Gill monogeneans of neotropical cichlid fish: diversity,phylogenetic relationships,and host-parasite cophylogenetic associations

Host-parasite coevolution is one of the main topics of the evolutionary biology of host-parasite associations. The majority of monogeneans parasitizing fish exhibit a high degree of host specificity. As a result, their evolutionary history might be intertwined with that of their fish hosts. The Cichlidae represent a diverse group of secondary freshwater fish with disjunctive distribution. Host-specific dactylogyrid monogeneans commonly parasitize cichlid fish. Their high diversity is associated with the main areas of cichlid distribution, i.e., Neotropical America and Africa. Nevertheless, the parasite fauna of cichlids from Neotropical America is still underexplored. A total of 31 cichlid species were examined for the presence of monogeneans, with 20 of them being parasitized. On these cichlids, 30 monogeneans belonging to the genera Gussevia, Trinidactylus, and Scadicleithrum were identified, 17 of them potentially representing new species for science. Phylogenetic analyses revealed three monophyletic groups of Neotropic cichlid monogeneans. Genus Gussevia was monophyletic, while Sciadicleithrum resulted polyphyletic. Sciedicleithrum from South America and Sciadicleithrum from Mexico represented two divergent lineages. The plesiomorphic Neotropical cichlid host group for dactylogyrid monogeneans was Cichlini, from which the representatives of other Neotropical cichlid tribes were colonised. Cophylogenetic analyses revealed a statistically significant cophylogenetic signal in the investigated host-parasite system, with host switch and duplication representing the main coevolutionary events for monogeneans parasitizing Neotropical cichlids. This scenario is in accordance with previous studies focussed on dactylogyridean monogeneans parasitizing freshwater fish in Europe and Africa.     

Transmission as a predictor of ecological host specificity with a focus on vertical transmission of microsporidia

Consideration of vertical transmission is particularly important for understanding the life cycles of entomopathogens that are naturally occurring in invertebrate populations, are a problem in beneficial insect colonies, or are under consideration as classical biological control agents. Empirical studies generally corroborate the evolutionary hypothesis that virulence should be relatively low for pathogen species that utilize vertical transmission as one mechanism for maintenance in the host population. Nevertheless, many entomopathogens with significant effects on host populations are vertically as well as horizontally transmitted. In addition to gaining a better understanding of pathogen-host interactions and population dynamics, studies of the host range and specificity of putative biological control agents can benefit by using transmission studies to better predict ecological host specificity from physiological data. Horizontal transmission requires a tightly organized host-pathogen relationship to succeed, but still involves, albeit restricted by host behavior and pathogen dosage, the physiological susceptibility of the nontarget host. Vertical transmission studies can provide increased stringency for determining the ecological host specificity of a species and may be one very accurate predictor of the ability of a pathogen to successfully host-switch when introduced into a na?ve population.     

Bathymetric distribution and diversity of deep water polychaetous annelids in the Sigsbee Basin, northwestern Gulf of Mexico

The deep water polychaete fauna is analyzed in this study particularly regarding its composition and variations with depth in the Sigsbee Basin, northwestern region of the Gulf of Mexico. Samples were taken at 10 stations along a bathymetric gradient with depth ranges from 200 to 3760 m with a USNEL (0.25 m²) corer. A total of 287 individuals were identified, from 21 families and 65 species. The most important families, both in terms of abundance and species richness, were: Paraonidae (65.4 ind./0.25 m², 9 spp.), Cirratulidae (28.93 ind./0.25 m², 7 spp.) and Spionidae (18.07 ind./0.25 m², 7 spp.). In general, density tended to decrease with depth with minima at around 2000 m, although two abundance peaks were detected at 3700 and 3760 m, making the pattern seem an inverted parabolic curve. The Shannon-Wiener diversity values varied from 0.54–0.92 at around 2000 m to 3.39 at 3620 m and 3.34 at 3760 m. These results contrast with what is already reported from the North Atlantic and the Tropical Pacific deep benthic communities, where highest diversities are found at 2000 m. Faunal changes evaluated through Beta Diversity (0.08–0.1) and the low similarity found between the stations, emphasized the high variability in the composition of the fauna in the Sigsee Basin, meaning that the faunal composition is practically different at all the sampling stations. Ten species are newly recorded for the Mexican fauna.     

