Males of most species of crickets and katydids produce species-specific calling songs to attract conspecific females. The typical stridulatory apparatus of the Ensifera consists of a file-and-scraper system in the basal dorsal region of the forewings (tegmina): the file on the underside of the cubital vein of one tegmen is composed of a series of lamelliform teeth and is run against the sclerotized scraper at the edge of the other tegmen. The region directly distal of the cubital vein is often thin and glassy and serves to amplify and spread the sound. In stridulating crickets the tegmina are quite symmetrical with both the left and the right one containing a file, which is considered the ancestral condition (Béthoux 2012). Most of these crickets adopted a right-over-left wing overlap and use only the right file. The few extant species of the ancient group Hagloidea have bilaterally symmetrical tegmina, both with functional files, and individual males can change the overlap (Morris & Gwynne 1978). Katydids are distinguished by a left-over-right wing overlap, with a stridulatory file on the underside of the left tegmen, and a scraper on the right one, which usually is also equipped with a mirror as resonating structure.

The main purpose of this paper is the description of two very tiny, long-legged, and short-winged katydids from the eastern slope of the eastern Andean cordillera of south-east Ecuador, Nanoleptopoda nigrifrons gen. et sp. nov. and N. albifrons sp. nov., the first species along with its ultrasound calling song. The monospecific and closely-related genus Parangara is included in Odonturini. Dichopetala inca and Anisophya equatorialis are transferred under the so far monospecific genus Cohnia, so that now the tribe includes three genera with six species from the tropical Andes. The ecological background of wing reduction in relation to elevation is briefly discussed.

Eight katydid species of the leaf-mimicking specialist genus Typophyllum were found in the southeast of Ecuador in an area comprising part of the eastern Andean cordillera and foothills toward the Cordillera del Cóndor in elevations between 850 and 3000 m. They are described along with the peculiar calling songs and other interesting aspects of their biology. Three of these species are new: T. morrisi sp. nov., T. onkiosternum sp. nov. and T. vignoni sp. nov. A fourth species represented by a single male is possibly new as well. In males and females of a species considered as identical with T. egregium Hebard 1924, which was previously known from a unique female specimen, was found a remarkable variation of coloration, in addition to the striking sexual dimorphism typical for the genus, with the females being twice as large as the small males. The latter is related to the curious mating behaviour, which is documented for this species and T. erosifolium Walker 1870. The two other species found in the region are T. bolivari Vignon 1925 and T. mortuifolium Walker 1870. The calling songs of four species were recorded. In T. erosifolium and T. morrisi sp. nov. the sounds are almost pure sine waves at the lower boundary of ultrasound. In T. egregium and T. onkiosternum sp. nov. the spectrum of the carrier frequency is broader, which might be related to lower and denser vegetation at higher elevation. Based on the intraspecific variety found in T. egregium and T. erosifolium, which includes variation in tegmina shape and venation pattern, are established several syonymies among Typophyllum species from western South America. T. erosifolium is found to be identical with T. peruvianum Pictet 1888 syn. nov. Additionally are considered identical T. inflatum Vignon 1925 and T. gibbosusm Vignon 1925 syn. nov., T. trigonum Vignon 1925 and T. quadriincisum Vignon 1925 syn. nov., and finally T. lacinipenne Enderlein 1917 and T. acutum Vignon 1925 syn. nov. and T. undulatum Caudell 1918 syn. nov. The discussion treats the problematic taxonomy of the little walking leaves, bioacoustics, the pre-copulatory riding behaviour, the sophisticated mimesis, and very briefly the uncertain position within the katydid phylogeny.

Rubbed wings, analysed calls and peculiar sound generator structure in males of a conocephaline katydid, Xiphelimum amplipennis, give insight into the making of broadband spectra. High shear forces are indicated by a robust forewing morphology. Intensity is high for frequencies in a 20-60 kHz ultrasonic band. Besides a typical katydid sound-radiating mirror and harp, this insect has a long costal series of semitransparent specular sound radiators. These wing cells are loaded behind by an enlarged and partitioned subwing air space.Calls repeat steadily with five different time-domain sound elements. Distinctive spectra are associated with two of these, giving stepwise frequency modulation that combines to create the exceptionally wide spectral breadth. Broadcast sound levels at 10 cm dorsal, right and left, are near 100 dB. Costal wing-cell sound radiation was explored by loading the costal 'speculae' with wax. This produced almost no decrease in lateral sound levels, but did alter spectral content. Apparently this insect's costal region both baffles and radiates. The species lives at high densities in cluttered vegetation and sound signal attenuation should code via spectral shape for distance ranging.

At the time of writing this little paper, the genus Isophya contains 90 valid species and 11 subspecies, according to Orthoptera Species File Online (Eades & Otte), subsequently abbreviated OSF. The distribution of these brachypterous katydids comprises Europe and western Asia, with most species occurring in the eastern Mediterranean. Only six of the species are from South America. In a revision of the genus Ramme (1951) excluded the neotropical species, which he considered to belong to a particular genus (footnote p. 136). In 1960, encouraged by Uvarov, Karabag already had transferred two Isophya species from Paraguay to his new genus Anisophya: A. hamata and, although not explicitly, A. borellii (both Giglio-Tos 1894). He was unable to study the types of any neotropical “Isophya” species, and based the diagnosis on a male and a female in the Natural History Museum, London, that have been identified by “some unknown authority” as I. hamata. He mentioned also 3 females identified as I. borellii, as well as 2 males and 1 female from Brazil that were not identified to species level. In the introduction to a recent revision of Isophya species from Turkey, Űnal (2003) wrote that the generic affinity of the neotropical species needed confirmation. After identifying a very recently collected female of “I. brasiliensis”, which shares all diagnostic features Karabag listed for his genus Anisophya, I decided to finally move the remaining six neotropical “Isophya” species to that genus.