje bibliografii
Specimens of Neoechinorhynchus (Neoechinorhynchus) poonchensis sp. n. are described from Schizothorax richardsonii (Gray) in the Poonch River, Jammu and Kashmir. Specimens are thick-walled with dissimilar dorsal and ventral para-receptacle structures, anteriorly manubriated hooks, two giant nuclei in each lemniscus and many subcutaneousy. The lemnisci barely overlap the larger anterior testis, the cement gland has eight giant nuclei, and the seminal vesicle is large with thin walls. The vagina is unremarkable but the long uterus is made up of four specialised regions. Neoechinorhynchus rigidus (Van Cleave, 1928), resembles N. poonchensis sp. n. It is distinguished from N. poonchensis sp. n. by having smaller trunk, proboscis, and male reproductive structures, equal testes, unequal lemnisci with three giant nuclei each, and much larger anterior proboscis hook (130 μm in males) than that originally described by Van Cleave (1928) (70 μm in a female). Anterior hook length alone is sufficient to conclude that the N. rigidus of Datta (1937) is not the same species as the N. rigidus of Van Cleave (1928). Van Cleave's (1928) species remains valid and that of Datta (1937) is considered a different species named Neoechinorhynchus pseudorigidus sp. n., herein. Micropores of N. poonchensis sp. n. have variable distribution in different trunk regions and the Energy Dispersive X-ray analysis demonstrated higher levels of sulfur and lower levels of calcium and phosphorus. Sequences of the 18S rDNA gene from nuclear DNA, and cytochrome c oxidase subunit I (cox1) from mitochondrial DNA of N. poonchensis sp. n. were amplified and aligned with other sequences available on GenBank. Maximum likelihood (ML) and Bayesian inference (BI) analyses inferred for 18S rDNA and cox1 showed that N. poonchensis sp. n. was nested in a separate clade.
The acanthocephalan Echinorhynchus bothniensis Zdzitowiecki and Valtonen, 1987 differs from most other species in the genus Echinorhynchus Zoega in Müller, 1776 by infecting mysids (order Mysida) instead of amphipods (order Amphipoda) as intermediate hosts. Here we report on the occurrence of E. bothniensis in mysids (Mysis segerstralei Audzijonytė et Väinölä) and in its fish definitive hosts in a high Arctic lake. Out of 15 907 sampled mysids, 4.8% were infected with a mean intensity of 1.05 worms (range 1-5), although there was notable variation between samples taken in different years and sites. Larger mysids appear more likely to be infected. Of five fish species sampled, charr,Salvelinus alpinus (Linnaeus), and a benthic-feeding whitefish morph, Coregonus lavaretus (Linnaeus), were the most heavily infected (mean abundances of 80 and 15, respectively). The adult parasite population in fish exhibited a female-biased sex ratio (1.78 : 1). Although E. bothniensis is rather unique in infecting mysids, many aspects of its natural history mirror that of other acanthocephalan species., Raija-Liisa Aura, Daniel P. Benesh, Risto Palomäki, E. Tellervo Valtonen., and Obsahuje bibliografii
The Asian neriid fly genus Telostylus Bigot (Diptera: Neriidae) is revised, including a key and illustrations of its species. Lectotype designations are proposed for four species: Telostylus babiensis de Meijere, T. decemnotatus Hendel, T. remipes (Walker) and T. trilineatus de Meijere. Two new species are described: Telostylus marshalli Sepúlveda & de Carvalho, sp. n., from Sarawak, Malaysia, and T. whitmorei Sepúlveda & de Carvalho, sp. n., from Masbate, Philippines. The morphology of Telostylus binotatus Bigot and T. remipes (Walker) is discussed in order to support their synonymy. Additionally, new country records are provided for four species: Telostylus babiensis de Meijere for Philippines, T. binotatus Bigot for Papua New Guinea, T. inversus Hennig for Malaysia and Indonesia, and T. trilineatus de Meijere for Malaysia and Philippines.
The acanthocephalan Echinorhynchus salmonis Müller, 1784 is a common parasite of salmonid fish, but it has rarely been reported from an intermediate host. Samples of benthic amphipods, Monoporeia affinis (Lindström), were taken from multiple, deep sites (usually below 70 m) in the Gulf of Bothnia over the course of more than a decade and examined for acanthocephalans. Overall, only 0.44% of 23 296 amphipods were infected, all with just a single worm. This prevalence is consistent with several previous reports of acanthocephalans in deep-water, benthic amphipods, but it appears low compared to that often reported for acanthocephalan species infecting littoral amphipods. Parasite occurrence did not exhibit a clear regional pattern (i.e. northern vs southern sites) nor did it have any relationship with site depth. At sites sampled over multiple years, parasite abundance was consistently low (mostly < 0.01), though two spikes in abundance (over 0.06) were also observed, indicating that infection can be substantially higher at particular times or in particular places. The median density of E. salmonis in samples containing the parasite was estimated as 8.4 cystacanths per m2., Daniel P. Benesh, Raija-Liisa Aura, Ann-Britt Andersin, E. Tellervo Valtonen., and Obsahuje bibliografii