Distinct parasitoid communities associated with host races of the leaf-mining moth Acrocercops transecta on distantly related host plants (Juglandaceae and Ericaceae)

Differences in host-plant species may affect the structure of parasitoid communities of phytophagous insects. Phytophagous insect species often consist of host races, and comparisons between host races enable us to infer the effects of host-plant differences on parasitoid communities. Here, we compare the parasitoid fauna of two host races of the leaf-mining moth Acrocercops transecta, which are associated with either Juglandaceae or Lyonia ovalifolia (Ericaceae). Field collection and subsequent laboratory rearing revealed a significantly higher parasitization ratio in the Juglandaceae race than in the Lyonia race. In the Juglandaceae race the majority of parasitoids were Braconidae, whereas in the Lyonia race the majority were Eulophidae. Furthermore, even within the same host race the most abundant parasitoid species differed between populations with different host associations. Hence, the present results strongly indicate that different host-plant taxa affect the structure of parasitoid communities even within a single phytophagous insect species.     

Potential host range of myrmecophilous Arhopala butterflies (Lepidoptera: Lycaenidae) feeding on Macaranga myrmecophytes

“Plant-ants”, i.e. those symbiotic with myrmecophyte plants, defend their hosts against herbivores. Plant-ants are expected to affect the host-plant ranges of herbivores that feed on myrmecophytes. This study aimed to experimentally determine whether anti-herbivore defences by plant-ants restrict the larval host-plant ranges of four Arhopala (Lycaenidae) butterflies that feed on Macaranga (Euphorbiaceae) trees, some of which are myrmecophytes. We fed Arhopala larvae with the leaves of five Macaranga species under ant-excluded conditions to examine their potential host-plant ranges. Under ant-excluded conditions, three Arhopala species survived to the pupal stage when fed species not used in the field as well as their normal host species. Our data suggested that the aggressive behaviours of plant-ants towards leaf-feeding insects restrict the potential host-plant ranges of some Macaranga-feeding Arhopala butterflies.     

Correlation of heteromorphic life instars in terrestrial Parasitengona mites and its impact on taxonomy – the case of Leptus molochinus (C. L. Koch, 1837) and Leptus ignotus (Oudemans, 1903) (Acari: Trombidiformes: Prostigmata: Erythraeidae)

Preference–performance hypothesis was tested in the butterfly Heliconius erato phyllis under field, insectary and laboratory conditions in a population from southeastern Brazil. Throughout a year, Passiflora capsularis was the host predominantly used for oviposition in the field. Similarly, when host plants were of high quality in the field, H. erato phyllis females that came from this environment laid more eggs on P. capsularis under insectary conditions. In contrast, when host plant quality declined in nature, females did not show preference for any host plant in particular in the insectary. Larvae had superior performances when reared on P. capsularis and Passiflora edulis than on Passiflora jilekii. Overall, our results show a trend towards a positive relationship between oviposition and performance in H. erato phyllis. The factors that might lead to an absence of selection under insectary conditions by females from a poor-quality environment are discussed.     

An investigation of predator‐induced defence responses in ciliated protozoa

Predator‐induced defence responses have been reported in 15 species of ciliates representing three subclasses: Hypotrichia, Stichotrichia and Hymenostomia. However, the discovery of this phenomenon in such distantly related groups suggests that it could be more widespread within the Ciliophora. In laboratory experiments, we tested 23 potential prey species with a range of potential predators including other ciliates (12 spp.), amoebae (two spp.), rotifers (two spp.), a turbellarian worm (Stenostomum sphagnetorum), and an oligochaete worm (Chaetogaster sp.). In each experiment, one predator species was incubated for 24?h with one potential prey species and the latter was examined for evidence of a defence response. One new example of predator‐induced morphological change was recorded (Euplotes viridis) and detailed observations were made for one poorly known example (E. eurystomus). Both species significantly increased their width (by about 35% and 23%, respectively) in the presence of the turbellarian worm S. sphagnetorum. An induced life cycle change was recorded for the first time among hypotrichs with E. muscorum exhibiting significantly increased rates of encystation in the presence of the ciliate predators Dileptus anser and Spathidium sp. Finally, Euplotes patella, Euplotes sp. and Stylonychia pustulata, which are usually regarded as omnivorous rather than predatory ciliates, all induced morphological change in Colpidium kleini, the C. kleini cells becoming significantly shorter and wider. No examples of induced defence response were found among groups other than hypotrichs and hymenostomes.     