Salinity and nutrients in a tropical coastal lagoon with groundwater discharges to the Gulf of Mexico

This study described the nutrient dynamics in a tropical coastal lagoon that is affected by the infiltration of cold nutrient-rich groundwater. The spatial and time variation of physicochemical characteristics (e.g., temperature, salinity, oxygen) and nutrients (e.g., nitrate, ammonium, soluble reactive silicate, soluble reactive phosphorus) are depicted and show changes with respect to weather conditions. The lagoon shows a permanent salinity gradient from the inner zone (14–19). Nitrate and soluble reactive silicate (SRSi) are inversely correlated with salinity. Soluble phosphorus (SRP) shows highest levels in the inner zone during winter months (>9 µM). Ammonium shows two high peaks, one in the rainy season (15 µM) and the other during winter (11 µM). The intensity and quality of rainfall influences the nitrate and SRSi inputs, while biological activity influences the SRP and ammonium levels.     

Characterization of a toxic Pseudo-nitzschia spp. bloom in the Northern Gulf of Mexico associated with domoic acid accumulation in fish

A toxic bloom of Pseudo-nitzschia spp. was observed in the Alabama coastal waters of the northern Gulf of Mexico (NGOM) in June 2009 that resulted in the accumulation of domoic acid (DA) in fish. The bloom initiated following a large storm event that likely caused increased groundwater discharge 16–20 days prior to peak densities. Eleven sites, located in littoral shoreline waters and inshore embayments spanning the entire Alabama NGOM coastline, were sampled during peak densities to assess Pseudo-nitzschia species composition and toxicity, and associated water-quality parameters. Small fish (0.27–11.9 g body weight) were collected at six of these sites for analysis of DA content. High Pseudo-nitzschia spp. densities (8.27 × 10⁴–5.05 × 10⁶ cell l⁻¹) were detected at eight sites located in the littoral shoreline and particulate DA was detected at six of these littoral sites (48.0–540 pg ml⁻¹). The bloom consisted primarily (>90%) of Pseudo-nitzschia subfraudulenta, a species previously characterized as forming only a minor component of Pseudo-nitzschia assemblages and not known to produce DA. Pseudo-nitzschia spp. were at low densities or not detected at the inshore sites and DA was detected at these sites. Pseudo-nitzschia spp. density varied along an estuarine gradient, with greater densities occurring in the most saline, clear, and nutrient-poor waters. Cell density was strongly and negatively correlated with silicate (Si) concentrations and the ratios of silicate to dissolved inorganic nitrogen and phosphate (Si:DIN and Si:PO₄). Cell toxin quota was negatively correlated with phosphate, and strongly and positively correlated with the ratio of total nitrogen to total phosphorus (TN:TP). These relationships are consistent with previous observations that indicate Pseudo-nitzschia spp. density and toxicity are likely to be greater in high salinity, high irradiance, and nutrient-poor waters. DA was detected in 128 of 131 (98%) of the fish collected, which included seven primary and secondary consumer species. This is the first demonstration of trophic transfer of DA in this region of the NGOM, indicating that toxic blooms of Pseudo-nitzschia spp. in Alabama coastal waters have the potential to transfer DA to recreationally and commercially important fish species.     

