@article {57665, title = {Mechanical filtering for narrow-band hearing in the weta}, year = {2011}, abstract = {

This paper constitutes a major attempt to associate tympanic deflections with the mechanoreceptor organ location in an acoustic insect. The New Zealand tree weta (Hemideina thoracica) has tympanal ears located on each of the prothoracic tibiae. The tympana exhibit a sclerotized oval plate, membranous processes bulging out from the tibial cuticle and many loosely suspended ripples. We used microscanning laser Doppler vibrometry to determine how such a tympanal membrane vibrates in response to sound and whether the sclerotized region plays a role in hearing. The tympanum displays a single resonance at the calling frequency of the male, an unusual example of an insect tympana acting as a narrow bandpass filter. Both tympana resonate in phase with the stimulus and with each other. Histological sections show that the tympanal area is divided into two distinct regions, as in other ensiferans. An oval plate lies in the middle of a thickened region and is surrounded by a transparent and uniformly thin region. It is hinged dorsally to the tympanal rim and thus resembles the model of a \‘hinged flap\’. The thickened region appears to act as a damping mass on the oscillation of the thin region, and vibration displacement is reduced in this area. The thinner area vibrates with higher amplitude, inducing mechanical pressure on the dorsal area adjacent to the crista acustica. We present a new model showing how the thickened region might confer a mechanical gain onto the activation of the crista acustica sensory neurons during the sound-induced oscillations.

}, keywords = {ensiferan ear, laser vibrometry, mechanical tuning, tympanum vibration, weta}, doi = {10.1242/jeb.050187}, url = {http://jeb.biologists.org/cgi/doi/10.1242/jeb.050187https://syndication.highwire.org/content/doi/10.1242/jeb.050187}, author = {Lomas, K. and Montealegre-Z, F. and Parsons, S. and Field, L. H. and Daniel Robert} } @article {53306, title = {Substrate-Borne Vibration Mediates Intrasexual Agonism in the New Zealand Cook Strait Giant Weta (Deinacrida rugosa)}, journal = {Journal of Insect Behavior}, year = {2018}, month = {Dec-11-2018}, abstract = {

Substrate-borne vibrational communication is a common mode of information transfer in many invertebrate groups, with vibration serving as both primary and secondary signal channels in Orthopterans. The Cook Strait giant weta, Deinacrida rugosa (Orthoptera: Anostostomatidae), is an endangered New Zealand insect whose communication system has not been previously described. After field observations of intraspecific interactions in D. rugosa provided preliminary evidence for substrate-borne vibrational communication in the species, we sought to identify the following: vibrational signal structure, the mechanism of signal production, whether signal production is a sexually dimorphic trait, whether substrate-borne signals encode information regarding sender size, the primary social context in which vibration is utilized and finally, the function of vibrational signaling in the species. We used laser Doppler vibrometry to show that D. rugosa males produce low frequency (DF\ =\ 37.00\ \±\ 1.63 Hz) substrate-borne vibrations through dorso-ventral tremulation. Rarely produced by females, male signals appear to target rivals while both are in the direct physical presence of a female. Tremulatory responses to playbacks were only produced by males in male-male-female trial contexts, and neither sex exhibited walking vibrotaxis to playback signals, indicating that substrate-borne vibrational signals are not likely a component of the courtship repertoire. While we found that vibrational signal structure was not closely related to signaler size, males that initiated male-male signaling bouts held a significant advantage in contests.

}, keywords = {Agonism, Deinacrida rugosa, giant weta, seismic signals, substrate-borne signals, vibrational communication}, issn = {0892-7553}, doi = {10.1007/s10905-018-9700-2}, url = {http://link.springer.com/10.1007/s10905-018-9700-2}, author = {Howard, Daniel R. and Schmidt, Ashley P. and Hall, Carrie L. and Mason, Andrew C.} } @article {48122, title = {Tackling an intractable problem: Can greater taxon sampling help resolve~relationships within the Stenopelmatoidea (Orthoptera: Ensifera)?}, journal = {Zootaxa}, volume = {4291}, year = {2017}, month = {Nov-07-2017}, pages = {1}, abstract = {