Seed-feeding beetles of the weevil tribe Mecysolobini (Insecta: Coleoptera: Curculionidae) developing in seeds of trees in the Dipterocarpaceae

Species comprising two monophyletic groups of Alcidodes sensu lato (crassus group and dipterocarpi group) feed on fruits of the ecologically and economically important tropical timber family Dipterocarpaceae. Fifteen Alcidodes species are newly described from several thousand specimens of seed-feeding beetles reared from south-east Asian dipterocarp hosts (Dipterocarpoidae) and four other species are revised. Morphological keys are provided for identifying these 19 taxa. Weevil associations are provided for 70 species of Dipterocarpaceae in five genera (16 Dipterocarpus spp., four Dryobalanops spp., six Hopea spp., 39 Shorea spp. and five Vatica spp.). These records relate primarily to specimens reared from seeds in Borneo and in Peninsular Malaysia, but all known previous host records are also included (from India, Andaman Islands, Thailand, Laos, Vietnam and the Philippines) and assessed. These validated and documented host associations refute general assertions that (1) seed-eating beetles are host-specific in the tropics and (2) seed-eating beetles found on dipterocarp hosts are broad generalists across species in several genera of mast-fruiting Dipterocarpaceae. Most Alcidodes species exploit seeds from several dipterocarp species. Some Alcidodes species occur across broad geographic regions with several host species from a dipterocarp genus, other species have been found only on Bornean Hopea or Dipterocarpus species. Others, such as the two previously undescribed species feeding on Vatica species, may be restricted to separate sections of the host genus. Within an extensively sampled and diverse interspecific mast-fruiting dipterocarp community, no Alcidodes species was observed to feed on sympatric species across genera within the Dipterocarpaceae. Additional host records and specimens of Alcidodes spp. throughout the range of the Dipterocarpaceae in south and southeast Asia are required to further define these clades and the tribe Mecysolobini in general as well as to resolve the complex host associations and distributions documented.     

Distal leg morphology,subgenual organs and host detection in Stephanidae (Insecta,Hymenoptera)

The morphology of the tibia and tarsus of all legs is examined in species of two genera of Stephanidae. The subgenual organ (SGO) is examined in more detail for Megischus spp. The fore leg is the most modified in Schlettererius. In Megischus, the SGO of the hind leg is displaced to the middle of the tibia, which is swollen distad of it; in the female the hind tarsi are three‐segmented, the basitarsomere being a composite of tarsomeres 1–3. Internally, the SGO of Megischus is suspended between a spine and a ridge. In the mid and hind legs, part of the tibial wall is thinner in the region of the SGO. Our observations provide circumstantial evidence that female Stephanidae detect substrate‐borne vibrations when searching for hosts. The absence of antennal modification, as well as information on host stage targeted and general behaviour on the oviposition site indicates that they rely on noise made by the host rather than generate vibrations themselves, in contrast to Orussidae, a parasitoid wasp taxon that has been inferred to employ vibrational sounding. The external receptor elements – membranous pads versus tufts of setae – are not homologous in Orussidae and Stephanidae. A spine and ridge suspensorium of the SGO found in members of both families may represent a derived groundplan feature of the orussid–apocritan clade, with secondary modification or reduction in the latter group. Characters of the distal leg elements and the SGO suggest a basal position of Schlettererius and Stephanus within Stephanidae. Modifications of the hind tibia and tarsus in more derived members of the family indicate a shift in relative importance in vibration detection from the fore leg to the hind leg within the family.     

A biosystematic study of Aspidiotus nerii Bouché (Homoptera: Diaspididae), with the description of one new species

Summary

Uniparental (UP) and biparental (BP) populations of the oleander or ivy scale, Aspidiotus nerii Bouchè, were reared under similar conditions. Development of the UP population was always slower than that of the BP scales. UP females usually produced less than half the number of progeny the BP females had, and the patterns of development and oviposition were quite dissimilar.