Host-ectoparasite associations; the role of host traits,season and habitat on parasitism interactions of the rodents of northeastern Iran

Rodents play a significant role as reservoirs of zoonotic diseases. Nevertheless, in general their ectoparasite assemblage and host-ectoparasite associations are poorly known. This study intended to provide new insights into the relationships between ectoparasites and rodents in northeastern Iran. Rodents were captured using live traps during the years 2016–2020, and their ectoparasites were collected. Parasitological indices such as infestation rate, prevalence and mean intensity of infestation were analyzed. A total of 284 rodents, belonging to 17 species, were trapped and found to be infested by 178 ectoparasites from five orders Siphonaptera, Phthiraptera, Ixodida, Mesostigmata and Trombidiformes. The overall infestation rate was 50.3%. The flea Nosopsyllus fasciatus and the louse Polyplax asiatica dominated among all fleas and lice, respectively. Haemaphysalis punctata and Haemolaelaps sp. were recorded as the most abundant tick and mite, respectively. Nosopsyllus fasciatus exhibited low and Polyplax asiatica moderate host specificity. Approximately 64.2% of ectoparasites shared more than one host, and others were singletons. Seasonal fluctuations were found in the occurrence of ectoparasite; fleas and lice were more abundant in spring and winter, respectively. Ticks demonstrated high abundance in spring and summer and mites were more common in autumn. The overall prevalence of ectoparasite on male rodents was greater than that on females (56.4% vs. 44.4%), while similar mean intensities were detected for both sexes. This study extends the knowledge on the distribution, seasonality and host choice of four main groups of ectoparasites in association with rodents. Further studies are needed to provide deep insight into how relationships and interactions between ectoparasite and rodents are formed, and how they can be applied in epidemiology.     

Characterization of 13 microsatellite loci for the deep-sea coral, Lophelia pertusa (Linnaeus 1758), from the western North Atlantic Ocean and Gulf of Mexico

A suite of 13 polymorphic tri- and tetranucleotide microsatellite loci were isolated from the ahermatypic deep-sea coral, Lophelia pertusa. Among 51 individuals collected from three disjunct oceanic regions, allelic diversity ranged from six to 38 alleles and averaged 9.1 alleles per locus. Observed heterozygosity ranged from 9.1 to 96.8% and averaged 62.3% in the Gulf of Mexico population. For some loci, amplification success varied among collections, suggesting regional variation in priming site sequences. Four loci showed departures from Hardy-Weinberg equilibrium in certain collections which may reflect nonrandom mating.     

Interaction of a solitary larval endoparasitoid, Microplitis mediator, with its host, Mamestra brassicae: host acceptance and host suitability

Abstract:  Microplitis mediator (Haliday) (Hym., Braconidae) is an important parasitoid of early instar larvae of the European cabbage moth, Mamestra brassicae L. (Lep., Noctuidae). In the laboratory, we examined attack responses of female M. mediator to the first three larval instars of M. brassicae . Females were presented with M. brassicae larvae either one individual at a time in a no-choice experiment, or three individuals, one from each instar, simultaneously in a choice experiment. Whether or not there was choice, naïve female parasitoids attacked a high proportion of larvae and did not discriminate among instars. In the no-choice experiment, attacked larvae were reared, and parasitoid cocoons were produced from about 76% of larvae attacked as first and second instars, but from only 19% of larvae attacked as third instars. Dissections of attacked larvae from the choice experiment showed that about 79% of attacks on first and second instars resulted in oviposition compared with only 49% for third instars. When given choice, frequency and number of attacks on first instar larvae increased with increasing parasitoid experience. Our results suggest that first and second instar larvae of M. brassicae are suitable hosts for M. mediator , but that third instar larvae are suboptimal both because oviposition attempts were frequently unsuccessful and because immature parasitoids failed to complete development. Nevertheless, naïve attacking parasitoids exhibited minimal discrimination among instars, although experienced parasitoids most frequently attacked first instar larvae. The host selection behaviour of M. mediator is discussed in the context of optimal foraging theory and implications for biological control.     

