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At least 577 records · Page 32Linked to original sources
PubMed1993

Mites (ACARI) occurring on Geotrupes spiniger Marsh. and G. Stercorarius (L.) (Insecta, Scarabaeidae) in Poland.

694 mites belonging to 16 species were collected from 67 specimens of G. spiniger and 2314 mites belonging to 17 species were collected from 118 specimens of G. stercorarius. The most common were the following species: Alliphis halleri, Macrocheles glaber, Scarabaspis inexpectatus and Scamaphis equestris. Macrocheles scutatus, Glyptholaspis americana and Parasitus consanguineus are new for the Polish fauna.

Animals↗
PubMed1975

[Juvenile hormone activity in healthy and parasitized adult Anacridium aegyptium (Insecta, Orthoptera) during and after experimental termination of diapause].

The content of juvenile hormone in the haemolymph of Anacridium, normal and infected by Metacemyia (Diptera Tachinidae), has been evaluated by the Galleria bioassay. In all the diapausing locusts, the level of juvenile hormone is very low. It is slightly increased in the males and the parasited animals. In all the locusts,, activated by electrostimulations of the pars intercerebralis, the level of juvenile hormone is high. It is the highest in the infected females with an inhibited vitellogenesis. The allata system cannot therefore be implicated in parasitic castration.

Animals↗
PubMedDate not supplied

[Comparative study of the susceptibility of 5 triatomine species (Insecta: Reduviidae) to Trypanosoma cruzi infection].

In order to determine the most suitable species of triatomine for xenodiagnosis of the Chagas disease, five species triatomine (Triatoma barberi, T. infestans, T. pallidipennis, T. phyllosoma, and Rhodnius prolixus) in third and fourth instars were used to evaluate their susceptibility to one T. cruzi strain isolated in Mexico. The susceptibility was determined by: a) percentage of infected triatomines, b) amount of flagellates in bug feces and c) amount of blood ingested. We found that in most species of triatomines tested the third instar was more susceptible than fourth instar. The order of susceptibility to T. cruzi was: T. pallidipennis > T. barberi > T. phyllosoma > T. infestans > R. prolixus.

Animals↗
PubMed1993

Canestriniid mites (Acari, Astigmata, Canestriniidae) occurring on chrysomelidae (Insecta, Coleoptera) in neotropical region. II. Genera Ovarrothiana n. gen., Ennodithiana n. gen.

Two genera Ovarrothiana, Ennodithiana and 10 species are described as new: Ovarrothiana nikodemi from Peru, Brazil, O. erazmi from French Guiana, Brazil, O. ozannae from Peru, Brazil, Ecuador, O. ludomiri and O. leopoldi from Bolivia, Ennodithiana messalinae from Costa Rica, Cuba, E. maniusi from Brazil, Mexico, E. penelopae from Surinam, Brazil, E. medoni and E. megesi from Brazil.

Animals↗
PubMed1996

Association between duration of humid season and geographical distribution patterns of different species of chewing lice (Mallophaga:Insecta) infesting domestic chickens in Nigeria.

In a countrywide study of the geographical distribution patterns of chicken lice in Nigeria, 3 species, Menacanthus pallidulus (Neumann 1912), Goniodes dissimilis Denny, 1842, and Menopon gallinae (Linnaeus, 1758), were completely restricted to within areas with a long humid season (6-12 humid mo per yr). In constrast, 4 species, Cuclotogaster occidentalis Tendeiro, 1954, Menacanthus cornutus (Schommer, 1913), Amyrsidea powelli (Bedford, 1920), and Goniodes gigas (Taschenberg, 1879), thrived only in areas where the humid season was of a short duration (< or = 5 mo). The last 3 named species extended also into the fringes of areas with a long humid season (6-8 humid mo) at significantly reduced numbers. They were entirely absent in areas with a particularly protracted humid season (9-12 humid mo). Three other species. Numidilipeurus tropicalis (Peters, 1931), Goniocotes gallinae (DeGeer, 1778), and Lipeurus caponis (Linnaeus, 1758), were just as abundant in areas of a long humid season as they were in areas with a short humid season. It was concluded that there was an association between duration of the humid season and the geographical distribution patterns of certain species of chicken lice in Nigeria. The duration of the humid season might thus provide a means of predicting the potential occurrence of some species of chicken lice in a particular area.

