Registered users receive a variety of benefits including the ability to customize email alerts, create favorite journals list, and save searches.
Please note that a BioOne web account does not automatically grant access to full-text content. An institutional or society member subscription is required to view non-Open Access content.
Contact helpdesk@bioone.org with any questions.
An important but under studied component of grasshopper ecology is how pathogens affect grasshopper population dynamics. However, insect population responses to disease may depend upon age demographics which vary temporally. In a field experiment, we varied grasshopper [Camnula pellucida (Scudder)] developmental stage (3rd instar, 4th instar, 5th instar, and adults) and fungal pathogen exposure (lab and field) and measured grasshopper mortality and survival. Lab exposed grasshoppers were directly inoculated with the pathogen, while field exposed grasshoppers were passively exposed to naturally occurring spores. Disease increased grasshopper mortality rates and decreased overall survival. However, this effect varied with grasshopper developmental stage and mode of pathogen exposure. Adults were far less susceptible to fungal infection than nymphs. Disease mortality was 52% higher in lab exposed grasshoppers compared to individuals exposed to a natural fungal epizootic in the field. Lab exposure decreased 3rd instar survival rates more than exposure to the pathogen in the field. In contrast, grasshopper survival was invariant with disease exposure for 4th and 5th instars due to peak levels of naturally occurring fungal spores. By August 2010, the field epizootic was declining and food availability became the most important determinant of adult grasshopper survival. Therefore, age demographics may need to be considered when predicting how grasshopper populations will respond to disease.
Multiple paternity within clutches has been recorded among a variety of organisms. The degree of genetic similarity between parents may influence the number and viability of offspring. Females may therefore mate with several males as an insurance against sterile, low quality or genetically incompatible mates, but also to obtain half sibling offspring that are genetically and phenotypically more diverse. We examine the links between polyandry, multiple paternity and offspring phenotypic diversity in the color polymorphic pygmy grasshopper Tetrix subulata. By experimentally mating virgin females and genotyping the resulting offspring using microsatellite markers, we demonstrate that polyandrous females can produce offspring sired by different males. Analyses of microsatellite data and color patterns of captive reared families produced by wild caught females that were not mated in the laboratory, confirmed that multiple paternity occurs in the wild, and that it may increase color morph diversity among half-siblings. Polyandrous mating behavior may thus influence the evolutionary dynamics and maintenance of color polymorphism in this species.
This article describes and names a new species of Oecanthus Serville, 1831 from the western United States. Oecanthus texensis n. sp. Symes & Collins is currently known from southern Oklahoma, Texas, southern Arizona, and southwestern Idaho. Habitats include desert, prairie, weedy fields, and woody secondary growth. O. texensis has been collected in oak, walnut, pinyon pine, and mesquite, as well as a variety of landscaping hedges and shrubs. The Oecanthus genus contains four clusters of species. The tegmina shape, song structure, and antennal markings suggest that O. texensis falls within the varicornis group. The structure of the call is similar to the other members of the varicornis species group, but the pulse rate is unique. Song analysis shows that at 25 °C, O. texensis produces a continuous trill with approximately 41 pulses per second and a dominant frequency of 3.8 kHz, making it the slowest pulsing member of the varicornis group.
There are few suitable monitoring tools for assessing the effectiveness of management for threatened insect taxa. This is especially true for cryptic arboreal species of nocturnal flightless orthopterans in the genus Deinacrida from New Zealand. Systematic searching of habitat during the day was compared with footprint tracking tunnels baited with peanut butter as methods for monitoring the arboreal giant weta Deinacrida heteracantha and Deinacrida mahoenui (Orthoptera: Anostostomatidae). Searching by day required more time (3h per transect) than operating tracking tunnels (1.4h). Lines of 30–35 tracking tunnels spaced 30 m apart could be quickly set to sample large areas. Searching may provide additional information including the species, age class, and sex, whereas tracking tunnels yield presence/absence data for giant weta that were larger than other anostostomatid present. Both methods provide indices of relative abundance: it is impractical in tall forest to accurately estimate absolute density whereas tracking tunnel results are related to the activity of weta. Weta activity may depend on vapour pressure deficit modulated by the temperature. For conservation and monitoring purposes, we recommend that tracking tunnels be used first to detect giant weta and only then search for them if further data is required.
In this paper seven new species are described: Machimoides sofiaen. sp., from the Colombian Andes, Lichenodraculus holgerin. sp., from the Guiana Shield and Venezuelan Amazon, Markia nicolasin. sp., from Costa Rica, M. agudeloin. sp., from Guyana (previously British Guiana) near the border with Suriname, M. bolivarensisn. sp., from the states of Bolívar and Amazonas in Venezuela (located on the Guiana Shield), M. guerreroin. sp., and M. gaianiin. sp., from the Venezuelan Andes. A female of Apolinaria hygracantha (Karsch, 1896) is described and illustrated. Keys to species of all genera treated here are provided. The distribution of the genera Markia and Machimoides is discussed; for the latter genus discussion focuses on the current status of its species. Description of new species treated herein expands considerably the distribution range of the genera studied, also the generic diagnostic characters are enriched and reinforced.
Forty-four species of Phaneropterinae are recorded from Dzanga-Ndoki National Park in the Central African Republic. Eight species collected within the park are described as new to science: Phlaurocentrum morettoi n. sp., P. paratuberosum n. sp., P. elegans n. sp., Myllocentrum raggei n. sp., Poreuomena sanghensis n. sp., Cestromoecha longicerca n. sp., C. magnicerca n. sp., and Goetia purpurea n. sp. An additional new species from Guinea is described from specimens preserved in the Museo Nacional de Ciencias Naturales of Madrid, Poreuomena huxleyi n. sp. Eurycorypha stylata Stål, 1873 is recorded for the first time from Burkina Faso and Brycoptera lobataRagge, 1981 from Ivory Coast. The following synonyms are established: Enochletica affinis Bolívar, 1906 is synonymized with Enochletica ostentatrixKarsch, 1896, Poreuomena gladiator Bolívar, 1906 is synonymized with Poreuomena forcipata Sjöstedt, 1902, and Azamia doriae (Griffini, 1906) is synonymized with Azamia biplagiataBolívar, 1906. In addition, morphological characters of previously unknown females of Phaneroptera maculosaRagge, 1956 and Eurycorypha canaliculataKarsch, 1890, and males of Myllocentrum stigmosum (Karsch, 1896) and Cestromoecha crassipes (Karsch, 1890) are described. The presence of titillators in four African genera (Gelotopoia, Brycoptera, Phlaurocentrum and Azamia) is recorded for the first time. In the genus Zeuneria, a sub-equally bilobed, dorsally curved, dorso-lateral abdominal appendage is described for the first time. This new structure apparently delimits an abdominal gland of unknown function on the second tergite.
This article is only available to subscribers. It is not available for individual sale.
Access to the requested content is limited to institutions that have
purchased or subscribe to this BioOne eBook Collection. You are receiving
this notice because your organization may not have this eBook access.*
*Shibboleth/Open Athens users-please
sign in
to access your institution's subscriptions.
Additional information about institution subscriptions can be foundhere