The shield of UP females was slightly, but consistently, darker than that of BP females, and the latter never colonized Pittosporum undulation, the only host-plant on which UP population occur in Israel. These criteria are used to describe the uniparental population as Aspidiotus paranerii Gerson sp. nov. and to differentiate it from A. nerii. As the biology of A. paranerii clearly differs from that of a Californian uniparental sibling species of A. nerii, it is argued that the latter may have a series of such parthenogenetic relatives.     

Female treehoppers camouflage behaviour is evidenced during oviposition on wild shrubs

Various species of treehoppers possess a structure known as ‘helmet’ that may work as a camouflage feature (i.e. masquerade) by mimicking plant thorns. The helmet is expected to provide an adaptive advantage against predators if treehoppers choose to stay closer to thorns during times of vulnerability. The treehopper Enchenopa brasiliensis Strümpel possess a helmet that visually resembles the leaf thorns of its host plant, the wolf apple shrub Solanum lycocarpum St. Hill. In a field study, I examined the hypothesis that females of E. brasiliensis exhibit a potential camouflage behaviour by choosing to oviposit next to leaf thorns of S. lycocarpum. In fact, the results reveal that females of E. brasiliensis preferred to oviposit mostly on leaf midribs of S. lycocarpum possessing thorns as opposed to those without thorns. Additionally, females preferred to lay eggs closer to larger clusters of midrib thorns. This finding suggests that this oviposition/camouflage behaviour will likely increase the chances of female treehoppers being misidentified by predators; therefore, characterizing the mechanism of masquerade/deceptive resemblance. In a broader sense, this study also provides further evidence on how the narrow ecological relationships between plants and specialist herbivores can fuel the evolution of specific behavioural adaptations.     

Distribution of bisexual and unisexual species in the aphid genus Colopha Monell (Aphididae: Eriosomatinae), with the description of a new species in Japan

Aphids of the genus Colopha are represented by three bisexual and three unisexual species. The bisexual species are associated with two Ulmus species that are most closely related, being distributed disjunctively in Europe and eastern North America on the host plants. A new unisexual species of Colopha, collected from Setaria chondrachne (Poaceae) in Japan, is described under the name Colopha setaricola sp. nov. The distribution of the three unisexual species is discussed in relation to aphid‐plant associations and historical changes in the distribution of the host plants. It is suggested that these unisexual species have persisted on the secondary hosts through parthenogenetic reproduction since the extinction of the primary host plants, Ulmus species section Blepharocarpus. Therefore, the unisexual species in Colopha exemplify Mordvilko's hypothesis that unisexual species on the secondary host plants have remained as relics in the region where the primary host was once distributed but then became extinct.     

Geographic distribution,host plants,and morphological variation of the currently radiating phytophagous ladybird beetle Henosepilachna diekei

To overview the morphological and ecological diversification within a species of phytophagous ladybird beetle Henosepilachna diekei, information concerning its distribution and host plant use was studied. This species was found widely in South East and South Asia from the Philippines through the Greater Sunda islands, a western part of Lesser Sundas, the Malay Peninsula to Sri Lanka. Mikania species (Asteraceae), Mikania micrantha in particular, were the most frequently used host plants, but some other plants belonging to Lamiaceae or Acanthaceae were also used by some local populations. Each population is possibly monophagous. According to morphological analyses, seven populations from four host plants at six sites on four Indonesian islands were grouped into two, one occurring on Java and Kalimantan (Borneo) and another on Sulawesi and Lombok, indicating that they were separated by the Wallace line. This morphological distinction was not correlated with the host plant use.     