Analysis of Variance↗
PubMed1998

[The synanthropy of the calliphorids (Insecta, Diptera) of Curitiba, Paraná, Brazil].

The calliphorids synantropics were studied in three different environments--urban, rural and forest area--in metropolitan region of Curitiba, Paraná, Brazil during october and december of 1996 to estimate the abundance, preferences of the adults to baits (fresh fish, bird liver and human faeces) and the synanthropic index for the most abundant species. A total of 3399 calliphorids of 13 different species were sampled: Phaenicia eximia (Wiedemann, 1819), Phaenicia cuprina (Wiedemann, 1818), Phaenicia sericata (Meigen, 1826), Cochliomyia macellaria (Fabricius, 1775), Chrysomya putoria (Wiedemann, 1818), Chrysomya albiceps (Wiedemann, 1819), Chrysomya megacephala (Fabricius, 1794), Hemilucilia segmentaria (Fabricius, 1805), Hemilucilia semidiaphana (Rondani, 1850), Paralucilia xanthogeneiates (Dear, 1850), Paralucilia fulvinota (Bigot, 1877), Sarconesia chlorogaster (Wiedemann, 1930) and Calliphora erytrocephala Meigen, 1826.

Animals↗
PubMed1993

Immunochemical analysis of insect carbohydrate antigenic determinants: recognition of a terminal alpha-linked N-acetylgalactosamine-containing epitope of Calliphora vicina neutral glyco(sphingo)lipids and detection in additional orthopteran and dipteran species.

A cloned mouse hybridoma was established that secreted a monoclonal antibody directed against certain neutral glycosphingolipids of the third-instar larvae of Calliphora vicina (Insecta: Diptera). The isotype of the designated monoclonal antibody CNF-I (Calliphora Neutral Fraction) was determined as IgG3. By the use of purified neutral glycosphingolipids of C. vicina, qualitative thin-layer chromatography immunostaining and semi-quantitative enzyme-linked immunosorbent assay determinations, the epitope was specified as a terminal alpha 1-4-linked N-acetylgalactosamine to subterminal N-acetylgalactosamine, which is present on the components GalNAc alpha 4GalNAc beta 4GlcNAc beta 3Man beta 4Glc beta lCer (N5a) and GalNAc alpha 4GalNAc beta 4-(6' PEtn-)GlcNAc beta 3Man beta 4Glc beta lCer (Nz5a). After enzymatic removal of the terminal alpha-N-acetylgalactosamine residue, the epitope reactivity was destroyed. The distribution of the CNF-I recognized epitope among neutral glycolipids of other insects was shown for: Locusta migratoria (Insecta: Orthoptera); and, Chironomus tentans and Drosophila melanogaster (Insecta: Diptera).

Acetylgalactosamine↗
PubMed2005

Preliminary survey of the mayflies (Ephemeroptera) and caddisflies (Trichoptera) of Big Bend Ranch State Park and Big Bend National Park.

The mayfly (Insecta: Ephemeroptera) and caddisfly (Insecta: Trichoptera) fauna of Big Bend National Park and Big Bend Ranch State Park are reported based upon numerous records. For mayflies, sixteen species representing four families and twelve genera are reported. By comparison, thirty-five species of caddisflies were collected during this study representing seventeen genera and nine families. Although the Rio Grande supports the greatest diversity of mayflies (n=9) and caddisflies (n=14), numerous spring-fed creeks throughout the park also support a wide variety of species. A general lack of data on the distribution and abundance of invertebrates in Big Bend National and State Park is discussed, along with the importance of continuing this type of research.

