Seeking salt: herbivorous prairie insects can be co-limited by macronutrients and sodium.

The canonical factors typically thought to determine herbivore community structure often explain only a small fraction of the variation in herbivore abundance and diversity. We tested how macronutrients and relatively understudied micronutrients interacted to influence the structure of insect herbivore (orthopteran) communities. We conducted a factorial fertilisation experiment manipulating macronutrients (N and P, added together) and micronutrients (Ca, Na and K) in large plots (30 × 30 m2 ) in a Texas coastal prairie. Although no single or combination of micronutrients affected herbivore communities in the absence of additional macronutrients, macronutrients and sodium added together increased herbivore abundance by 60%, richness by 15% and diversity by 20%. These results represent the first large-scale manipulation of single micronutrients and macronutrients in concert, and revealed an herbivore community co-limited by macronutrients and Na. Our work supports an emerging paradigm that Na may be important in limiting herbivore communities.

Bioacoustics review of Anatolian species of the predatory bush-cricket genus Saga (Orthoptera: Tettigoniidae: Saginae) with the description of a new species.

The genus Saga is a genus of generally large predatory bush-cricket species. It includes 13 taxa in the Palaearctic region. In this research, eight species belonging to Saga (Tettigoniidae, Saginae) were sampled during field studies in different regions of Anatolia of Turkey between 2010 and 2018 (except one specimen). The bioacoustic parameters of these species recorded during the field or in laboratory conditions and the male calling song descriptions, as well as the oscillographic illustrations and distribution maps are given. A new population of Saga found from the South-Eastern Taurus (Hakkari province), which is affiliated to a new species and shows similarity to S. ephippigera, along with the morphological and bioacoustical descriptions of Saga hakkarica sp. n. Sirin Taylan from Turkey, are also given. The relationships between the new species and the closest taxa are discussed using morphological and bioacoustical characters. The structural investigations of the male calling songs reveal three different bioacoustic groups affiliated to eight Anatolian Saga species; as (i) Ephippigera group (S. syriaca + (S. ephippigera + Saga hakkarica), (ii) Natoliae group (S. natoliae + (S. beieri + (S. longicaudata + S. puella) and (iii) S. cappadocica.

Orthoptera assemblages associated with macrophytes of floodplain lakes of the Paraná River

Orthoptera assemblages associated with macrophytes of floodplain lakes of the Paraná River. The Orthoptera assemblage composition varies considerably, depending on habitat type. This study examines the spatiotemporal relationship between plant diversity, hydrometric level, environmental variables and the Orthoptera richness and abundance in floodplain lakes connected permanently or temporarily with the main channel of the Paraná River. The grasshoppers were collected fortnightly (April 2006May 2007). A total of 17 species were recorded and classified according to their frequency of occurrence in constant (7), accessory (4), or accidental (6) species. In the two lakes, the greater species richness and abundance was recorded in summer, thereby coinciding with the highest water level of the Paraná River. The most significant correlation between the orthopteran richness and abundance was with the water level. The aquatic plant richness was significantly different between the lakes, but the vegetation was dominated by Eichhornia crassipes (Mart.) Solms. (Liliales, Pontederiaceae). The lake, which was connected permanently, presented the highest values of diversity and abundance, proving to be a more diverse assemblage. The beta diversity was higher in the temporary connected lake than in the permanently connected one. The orthopterans assemblages were different between the lakes, Cornops aquaticum and Tucayaca gracilis were the species that contributed more to the level of dissimilarity. C. aquaticum was more representative in the lake temporarily connected, while T. gracilis in the permanent connected one. The water level of the Paraná River and the connectivity of the floodplain lakes play an important role to explain the abundance and richness of their orthopteran assemblages.