A revision of the genus Aleuas is made, and the genus is redefined. Four known species are redescribed on the basis of the examination of their types and of newly collected specimens. Four new species are described from materials collected by the author or found in the collections of the Academy of Natural Sciences of Philadelphia and the Museu Nacional of Rio de Janeiro. All species of the genus live in the southern part of S. America, east of the Andes. The genus Zygoclistron is closely related, and together with Aleuas, these genera constitute the tribe Aleuasini of the Acrididae Copiocerinae. The position of the Aleuasini within the Copiocerinae has been recently contested on the basis of certain anatomical and cytological evidence.

Some observations on the mating behavior of the Mediterranean ground mantis Ameles decolor are reported. Sexual cannibalism occurred between female and male; cannibalism occurred between adult males and between adult females. A courtship behavior of the male before mating is described for the first time. Comparisons with other taxa and explanations of courtship occurrence are given.

A junior homonym was detected among phasmid genera and the following replacement name is proposed: Redtenbacherus nom. nov. for Ernodes Redtenbacher, 1908. New combinations are proposed for the species group names currently included in this genus. Redtenbacherus antennatus (Redtenbacher, 1908) comb. nov.; Redtenbacherus jacobsoni (Rehn, 1912) comb. nov. and Redtenbacherus sumatranus (Redtenbacher, 1908) comb. nov.

A new species of Usambilla Sjöstedt, 1909, is described from the highlands of northwestern Tanzania. U. hanangensis Hemp n. sp. occurs in the montane zone on Mt. Hanang and on montane grasslands of the Mbulu District. Notes on habitat and co-occurring Saltatoria species are given. The known species of Usambilla are compiled with information on their ecology and biogeography.

We used mitochondrial (12s, 16s) and nuclear (18s, 28s) ribosomal gene sequences to derive a phylogeny of the Eumastacoidea, with the aims of a) clarifying the position of the Proscopiidae with respect to the Eumastacoidea b) testing the phylogenetic hypothesis and classification advanced by Descamps 1973b for the Eumastacoidea, and c) deriving a time scale for the phylogeny based on molecular clock calculations. Four different analysis methods were employed: maximum parsimony, neighborjoining assuming minimum evolution, maximum likelihood and Bayesian analysis. The genes were analysed separately and after concatenation. The sample included 6 of the 7 families and 12 of the 31 subfamilies of the Eumastacoidea, and three proscopiids. We included tetrigoids (as outgroup) and tanaoceroids and trigonopterygoids to provide polarity.

No analysis supported placing the Proscopiidae within any of the existing branches of the Eumastacoidea. Some placed the two taxa as sistergroups within a Eumastacoidea s. lat., and some indicated that they are separate superfamilies. We cannot distinguish between these two possibilities with the present data.

Within the Eumastacoidea s.str. all of the groupings of subfamilies (i.e., families) proposed by Descamps were well-supported. Higher nodes of the phylogeny were in general only weakly supported. Descamps' suprafamilial groupings appeared in some but not all analyses. Of these groupings, the Cryptophalli (=Chorotypidae plus Episactidae) were not well supported, the Stenophalli (Eumastacidae plus Morabidae) were reasonably well supported, while the Disclerophalli (=Thericleidae plus Euschmidtiidae) were strongly supported, and additionally the Gomphomastacinae were associated with it. (The Euphalli, containing only the Indian family Mastacideidae, were not included in the analysis.)

The sequence data did not allow the assumption of a molecular clock, and for this reason the nodes of the phylogeny could not be dated.

Nicarchus enyalius Rehn (Ommatolampini: Vilernae) is synonomized with N. erinaceus Stål, leaving the genus monospecific. A redescription is given.

The previously unknown male of Cryptacris costaricensis Descamps & Rowell is described, and the genus redescribed; its probable position within the Vilernae is reaffirmed, and it is newly recorded from Panama as well as from Costa Rica.

A new species of Pauracris Descamps & Amedegnato, a genus previously known only from Colombia, is described from Caribbean Costa Rica (P. brachyptera). Christenacris Descamps and Rowell is provisionally transferred from the Ommatolampini to the Pauracrini.