The relationships among and within the families that comprise the orthopteran superfamily Stenopelmatoidea (suborder Ensifera) remain poorly understood. We developed a phylogenetic hypothesis based on Bayesian analysis of two nuclear ribosomal and one mitochondrial gene for 118 individuals (84 de novo and 34 from GenBank). These included Gryllacrididae from North, Central, and South America, South Africa and Madagascar, Australia and Papua New Guinea; Stenopelmatidae from North and Central America and South Africa; Anostostomatidae from North and Central America, Papua New Guinea, New Zealand, Australia, and South Africa; members of the Australian endemic Cooloola (three species); and a representative of Lezina from the Middle East. We also included representatives of all other major ensiferan families: Prophalangopsidae, Rhaphidophoridae, Schizodactylidae, Tettigoniidae, Gryllidae, Gryllotalpidae and Myrmecophilidae and representatives of the suborder Caelifera as outgroups. Bayesian analyses of concatenated sequence data supported a clade of Stenopelmatoidea inclusive of all analyzed members of Gryllacrididae, Stenopelmatidae, Anostostomatidae, Lezina and Cooloola. We found Gryllacrididae worldwide to be monophyletic, while we did not recover a monophyletic Stenopelmatidae nor Anostostomatidae. Australian Cooloola clustered in a clade composed of Australian, New Zealand, and some (but not all) North American Anostostomatidae. Lezina was included in a clade of New World Anostostomatidae. Finally, we compiled and compared karyotypes and sound production characteristics for each supported group. Chromosome number, centromere position, drumming, and stridulation differed among some groups, but also show variation within groups. This preliminary trait information may contribute toward future studies of trait evolution. Despite greater taxon sampling within Stenopelmatoidea than previous efforts, some relationships among the families examined continue to remain elusive.

}, keywords = {Anostostomatidae, Cooloola, drumming, genetic, Gryllacrididae, karyotype, Lezina, Orthoptera, sound production, Stenopelmatidae}, issn = {1175-5326}, doi = {10.11646/zootaxa.4291.110.11646/zootaxa.4291.1.1}, url = {https://biotaxa.org/Zootaxa/issue/view/zootaxa.4291.1https://biotaxa.org/Zootaxa/article/view/zootaxa.4291.1.1}, author = {Amy G. Vandergast and David B. Weissman and Dustin A. Wood and D. C. F. Rentz and Corinna S. Bazelet and Norihiro Ueshima} } @article {40445, title = {Reproductive Behavior of Ground Weta (Orthoptera: Anostostomatidae): Drumming Behavior, Nuptial Feeding, Post-copulatory Guarding and Maternal Care}, journal = {Journal of the Kansas Entomological Society}, volume = {77}, year = {2004}, pages = {414-428}, chapter = {414}, abstract = {

Compared to other ensiferan Orthoptera such as true crickets (Gryllidae) and katydids (Tettigoniidae) relatively little is known about the reproductive behavior of Anostostomatidae (formerly Stenopelmatidae), the king crickets, weta and allies. Moreover, although the New Zealand species (the weta) are best known, there is little knowledge of the biology of ground weta (Hemiandrus species), a variable genus especially with regard to ovipositor length. This paper presents observations of mating and post-mating behavior of several Hemiandrus species with short ovipositors. Sexually active males and females drum their abdomens on the substrate, apparently as local signals for mate attraction (pheromones may be involved in long distance communication). After mating there is both maternal and paternal investment. Females provide care to eggs and young larvae and males provide a spermatophylax to the female, a mating meal that, in other ensiferan Orthoptera can be an important source of nutrition. In contrast to other ensiferans, however, the spermatophylax of Hemiandrus species with short ovipositors is deposited on the female\’s abdomen, a separate location from the sperm ampulla. The spermatophylax is deposited while the male is attached to the female\’s underside, apparently to her modified 6th abdominal sternite. Also, in contrast to related taxa, males remain with their mates while the mating meal is eaten. These observations indicate that ground weta are excellent systems for examining behavioral and ecological questions about the evolution of complex signals, as well as the evolution of maternal and paternal investment.

}, keywords = {communication, Hemiandrus, mating behavior, parental investment}, url = {http://www.jstor.org/stable/25086232 }, author = {Darryl T. Gwynne} } @inbook {40322, title = {Communication and Reproductive Behaviour in North American Jerusalem Crickets (Stenopelmatus) (Orthoptera: Stenopelmatidae)}, booktitle = {The Biology of Wetas, King Crickets and their Allies}, year = {2001}, pages = {351-375}, publisher = {CABI}, organization = {CABI}, chapter = {19}, address = {Wallingford, United Kingdom}, issn = {0851994083}, author = {David B. Weissman} }