The uhleri group of the genus Amblycorypha consists of A. uhleri Stål and 4 new species: arenicola, cajuni, longinicta, and rivograndis. The species are easily distinguished in the field by features of their songs, and most specimens can be identified by size and features of the ovipositor and male stridulatory apparatus. Males of the uhleri group produce the most complex calls known for ensiferan Orthoptera and thus earn the common name of “virtuoso katydids”. Each species uses 4 types of wing-movement cycles to produce 4 types of syllable sequences. During these sequences there are gradual and sudden changes in intensity. The 4 types of sequences are produced in more or less predictable order, with a complete song requiring 4 to > 60 s depending on the species, the population, and the temperature. In response to these songs, sexually responsive females make nondescript answering “ticks” immediately before and during the place in the songs where the males produce “type IV” syllables. Available evidence suggests that sequences of type I and II syllables are of special significance in eliciting ticks from females, that type III sequences may function in causing females to approach the male from afar, and that type IV sequences may lessen the chances of cuckoldry by eavesdropping males.

The evolutionary relationships of the New Zealand representatives of the family Anostostomatidae were examined using DNA sequence data. All species of giant weta (Deinacrida), tree weta (Hemideina) and tusked weta (Anisoura, Motuweta) were included in the study plus 4 taxa from the large genus of New Zealand ground weta (Hemiandrus). Sequence data from 2 mitochondrial genes (COI and 12S) were analysed to obtain a hypothesis of the evolution of these species. The 3 New Zealand tusked weta species formed a monophyletic clade with respect to the ground weta and to the giant and tree weta clad0e. We found no support for the placement of Anisoura nicobarica Ander within Deinacridinae as has previously been suggested. The giant and tree weta (Deinacridinae) consistently formed a monophyletic clade with respect to the tusked and ground weta. However, we found little support in our data for the reciprocal monophyly of the tree and giant weta genera. The tree weta Hemideina broughi (Buller) appears to be more closely related to Deinacrida pluvialis Gibbs and D. talpa Gibbs than to any other Hemideina species. The deinacridine radiation of leaf-eating weta comprises at least 6 comparatively ancient lineages (Hemideina and Deinacrida). Habitat-specialisation in South Island appears to have evolved in response to habitat diversification associated with Pliocene mountain building.

The aim of this study was to establish whether feeding preferences exist in Chorthippus parallelus among 4 grass species: Cynosurus cristatus, Dactylis glomerata, Festuca rubra and Lolium perenne. Ten grass microswards, each composed of equal areas of the 4 grass species, were established in early 2003. These were placed in insect cages in early June and the number of feeding signs monitored over a 2-week period, for early instar nymphs (1–2), late instar nymphs (3–4), early adults and late adults. Dactylis glomerata and Lolium perenne were the preferred food choices of late instar nymphs, early adults and late adults, perhaps because of these foods' superior nutritive value and palatability. Festuca rubra was less favored by C. parallelus at all stages of insect maturity, perhaps due to leaf hardness making it difficult for the mandibles to penetrate. An aphid infestation of C. cristatus during early July caused the leaves to senesce and resulted in reduced feeding on this species by early and late adults.

Understanding the relationships between intraspecific diversity and habitat has been greatly enhanced with the advent of molecular markers. Such understanding may help to elucidate complex microevolutionary processes. Melanoplus alpinus, a montane/alpine grasshopper species found in the central and northern Rocky Mountains, has a disjunct distribution with highly divergent mtDNA lineages, structured among meadows and drainages within mountain ranges. Previous analyses showed that genetic differentiation is not distance driven, so habitat factors may account for genetic structuring and diversity within the species. In this study, 3 mtDNA lineages were analyzed for their association with ecological variables, and PCR-RFLP haplotype genetic diversities were analyzed for relationships with elevation, elevation-latitude index, and meadow size. Chi-square analysis revealed mtDNA lineage predominance in particular soil textures, indicating the potential of soil to function as a limiting environmental factor in the distribution of lineages within this species. Genotype-habitat associations did not extend beyond soil, however. No significant relationships existed between genetic diversity within meadows and elevation, elevation-latitude index, or meadow size.

Acoustic signals used during the pair-forming behavior of Isophya modesta modesta are described for the first time. Specimens from Hungary, Rumania and the Ukraine have been studied. The male calling song of I. m. modesta is composed of single syllables. Each syllable consists of a shorter main impulse-series (120 to 240 ms) and a longer terminal impulse-series (200 to 2500 ms), separated from each other by a silent interval of 4 to 9 s. Uniquely in I. m. modesta, females can produce 2 response songs during 1 syllable of the male: after the male's main impulse-series, and most frequently, after the terminal impulse-series. Playback experiments revealed that the second female response song is related to the end of the male's terminal impulse-series. I. m. modesta and I. m. rossica were formerly regarded as two different species only subtle morphological differences being known between the 2 taxa. But as the male calling songs are apparently identical, and with the present state of our knowledge, it is reasonable to treat “I. rossica” as a subspecies of I. modesta. The only remarkable difference in the pair-forming acoustic communication of the 2 subspecies is the different timing of female response song, indicating that the 2 taxa have diverged from each other to a certain degree.

Description of a new subspecies of Poecilimon mytilenensis Werner 1932. Both the new and the nominate subspecies occur on the island of Lesbos, Greece. Both subspecies differ mainly in the length of the tip of male subgenital plate. In addition to morphological data and a detailed distribution map, descriptions and oscillograms of male song of both subspecies, female song of the nominate subspecies and some data on the unusual mating behavior (ampulla mass 15 % of male body mass) are provided.

Crickets are known to be inefficient sound producers. When calling, typically less than 1% of their metabolic energy is converted into sound. This low efficiency has been attributed to losses within the insect and to poor acoustic coupling with the environment. A previously uninvestigated factor that might contribute to low efficiency is ultrasonic radiation. If the impacts of the plectrum and file teeth excite vibration in the ultrasonic range, then the sound pressure level meters typically used to measure acoustic power would not accurately detect it. We made audible and ultrasound recordings of the calling songs of a phylogenetically diverse group of 6 cricket species, and, for comparison, 2 katydid species. In most of the cricket species, energy was present well into the ultrasonic region as a series of harmonics of the carrier frequency. However, the energy in these peaks was very small in comparison to the audible-range harmonics. There was no evidence of significant oscillations that were not harmonics of the carrier frequency. In all but one cricket species, over 97% of the total audible and ultrasonic energy was contained in the carrier frequency band.

A better understanding of the relative effects that nymphal and adult resource availabilities have on reproductive allocation is needed, given the potentially important implications for the prediction of grasshopper population dynamics. I conducted a field experiment to examine the importance of nymphal and adult resource availabilities on reproductive allocation in the grasshopper Melanoplus sanguinipes (Fabricius). Female nymphs were reared on either high or low nymphal resource availability, with watered and ambient-level adult resource treatments. Adult resource treatments were initiated below the carrying capacity, to allow an examination of food limitation effects on reproductive allocation, while minimizing strong density dependent effects. Although nymphs reared with ad libitum resources had higher adult body mass, nymphal resource availability did not affect reproductive allocation or adult survival. Female M. sanguinipes grasshoppers responded to the increased host plant availability in the watered treatment, by increasing reproduction allocation over the course of the experiment. M. sanguinipes females did not reduce vitellogenesis in response to decreased adult resource availability, but completed development of a lower percentage of ovarioles that initiated development. Although resource dynamics in semi-arid grasslands can change rapidly during grasshopper development, there were no direct effects of limited resource availability for developing nymphs that subsequently affected per capita reproduction of adults.