Influence of host plant-derived and abiotic environmental parameters on the composition of the diazotroph assemblage associated with roots of Juncus roemerianus

Environmental factors governing the distributions of plant root-associated bacteria are poorly understood. Most plant species occurring in salt marsh estuaries are restricted to very specific habitats within the marsh and plant-derived and abiotic environmental features covary. We examined diazotrophic bacteria inhabiting the rhizoplanes of different populations of the black needlerush, Juncus roemerianus , growing in two different habitats, in order to examine the relative influence of plant-derived and abiotic environmental parameters on diazotroph assemblage composition. Juncus roots were collected from a monotypic Juncus patch in the low intertidal marsh, and from the main monotypic Juncus stand in the high marsh. A total of 235 bacterial pure cultures were isolated from the roots using combined nitrogen-free media. Physiologically similar strains were grouped, producing 58 different groups. Strains representing 49 of these groups tested positive for nifH , and substrate utilization profiles of these strains were compared quantitatively. Three major substrate utilization clusters were identified and all contained both Juncus patch and main stand isolates. Denaturing gradient gel electrophoresis analysis of nifH amplicons recovered from roots and from vegetated sediments taken from the main stand and from two patches was also performed. Juncus root nifH amplicon profiles from all three sampling sites were very similar. Profiles of amplicons from vegetated sediments were also similar across sites, but less similar than the root profiles. Results from two independent methodological approaches indicated a strong impact of the plant host relative to that of the abiotic environment on the composition of the root-associated diazotroph assemblage.     

Studies on Anoplotaenia dasyuri Beddard, 1911 (Cestoda: Taeniidae), a parasite of the Tasmanian devil: Observations on the egg and metacestode

The ultrastructure and hatching mechanisms of the egg of Anoplotaenia dasyuri showed minor differences from those of other taeniid species. The embryophore disintegrated under the action of pepsin, but activity of the embryo did not occur until placed in an alkaline solution containing pancreatin. The addition of bile from various host species did not affect the hatching of eggs of A. Daysuri although it did increase the rate of hatching of eggs of Taenia pisiformis. Metacestodes were recovered from the hearts of experimentally infected possums (Trichosurus vulpeculd), kangaroos (Macropus giganteus and M.fuliginosus) and from the livers of mice and guinea pigs fed eggs of A. Daysuri. A wombat (Vombatus ursinus), rats and rabbits could not be infected orally. Hatched and activated embryos, injected intravenously, developed in the hearts of kangaroos and wallabies (M. rufogriseus), the livers, lungs, kidneys and hearts of mice, but not at all in rats and rabbits. Similarly, injections of embryos into the portal veins of mice, rats and rabbits resulted in development of metacestodes in the lungs and liver of mice only. The development of some stages of the metacestode are briefly described and the possible phylogeny of the parasite discussed.     

Characterization and evaluation of Ramularia crupinae,a candidate for biological control,and of its host,two varieties of Crupina vulgaris in the United States

Crupina vulgaris (common crupina) is an invasive annual plant of rangelands and pastures in the United States (USA). There are two varieties of C. vulgaris in the USA that differ morphologically and biologically, particularly in requirements for bolting. A vernalization protocol enabled synchronization of bolting, thus facilitating concurrent comparative studies of both varieties. Leaf-removal experiments suggest that all leaves provide photosynthate for seed fill, but the cauline leaves, on a relative basis, produced 1.7–4 times more seed per g than rosette leaves, suggesting disease on the cauline leaves has greater potential to reduce seed production than disease on rosette leaves. Ramularia crupinae, a leaf-spotting fungus, was evaluated for biological control. A single inoculation caused a 47% reduction in root dry weight, and seed yield was reduced by 39% as the number of inoculations increased from 0 (controls) to 3. None of 35 non-target taxa, i.e., species, cultivars, and varieties, in the tribe Cardueae was damaged from inoculation by R. crupinae, including safflower, which developed a few, small necrotic spots on old leaves. Best Linear Unbiased Predictors (BLUPs), generated by a mixed model analysis of disease reaction and genetic relatedness data, indicated that only C. vulgaris varieties were susceptible to disease; i.e., BLUPs were significantly different from zero (p > |t| < 0.05). None of the other taxa had BLUP estimators that were significantly different from zero and were, therefore, determined to be not susceptible to disease by R. crupinae. Results suggest that R. crupinae is a potentially good candidate for biological control of this important weed pest and would likely not affect other species of importance in the USA.     