Animals↗
PubMed1975

[Morphological and functional variations of the muscles of invertebrates].

The problem of muscle evolution among Invertebrates has been considered, mainly in obliquely strated fibers of Annelida and in trasversally striated fibers of Insecta. In both groups the morphological variations run parallel to the functional requirements; similar modulations, in fact, have been observed in fast and slow acting muscle fibers independently from the basic pattern of Insecta and Annelida fibers. Fast acting muscles are characterized by a lesser diameter of myosin filaments and a low thin-to-thick filament ratio. On the contrary, the slow acting muscles show a greater diameter of the myosin filaments and a higher thin-to-thick filament ratio. These observations agree with the hypothesis of a common origin of almost all muscular systems.

Animals↗
PubMed1996

Male-killing bacterium in a fifth ladybird beetle, Coleomegilla maculata (Coleoptera:Coccinellidae).

Inherited symbionts which selectively cause the death of male hosts are found widely across the Insecta. Previous studies have shown a single, but different micro-organism to be responsible for male-killing in each taxonomic group studied. We here produce evidence that within a group of insects, the Coccinellidae, there is more than one causal agent of male lethality. We report a novel observation of a male-killing trait in the species Coleomegilla maculata. Six of 26 crosses were found to produce a female-biased sex ratio associated with a low egg hatch-rate. The trait was matrilinearly inherited and was observed to be tetracycline-sensitive. However, tests which indicate the presence of a Rickettsia, previously found to cause male-killing in another member of the Coccinellidae, Adalia bipunctata, proved negative. We therefore conclude that the phenomenon of male-killing is multicausal, within, as well as between, taxonomic groups of the Insecta.

Animals↗
PubMed1999

Structure, development, and evolution of insect auditory systems.

This paper provides an overview of insect peripheral auditory systems focusing on tympanate ears (pressure detectors) and emphasizing research during the last 15 years. The theme throughout is the evolution of hearing in insects. Ears have appeared independently no fewer than 19 times in the class Insecta and are located on various thoracic and abdominal body segments, on legs, on wings, and on mouth parts. All have fundamentally similar structures-a tympanum backed by a tracheal sac and a tympanal chordotonal organ-though they vary widely in size, ancillary structures, and number of chordotonal sensilla. Novel ears have recently been discovered in praying mantids, two families of beetles, and two families of flies. The tachinid flies are especially notable because they use a previously unknown mechanism for sound localization. Developmental and comparative studies have identified the evolutionary precursors of the tympanal chordotonal organs in several insects; they are uniformly chordotonal proprioceptors. Tympanate species fall into clusters determined by which of the embryologically defined chordotonal organ groups in each body segment served as precursor for the tympanal organ. This suggests that the many appearances of hearing could arise from changes in a small number of developmental modules. The nature of those developmental changes that lead to a functional insect ear is not yet known.

Animals↗
PubMed1975

Structural and functional heterogeneity in an insect muscle.