Identification and characterization of Biomphalaria peregrina (Orbignyi, 1835) from Agua Escondida in northern Patagonia,Argentina

During a general malacological survey for freshwater gastropods in northern Patagonia, a population of Biomphalaria was encountered at Agua Escondida. Biomphalaria spp. are freshwater pulmonates of biomedical importance, uncommon in Mendoza Province, and often act as intermediate hosts for Schistosoma mansoni. By looking at both morphological and molecular characters, we describe a detailed process of identification and characterization of Biomphalaria peregrina from a location towards the extremity of its species range. A reference DNA ‘barcode’ is presented. As B. peregrina has been shown to be a permissive experimental host of S. mansoni, snails were also screened in the field for schistosomiasis and later in the laboratory using a novel polymerase chain reaction-based assay but no infections were found. Considering the transmission potential of this species, increased vigilance for intestinal schistosomiasis is recommended, especially if local environmental conditions become favourable for disease transmission, for example, through future climate change and intensification of irrigation.     

Description of the biology and immature stages of Pagyris ulla (Hewitson) (Lepidoptera: Nymphalidae: Ithomiini) in the Colombian Andes

The biology and immature stages of Pagyris ulla (Hewitson, [1857]) (Lepidoptera: Nymphalidae: Ithomiini) are described for the first time. The species’ host plant is established to be Brugmansia candida Pers. (Solanaceae). The life cycle from eggs to adult under laboratory conditions and ambient temperature took approximately 47 days, and the larvae passed through five instars. The larvae are gregarious, feed at night, and rest during the day in nests made by joining leaves near the apex of the plant stem.     

Asymmetric larval competition between two species of neotropical foam‐nesting frogs: Leptodactylus fuscus and Engystomops pustulosus

Larval competition was investigated in foam‐nesting frogs with contrasting breeding strategies. Leptodactylus fuscus nests in burrows with moderate numbers of large eggs, mainly on dry nights; Engystomops pustulosus makes floating nests with large numbers of small eggs, mainly on wet nights. Both use the same temporary pools in open habitat over an extended breeding season. Larval growth to metamorphosis was assessed in a semi‐natural experiment and in the laboratory. Tanks contained either single species or equal numbers of both species. Inter‐specific competition was asymmetric; L. fuscus survived as well as or better in competition with E. pustulosus than in intra‐specific competition. Leptodactylus fuscus attained larger sizes with E. pustulosus present. In interspecific competition E. pustulosus showed worse survival and grew slower and to a smaller size. Outdoors, both species tolerated water temperatures that often rose to 42°C and reached metamorphosis in very short times: 14 days after oviposition in L. fuscus and 17 days in E. pustulosus.     

The polymorphism of a lygaeid bug Oxycarenus (Oxycarenus) multiformis Samy

Summary

The new species Oxycarenus (Oxycarenus) multiformis Samy has been found to be a polymorphic species. Four colour forms have been found: red, banded, spotted and black. Breeding experiments under laboratory conditions have indicated that dominance is nearly complete in the order given and that the second generation is segregated in the 3:1 ratios.

These colour forms have been given the taxonomic status of a single species on the basis of: (a) identical measurements of external characters, (b) similar morphological characters in the male genitalia, (c) equal fertility of each form, (d) free interbreeding, (e) random mating, (f) occupation of the same geographical regions, and (g) host plant relationship.     

A new species of the Neotropical genus Beebeomyia (Diptera: Richardiidae) with observations of its biology on Dieffenbachia oerstedii (Araceae)

A new species of the genus Beebeomyia Curran found in central Veracruz (Mexico) is described, including characters of the male and female terminalia, and a key to the identification of the known species is provided. This new species was found feeding within inflorescences of Dieffenbachia oerstedii Schott (Araceae). Larvae were found throughout the inflorescence, with a proportion nearly three times higher in the female (bottom) than the male (top) section. The life cycle from larval stage to adult emergence takes place in an average time of 42 days, while pupation occurs within the inflorescence. Observations of the oviposition behaviour suggest that after oviposition, the female marks the inflorescence with a deterrent pheromone to prevent further ovipositions by other conspecific females.

http://zoobank.org/lsid:zoobank.org:pub:DC19F7E5-3AAF-4E5C-A35C-F4872C89D3B4     

Gastrointestinal helminths of eleven species of Emoia (Squamata: Scincidae) from Papua New Guinea