A new species of Amphictene (Annelida,Pectinariidae) from the Gulf of Mexico,with a redescription of Amphictene guatemalensis (Nilsson, 1928)

The genus Amphictene is reported for the first time from Mexico. Previous records for America are restricted to Brazil (Amphictene catharinensis) (Grube, 1870), and Guatemala (Amphictene guatemalensis) (Nilsson, 1928). In this paper we describe a new species, Amphictene helenae sp. n., characterized by the presence of three pairs of tentacular cirri, while other species have only two pairs. The new species is closely similar to Amphictene catharinensis, and can be distinguished by the presence of a circular group of glandular papillae inserted between the lines of glandular cirri present from the second segment. Amphictene guatemalensis is redescribed based on type material; it differs from the new species in the presence of two pairs of tentacular cirri on segments 1 and 2, six pairs of glandular cirri on the third segment, and four glandular lobes fused in pairs on the fourth segment.     

Influence of aphid size,age and behaviour on host choice by the parasitoid wasp Ephedrus californicus: a test of host-size models

Summary When host quality varies, parasitoid wasps are expected to oviposit selectively in high-quality hosts. We tested the assumption underlying host-size models that, for solitary species of wasps, quality is based on host size. Using Ephedrus californicus, a solitary endoparasitoid of the pea aphid, we evaluated the influence of aphid size (= mass), age and defensive behaviours on host selection. Experienced parasitoid females were given a choice among three classes of 5-day-old apterous nymphs: small aphids that had been starved daily for 4 h (S4) and 6 h (S6) respectively, and large aphids permitted to feed (F) normally. Wasps attacked more, and laid more eggs in, small than large aphids (S6>S4>F). This rank-order for attack did not change when females could choose among aphids of the same size that differed in age; however, wasps oviposited in all attacked aphids with equal probability. Host size did not influence parasitoid attack rates when aphids were anaesthetized so that they could not escape or defend themselves. As predicted by host-size models, wasp size increased with host size (F>S4; S6), but large wasps required longer to complete development than their smaller counterparts (S4E. californicus reflects a trade-off between maximization of fitness gains per egg and the economics of search-time allocation. Because large aphids are more likely to escape parasitization, a wasp must balance her potential gain in fitness by ovipositinng in a high-quality (large) aphid against her potential cost in terms of lost opportunity time if the attack fails.     

Growth and development of a generalist insect herbivore, Operophtera brumata, on original and alternative host plants

A generalist feeding strategy is common among eruptive insect herbivores but the ultimate reasons for a generalist strategy are not clear. Although generalist insect herbivores are able to complete their life cycle on several species of host plants, there is wide variation in the performance of individuals grown on different hosts. We examined whether different populations of Operophtera brumata are adapted to use the host species which is locally most abundant, and how the host plant affects growth and development of the insect. We reared two allopatric populations (eastern Finland, Prunus padus; south-west Finland, Quercus robur) on four species of host plants (Pr. padus, Populus tremula, Q. robur, Salix phylicifolia) from neonate larvae to the adult stage and measured the growth and development of individuals and the timing of adult hatching. The performance of both populations was best on Pr. padus, and the south-western population, originally on Q. robur, was well adapted to this host. The host affected the growth of females more than that of males. The host plant had an unexpected effect on hatching times of the adults. Individuals grown on the original host hatched in normal synchrony, i.e. males 6–7 days before females; but on alternative hosts this synchrony was disturbed. As is common in eruptive, capital-breeding generalist moths where female fecundity is linked to weight, host quality is critical for the flightless females of O. brumata. We suggest that in a heterogeneous environment the disturbing effect of alternative host plants on adult emergence may decrease the population density and growth rate compared to the potential maximum in a homogeneous environment. Received: 8 July 1999 / Accepted: 29 October 1999     

A new species of baleen whale (Balaenoptera) from the Gulf of Mexico,with a review of its geographic distribution