Singing muscles of the katydid, Neoconocephalus robustus (Insecta, Tettigoniidae) are neurogenic, yet perform at contraction-relaxation frequencies as high as 212 Hz (Josephson and Halverson, '71). The mechanical and electrical responses of different bands of one of these muscles (the dorsal longitudinal muscle, DLM) has been examined with respect to ultrastructural features of each part which may be related to muscle performance. The DLM is composed of three bands and is innervated by four motoneurones. The cell bodies of three of these motoneurones occur ipsilaterally in the prothroracic ganglion; the cell body of the other motoneurone is contralateral in the mesothoracic ganglion. Three of the motoneurones (as yet unidentified fast axons) initiate extraordinarily fast twitches (rise time equal 7.3 msec, half duration equals 14.3 msec, 25 C), the fourth (an unidentified slower axon) evokes twitches which are considerably slower (rise time equals 18.9 msec, half duration equals 5.10 msec). Whereas the ventral and medial bands of the muscle are innervated only by fast axons (some fibers of the medial band are doubly innervated), the dorsal band is innervated by both a fast axon and the slower axon. A few fibers of the dorsal band are doubly innervated. The structure of fibers from the ventral and medial bands is very similar, with short sarcomeres (4.0 and 4.3 mum, respectively) and thin strap-like myofibrils delineated by well-developed sarcoplasmic reticulum (SR). Twenty-four percent of the volume of ventral band fibers is SR and the diffusion distance from SR to the center of the adjacent myofibril averages 0.083 mum. Twenty percent of the medial band fiber volume is SR, with a diffusion distance of 0.118 mum. Ventral and medial band fibers contain about 40% mitochondria, and 33% myofibrils. The dorsal band fibers have longer sarcomeres (9.5 mum), and only 10% of the fiber volume is SR. The muscle fibrils of the dorsal band are larger and consequently the diffusion distance is greater (0.227 mum) than in the ventral and medial bands. Mitochondria comprise 23% of the volume of dorsal band fibers. Most dorsal band mitochondria are aggregated into distinct clumps. Although some dorsal band fibers are innervated by a fast axon and some by the slower axon, the dorsal band fibers are structurally homogeneous, suggesting that neurotrophic effects are not important in maintaining the structure of dorsal band fibers. The mechanical-electrical performance and ultrastructure of the ventral and medial bands suggest their roll as fast, metabolically active but weak muscles, used in singing; the dorsal band as a slower but stronger muscle, perhaps involved in postural movements of the wing during singing.

Animals↗
PubMed2002

Ephemeroptera egg chorion characters: a test of their importance in assessing phylogenetic relationships.

The egg chorion ultrastructures of the Hermanella-Traverella (Insecta: Ephemeroptera) species complex were studied from a comparative point of view and used for the first time in a cladistic analysis. Egg characters, along with other nymphal and adult morphological characters, were used to assess the phylogenetic relationships of the species complex. In order to test the value of egg characters, analyses were performed on three matrices: 1) egg characters alone, 2) adult and nymphal characters, and 3) adult, nymphal, and egg characters. The computer program Pee-Wee was used to carry out the analysis. The cladistic analysis confirmed the value and potential of egg chorionic characters in assessing the phylogenetic relationships among ephemeropteran species. Egg characters, when added to the nymphal and adult character matrix, provided extra support to the monophyletic nature of the Hermanella-Traverella complex. Previously weakly defined clades were also resolved based on the new evidence. In the species studied the egg chorionic structures as well as their shape did not change after oviposition or water immersion, remaining constant through the different maturation stages of each species (mature nymph, subimago, and imago). For this reason, the eggs are a valuable source of information to unambiguously identify and associate a nymph to its correspondent adult stage when rearing is not possible.

Animals↗
PubMed1995

Does a heterogeneous distribution of food or pesticide affect the outcome of toxicity tests with Collembola?

The reproduction of two closely related soil microarthropods, Folsomia candida Willem and Folsomia fimetaria L. (Insecta: Collembola), was tested under the influence of the insecticide dimethoate. Dimethoate had an adverse effect on the survival of adults and their reproduction in concentrations of about the recommended field dose, with F. fimetaria being more sensitive than F. candida. The experimental conditions were altered to evaluate the realism in the basic single species/single chemical reproductive test system. The importance of the spatial distribution of dimethoate was studied with food applied to the surface (original procedure), mixed homogeneously in the whole soil profile or only in the top layer, or mixed heterogeneously into the soil preserving the small granula of the yeast originally in the commercial formulation. Toxicity decreased significantly when exposure could be avoided in an uncontaminated bottom layer and even more if food was available in this soil horizon. But the results indicate that Collembola were not able to completely avoid dimethoate when they had the choice. For extrapolation purposes a simple test system may be sufficient as EC50 was changed less than one order of magnitude with the different test designs. In terms of EC50 the outcome of a toxicity test with a heterogeneous distribution of food and dimethoate was changed only slightly but the effects to suboptimally fed populations should be considered because they may be more vulnerable.

Animals↗