A new subspecies of Ateliacris annulicornis (Bruner) (A. a. pulchra) (Syntomacrini: Caloscirtae) is described from Western Costa Rica. It differs from the nominate form principally in the coloration of the male.

The systematic position of Leptalacris Descamps & Rowell is reconsidered, and it is transferred from the Ommatolampinae: Clematodinini to the Eucopiocerae group.

One new species (jagoi) and one new subspecies (chrysonota salazari) of Rhachicreagra are described from Costa Rica (Abracrini). Additional notes on Rh. gracilis Bruner, drymocnemensis Jago & Rowell and dierythra Rowell are given.

Orthopteran community composition varies with habitat quality. The distribution of Orthoptera species depends primarily on which vegetation type provides food resources and habitat. For insight into this relation between distribution and habitat quality we studied the 21 most-abundant orthopteran species in El Cimatario National Park (State of Querétaro, México) in four vegetation types. We found that nearly half of these species tended to inhabit a particular vegetation type. This study is a first contribution exploring the relation between vegetation and distribution of Mexican Orthoptera.

The insecticide diflubenzuron (DFB), a benzoylphenyl urea, decreases fecundity in insects by a still unknown mechanism. The objective of this study was firstly to see the effects of DFB on female reproduction, after its ingestion by Schistocerca gregaria females five days following imaginal molt. DFB significantly delayed the timing of the first and of the second laying when compared to control females. DFB-treated females laid eggs only twice, while control females had, as typical, up to five ovipositions. DFB action on ovarian development and hemolymphatic ecdysteroid levels were also evaluated in females. Ecdysteroid titres in control females fluctuated according to the ovarian cycle, reaching a peak of around 170 pmol/mL hemolymph during the vitellogenic phase. In DFB-treated females, hemolymph ecdysteroid titres remained very low and oocyte growth was reduced. The treatment caused early oocyte resorption and any eggs deposited never hatched.

Surfaces of the eggs of acridids show chorionic sculpturing — distinct features that can be used to identify species. With a scanning electron microscope, we document dimensions and surface detail for eggs of two common Indian acridids: Hieroglyphus banian and Acrida exaltata. Their eggs are characterized by distinguishing features: A. exaltata by many small tubercles scattered almost uniformly, H. banian by thick-ridged hexagonal polygons. The similarities and dissimilarities of their egg-surfaces to those of other acridid species are not consistent with subfamilial classification.

Chortophaga australior Rehn and Hebard (Orthoptera: Acrididae) is considered a species distinct from Chortophaga viridifasciata (DeGeer). Collections across Nebraska have shown that the characters used to separate these two species are inconsistent and that the average state of these characters appears to be related to the time of the season during which the adults are collected. Until further study clarifies the status of C. australior, we suggest that its specific status be considered questionable.

Nutritional ecology of the Central American locust Schistocerca piceifrons piceifrons was studied using specimens from Socorro Island, Mexico. They were fed in the laboratory with common plants obtained from the island: Ficus cotinifolia (Moraceae), Cordia curassavica (Boraginaceae), Nicotiana stocktonii (Solanaceae), and Psidium sartorianum (Myrtaceae). We measured nutritional and growth rates in dry weights: intake, gain in weight, as well as some Waldbauer indices equivalents: efficiency of conversion of ingested food (ECI), efficiency of conversion of digested (absorbed) food (ECD), and approximate digestibility (AD). We compared nutritional indices equivalents between female and male, between gregarious and solitary phases and between diets, employing ANCOVAs. We found no differences in metabolic efficiencies between female and male locusts, no differences between gregarious and solitary locusts. We found that F. cotinifolia is a food plant that favors the intake, nutritional efficiencies and steady growth of the Central American locust, in comparison to other food plants.

A modified Petraborg index is proposed to correct an underestimation error in the original formula and its use illustrated in censusing singers of Oecanthus niveus in Mexico. The unmodified index departs widely from observed densities; the modified index does not.