Bryde's-like whales are a complex of medium-sized baleen whales that occur in tropical waters of all three major ocean basins. Currently, a single species of Bryde's whale, Balaenoptera edeni Anderson, 1879, is recognized, with two subspecies, Eden's whale, B. edeni edeni and Bryde's whale, B. edeni brydei (Olsen, 1913), although some authors have recognized these as separate species. Recently, a new, evolutionarily divergent lineage of Bryde's-like whale was identified based on genetic data and was found to be restricted primarily to the northern Gulf of Mexico (GOMx). Here, we provide the first morphological examination of a complete skull from these whales and identify diagnostic characters that distinguish it from the other medium-sized baleen whale taxa. In addition, we have increased the number of genetic samples of these Bryde's-like whales in the GOMx from 23 to 36 individuals, all of which matched the GOMx lineage. A review of Bryde's-like whale records in the Caribbean and greater Atlantic supports an isolated distribution for this unique lineage, augmenting the genetic and morphological body of evidence supporting the existence of an undescribed species of Balaenoptera from the Gulf of Mexico.     

Meligethes aeneus oviposition preferences,larval parasitism rate and species composition of parasitoids on Brassica nigra,Raphanus sativus and Eruca sativa compared with on Brassica napus

The trap crop strategy is based on host plant discrimination by pests and their parasitoids, which may respond differently to various host plant cues, thus affecting their respective population distributions. We conducted a three-year study to compare the responses of the most damaging pest of oilseed rape (Brassica napus L.), the pollen beetle (Meligethes aeneus Fab.), and its hymenopteran parasitoids to various potential trap crops: Brassica nigra L., Raphanus sativus var. olifera Pers. and Eruca sativa Mill. with that to B. napus. We recorded their abundance, oviposition preferences and the species composition of the parasitoids.Our results show that oviposition rates of the pollen beetle and its parasitoids as well the species composition of the parasitoids varies with plant species. We discuss the potential of these plant species, especially B. nigra, to enhance the natural control of the beetle by fostering several parasitoid species. The species composition of the parasitoids on different host plants compared with on B. napus is presented for the first time. In addition to trapping pests, the trap crops could also act as parasitoid banks, enhancing natural control of the pest through providing suitable hosts for natural enemies, without increasing the population growth of the next generation of pests.     

Elevated seasonal temperature disrupts prooxidant-antioxidant homeostasis and promotes cellular apoptosis in the American oyster,Crassostrea virginica,in the Gulf of Mexico: a field study

One of the major impacts of climate change has been the marked rise in global temperature. Recently, we demonstrated that high temperatures (1-week exposure) disrupt prooxidant-antioxidant homeostasis and promote cellular apoptosis in the American oyster. In this study, we evaluated the effects of seasonal sea surface temperature (SST) on tissue morphology, extrapallial fluid (EPF) conditions, heat shock protein-70 (HSP70), dinitrophenyl protein (DNP, an indicator of reactive oxygen species, ROS), 3-nitrotyrosine protein (NTP, an indicator of RNS), catalase (CAT), superoxide dismutase (SOD) protein expressions, and cellular apoptosis in gills and digestive glands of oysters collected on the southern Texas coast during the winter (15 °C), spring (24 °C), summer (30 °C), and fall (27 °C). Histological observations of both tissues showed a notable increase in mucus production and an enlargement of the digestive gland lumen with seasonal temperature rise, whereas biochemical analyses exhibited a significant decrease in EPF pH and protein concentration. Immunohistochemical analyses showed higher expression of HSP70 along with the expression of DNP and NTP in oyster tissues during summer. Intriguingly, CAT and SOD protein expressions exhibited significant upregulation with rising seasonal temperatures (15 to 27 °C), which decreased significantly in summer (30 °C), leaving oysters vulnerable to oxidative and nitrative damage. qRT-PCR analysis revealed a significant increase in HSP70 mRNA levels in oyster tissues during the warmer seasons. In situ TUNNEL assay showed a significant increase in apoptotic cells in seasons with high temperature. These results suggest that elevated SST induces oxidative/nitrative stress through the overproduction of ROS/RNS and disrupts the antioxidant system which promotes cellular apoptosis in oysters.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12192-021-01232-2.     

