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Orthoptera have some of the largest genomes of all insects. At the same time, the architecture of their genomes remains poorly understood. Comparative cytological data across a wide range of taxa, even for basic parameters such as chromosome number, may provide important insights into the evolution of these genomes and help answer the question of why some species attained such large genome sizes. We collected and compiled more than 1,000 records of chromosome numbers of 339 genera (13.8% of 2,452 known genera) and 769 species (6.2% of 12,250 known species) of Caelifera, the suborder of Orthoptera that includes those taxa with short antennae. Within the family Acrididae, most of the records come from the subfamilies Oedipodinae (N = 325), Melanoplinae (N = 192) and Gomphocerinae (N = 254). Out of the 621 investigated species of Acrididae, 459 (73.9%) shared a chromosome number of 2n♂ = 23. Chromosome numbers of 2n♂ = 17 (12.2%) and 2n♂ = 21 (9.9%) were less common. The remaining 4.0% of species exhibited different chromosome numbers between 2n♂ = 8 (6 + XY) and 2n♂ = 27. Plotted on a phylogenetic tree, our results confirm that chromosome numbers, especially in the largest grasshopper family Acrididae, are highly conserved with a basic count of 2n♂ = 23 (22 + X0), sometimes reduced to, e.g., 2n♂ = 17 (16 + X0) in some genera of the slant-faced grasshopper subfamily Gomphocerinae. Species with divergent chromosome numbers occur in many of the groups we studied, but are not a systematic trait and have evolved multiple times independently. Our study supports the view that chromosome numbers are much more stable across the investigated Caelifera compared to Ensifera, the second suborder of Orthoptera that includes the long antennae bush crickets and crickets. Our results significantly extend our knowledge on the diversity of this character in Caelifera. [ABSTRACT FROM AUTHOR]

The Aegean archipelago is among the largest on Earth with astonishing biodiversity within Europe. Its territory underwent a massive geotectonic transformation in Neogene that resulted in multitude of changes in land-sea configuration and disintegrated the formerly united Aegean land to a complicated mainland-archipelago system. Therefore, it represents an excellent laboratory for studying evolution of terrestrial fauna. In the present study, we use a model group of flightless bush crickets with annual reproduction cycle—Poecilimon jonicus species group—to trace correlation of lineage diversification with the known paleogeographic events in the Aegean area. The group belongs to the hyperdiverse genus Poecilimon and has a disjunct distribution along the Hellenic arc from southwestern Anatolia through Crete to the western Balkans and the Apennines. To test our hypothesis, we inferred phylogenetic relationships of the P. jonicus group sensu lato using a nuclear fragment covering two spacers of the ribosomal cistron (ITS1 + ITS2). To study intra-group phylogeny, we compared mitochondrial phylogenies based on two matrices—(1) a concatenated ND2 and COI dataset of 1656 bp and (2) a 16S rRNA + 12S rRNA dataset of 1835 bp. As a second step, we estimated divergence times applying Bayesian approach with BEAST and a relative rate framework with RelTime on the mitochondrial matrices. We compare trees calibrated based on evolutionary rates and tectonic events and discuss radiation scenarios in concordance with known paleogeographic events in the Aegean area. Our results revealed robust phylogeny of the Poecilimon jonicus group and confirmed a strong link between its evolution and the Aegean paleogeography. The phylogenetic relationships of the group supported reconsideration of its systematics. [ABSTRACT FROM AUTHOR]

Acoustic communication is an essential part of the mate-finding system of many insects, e.g., ensiferan Orthoptera. In this group, the signals consist typically of relatively simple repetitive sound patterns produced for long times and used by the females for a phonotactic approach to the singing males. However, the situation can be different in duetting species where the females respond acoustically to the male. Here, we present data of the songs of 14 East African species of the duetting genus Eurycorypha. These songs are extremely diverse differing in many parameters and containing up to three different syllable types grouped into various echemes. In the duets between males and females, studied in 7 species, the females respond with latency times between 100 and 400 ms and are in some species able to react to different trigger syllables or also to the end of a series of syllables. The males often modify their songs after having heard a female response. Some of these modifications are also produced spontaneously. Similar elements are even found as integral part of the calling song in some species. We interpret these modifications aimed to protect a duet against eavesdropping rivals and thus as part of intrasexual selection. The evolution of the complicated song patterns may thus be driven by the interaction between female choice s.l. and male-male competition. [ABSTRACT FROM AUTHOR]

The data in the Table 1 of the original version of this article were inadvertently shifted during the editing process. Therefore the entries as published in this table did not correspond to their correct data. [ABSTRACT FROM AUTHOR]

The possession of wings and ability to fly are a unifying character of higher insects, but secondary loss of wings is widespread. Within the bushcrickets, the subfamily Phaneropterinae (Orthoptera: Tettigonioidea) comprises more than 2000 predominantly long-winged species in the tropics. However, the roughly 300 European representatives are mainly short-winged. The systematics of these radiations have been unclear, leading to their unreliable formal treatment, which has hindered analysis of the evolutionary patterns of flight loss. A molecular phylogeny is presented for 42 short-winged species and members of all European long-winged genera based on the combined data from three nuclear gene sequences (18S, H3, ITS2). We found four phylogenetic lineages: (i) the first included the short-wing species of the genus Odontura; (ii) a further branch is represented by the South-American short-winged Cohnia andeana; (iii) an assemblage of long-wing taxa with a deep branching pattern includes the members of the tribes Acrometopini, Ducetiini, Phaneropterini, and Tylopsidini; (iv) a large group contained all short-winged taxa of the tribe Barbitistini. Phaneropterinae flightlessness originated twice in the Western Palaearctic, with a number of mainly allo- and parapatrically distributed species of the Barbistini in Southeastern Europe, and the Middle East and a limited number of Odontura species in Northern Africa and Southwestern Europe. Both short-winged lineages are well separated, which makes it necessary to restrict the tribe Odonturini to the West-Palaearctic genus Odontura. Other flightless genera previously included in the Odonturini are placed as incertae sedis until their phylogenetic position can be established. [ABSTRACT FROM AUTHOR]

A new genus is proposed for a new East African Phaneropterinae species, Lunidia viridis, occurring on Mt. Kilimanjaro, Tanzania. Based on 33 records, notes on distribution and habitat are given, as well as acoustical data provided. Climate and vegetation parameters obtained along several transects on Mt. Kilimanjaro were evaluated describing the ecological niche of the new species. This interdisciplinary approach allows not only a profound characterisation of the ecological demands of the new genus but also predictions of the potential distribution area, which is tested for the first time for an African bush cricket species. Lunidia viridis n. gen. n. sp. occurs within humid and perhumid forests and Chagga home gardens, avoiding subhumid conditions on the mountain. It is found from 1,330 m upwards on the southern slopes, whereas the same ecological conditions are expressed from 1,930 m upwards on the drier northern slopes. Lunidia viridis has an unusually complex and variable song, which is described from field and laboratory recordings. The FISH technique for characterizing chromosomes is applied for the first time for an African species; L. viridis exhibits a karyotype typical for most Tettigoniidae. [ABSTRACT FROM AUTHOR]