Four hundred and forty‐six individuals representing 11 species of Emoia (Scincidae), E. atrocostata, E. battersbyi, E. caeruleocauda, E. impar, E. jakati, E. kordoana, E. longicauda, E. obscura, E. pallidiceps, E. physicae and E. popei, collected in Papua New Guinea were examined for helminths. Two species of Cestoda (Adenobrechmos greeri, Cylindrotaenia hickmani); five species of Digenea (Mesocoelium monas, Paradistomoides gregarium, Saurokoilophilia kinsellai, Spelotrema brevicaeca, Zeylanurotrema sphenomorphi); 14 species of Nematoda, (gravid individuals of Abbreviata oligopapillata, Hedruris hanleyae, Kreisiella chrysocampa, Maxvachonia adamsoni, Meteterakis crombiei, Parapharyngodon maplestoni, Physaloperoides milnensis, Pseudoreticularia dipsarilis, Raillietnema nanus, Skrjabinodon sp. 1, Skrjabinodon sp. 2 and larvae (in cysts) of Abbreviata sp., Acuariidae gen. sp., and Riticulariidae gen. sp.) were found. The mean helminth species richness for infected skinks was 6.4±4.7 SD (range 1–14 species). Fifty‐three new host records are reported.     

Reproductive biology and strategies of nine meloid beetles from Central Europe (Coleoptera: Meloidae)

The reproductive biology of meloid species from Central Europe is investigated by means of laboratory breeding experiments. They show that the total reproductive potential of meloids, with up to 40,000 eggs, largely exceeds prior data. Furthermore, the number of laid eggs strongly relates to the way by which the triungulins find their host. Clutch size correlates significantly with the size of the beetle, while egg size is independent of this. Both clutch size and egg size decrease with each oviposition. For some species, reproductive data are used to demonstrate how they have adapted to their habitat and to point out existing trade‐offs. Based on the obtained results and on an evaluation of the relevant literature, three types of reproductive strategy can be distinguished within the meloids: (1) very high reproductive rates of open field species with phoretic larvae; (2) average reproductive rates of forest populations of species with phoretic larvae and of species the larvae of which search the nests of their hosts actively; and (3) small to average reproductive rates of those species depositing their clutches in the immediate proximity of their hosts' nests.     

Attachment site selection of Hydrachna and Eylais (Acari: Hydrachnellae) watermite larvae infecting Corixidae (Hemiptera: Heteroptera)

The sites of attachment of four larval watermite species were recorded from four corixid species in Lough Corrib, Ireland. Parasitic watermites exhibited preferences in respect of attachment sites on the corixid hosts and these patterns were consistent for all host species examined. Hydrachna cruenta utilized areas of the host which were in direct contact with the water, the distribution of larvae reflecting the general behaviour and microdistribution of the hosts. Hydrachna conjecta infected the ventral hemielytra with a significant asymmetrical distribution on the right hemielytron, resulting from the folding pattern of the hemielytra and the larval route of entry to the subhemielytral air space. Eylais species attached to the abdominal terga of the host, E. infundibulifera infecting the anterior two terga and E. discreta terga three and four. Cymatia bonsdorffi was not parasitized by E. infundibulifera and on this host the majority of E. discreta attached to the second abdominal tergite. Eylais species infecting small corixid hosts may avoid interference competition with H. conjecta by attaching to the left side of the abdomen. Attachment site selection may contribute towards alleviation of intraspecific and interspecific interference competition for larval growing space.     

Larval feeding habits of the Hepialidae (Lepidoptera)

The host-plant relationships of the Hepialidae are discussed in relation to host range and larval tunnelling behaviour. Larvae are mostly phytophagous on live angiosperms, gymnosperms, pteridophytes and mosses. Generally they specialize as feeders of leaf, stem/branch or root tissue, but dietary transitions from leaf to stem and root to stem occur in some species. An early period of mycophagy where larvae feed on fungi or dead decaying plant tissue is recorded in a wide range of species that feed on live embryophytes in later instars. Feeding patterns of the Hepialidae are compared with those of other major lepidopteran taxa and the evolutionary implications of hepialid feeding habits for the origin and derivation of larval host-plant relationships in Lepidoptera are discussed. It is suggested that the developmental transition from mycophagy to phytophagy in the Hepialidae is the result of partial ‘suppression’ of mycophagy in the generalist feeding ancestor of Lepidoptera.