Biology,host range and varietal preference of the leaf-feeding geometrid, <Emphasis Type="Italic">Leptostales ignifera</Emphasis>, a potential biocontrol agent for <Emphasis Type="Italic">Lantana camara</Emphasis> in South Africa,under laboratory conditions

Lantana camara L. (Verbenaceae) is a weed of major importance in South Africa. It invades indigenous forests and veld, valuable commercial and agricultural forests, plantations and orchards, as well as river-catchment areas. Several natural enemies, including insect and pathogen species, have been released in South Africa, some of which established successfully. These do not exert sufficient control and additional natural enemies are required. Leptostales ignifera Warren (Lepidoptera: Geometridae), one of several new species being investigated as potential biocontrol agents, was collected in the subtropical parts of Florida, USA and Mexico. Host specificity trials indicated L. camara to be the preferred host plant of this quick-developing, voracious leaf-feeder, with some of the African indigenous Lippia species qualifying as very marginal hosts. The possible preference that L. ignifera might have for different South African naturalized L. camara varieties was studied during quarantine laboratory preference trials. Variety 029WP was the most suitable host for L. ignifera, although the other four tested varieties were able to support viable populations of the insect. Not taking other abiotic and biotic factors such as climate and predation into consideration, once released, L. ignifera should be able to establish on all five of the tested varieties in the field and contribute to the biological control of the complex of L. camara as a whole. Based on the above studies, permission has been granted for the release of L. ignifera in South Africa.     

A review of host plants of Callipogon (Eoxenus) relictus Semenov (Coleoptera: Cerambycidae: Prioninae), a Korea natural monument,with a new host,Quercus aliena Blume

A comprehensive checklist identifying host plants of phytophagous insects are essential in protecting forest ecosystems from major insect pests. We investigated host plants of Callipogon (Eoxenus) relictus Semenov (Coleoptera: Cerambycidae: Prioninae), an insect categorized as a natural monument in South Korea. Field surveys in Gwangneung forest led us to newly recognize the oriental white oak, Quercus aliena Blume (Fagaceae), as a host plant of C. (E.) relictus. Based on this result and a literature search, we provide an updated list of host plants of C. (E.) relictus in the present study. In addition, we also discussed about microorganisms (mushrooms) and habitats in Gwangneung forest (South Korea) and Ussurisky Nature Reserve (Russia) that are relevant to C. (E.) relictus.     

Intra-plant host selection, oviposition preference and larval survival of Chrysophtharta agricola (Chapuis) (Coleoptera: Chrysomelidae: Paropsini) between foliage types of a heterophyllous host

Abstract 1 Paropsine chrysomelid beetles defoliate commercial eucalypt plantations in Australia. Adults and larvae feed on the same host, with the larval food source determined by the oviposition choice of females. Most eucalypt species are heterophyllous, with their foliage undergoing distinct morphological and chemical changes between adult and juvenile growth. 2 The intra‐plant foliage feeding and oviposition preference adults and the larval development of Chrysophtharta agricola were examined using adult and juvenile foliage of a heterophyllous plantation species, Eucalyptus nitens. The foliage types differ in chemistry, toughness, waxiness and timing of production. 3 In the field, feeding damage caused by adult beetles was 15% more frequent on adult foliage than on juvenile foliage; however, egg batches were three times more common on juvenile than on adult foliage. 4 Oviposition preference for juvenile foliage over adult foliage was confirmed in choice trials in the laboratory, with adult fecundity and longevity not significantly different between foliage types. 5 Larval survival, development time and subsequent pupal weight were also unaffected by foliage type, suggesting that neither foliage type is nutritionally superior for adults or for larvae. However, adult foliage was significantly thicker than juvenile foliage and this may prove a physical constraint to larval establishment. Biotic and abiotic factors (including interactions with natural enemies, competition, microclimate and mate location) that may affect patterns of host plant utilization are discussed.