Systematics of spiny predatory katydids (Tettigoniidae: Listroscelidinae) from the Brazilian Atlantic Forest based on morphology and molecular data

Wing mechanics and acoustic communication of a new genus of sylvan katydid (Orthoptera: Tettigoniidae: Pseudophyllinae) from the Central Cordillera cloud forest of Colombia

Stridulation is used by male katydids to produce sound via the rubbing together of their specialised forewings, either by sustained or interrupted sweeps of the file producing different tones and call structures. There are many species of Orthoptera that remain undescribed and their acoustic signals are unknown. This study aims to measure and quantify the mechanics of wing vibration, sound production and acoustic properties of the hearing system in a new genus of Pseudophyllinae with taxonomic descriptions of two new species. The calling behaviour and wing mechanics of males were measured using micro-scanning laser Doppler vibrometry, microscopy, and ultrasound sensitive equipment. The resonant properties of the acoustic pinnae of the ears were obtained via μ-CT scanning and 3D printed experimentation, and numerical modelling was used to validate the results. Analysis of sound recordings and wing vibrations revealed that the stridulatory areas of the right tegmen exhibit relatively narrow frequency responses and produce narrowband calls between 12 and 20 kHz. As in most Pseudophyllinae, only the right mirror is activated for sound production. The acoustic pinnae of all species were found to provide a broadband increased acoustic gain from ~40-120 kHz by up to 25 dB, peaking at almost 90 kHz which coincides with the echolocation frequency of sympatric bats. The new genus, named Satizabalus n. gen., is here derived as a new polytypic genus from the existing genus Gnathoclita, based on morphological and acoustic evidence from one described (S. sodalis n. comb.) and two new species (S. jorgevargasi n. sp. and S. hauca n. sp.). Unlike most Tettigoniidae, Satizabalus exhibits a particular form of sexual dimorphism whereby the heads and mandibles of the males are greatly enlarged compared to the females. We suggest that Satizabalus is related to the genus Trichotettix, also found in cloud forests in Colombia, and not to Gnathoclita.

The Austral Predator Katydid—new species of Megatympanon Piza, 1958 (Orthoptera: Tettigoniidae: Listroscelidinae: Terpandrini) from the Brazilian Atlantic Rainforest

Megatympanon Piza, 1958 (Tettigoniidae: Listroscelidinae: Terpandrini) is presently a monotypic genus and the only Terpandrini occurring in South America. The type-species M. speculatum Piza, 1958 is recorded in the Atlantic Forest biome in southeastern Brazil. In this work, we describe an additional species, Megatympanon austroraptorum sp. nov., the second species of the genus, occurring in the Southern Atlantic Forest biome. The new species is described based only on a single male; the female of the new species is unknown. A distribution map of the genus is provided as well as comments on the natural history of the new species.  

An exceptionally preserved 110 million years old praying mantis provides new insights into the predatory behaviour of early mantodeans

Mantodeans or praying mantises are flying insects and well known for their raptorial behaviour, mainly performed by their first pair of thoracic appendages. We describe here a new, exceptionally preserved specimen of the early mantodean Santanmantis axelrodi Grimaldi, 2003 from the famous 110 million years old Crato Formation, Brazil. The incomplete specimen preserves important morphological details, which were not known in this specific form before for this species or any other representative of Mantodea. Unlike in modern representatives or other fossil forms of Mantodea not only the first pair of thoracic appendages shows adaptations for predation. The femora of the second pair of thoracic appendages bear numerous strong, erect spines which appear to have a sharp tip, with this strongly resembling the spines of the first pair of thoracic appendages. This indicates that individuals of S. axelrodi likely used at least two pairs of thoracic appendages to catch prey. This demonstrates that the prey-catching behaviour was more diverse in early forms of praying mantises than anticipated.