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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]

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]

The tettigoniid genus Phlesirtes Bolivar and its allies are reviewed. Morphological, ecological and molecular data prompt the erection of the new genus Chortoscirtes gen.n. with type species Xiphidion meruense Sjöstedt. The genera Phlesirtes, Chortoscirtes, Karniella and Naskreckiella are characterized by morphological characters supported by molecular, acoustic, ecological and chromosomal data. Four species, Chortoscirtes pseudomeruensis sp.n., C. masaicus sp.n., C. puguensis sp.n. and C. serengeti sp.n., are described from localities in northern and coastal Tanzania and one Karniella, K. crassicerca sp.n., is described from Uganda. The following comb n. are proposed: Phlesirtes kibonotensis (Sjöstedt) and Phlesirtes kilimandjaricus (Sjöstedt). Subtribal status is proposed for the four investigated African genera. A key to the Chortoscirtes species is provided. [ABSTRACT FROM AUTHOR]

Two species currently belong to the genus Monticolaria Sjöstedt, 1909 , both of them restricted to submontane and montane forest, forest edge and clearings. In this study a new Monticolaria species is described which inhabits montane forest edge and forest clearings on Mt. Hanang and the Nou Forest reserve (Manyara escarpment) in north-western Tanzania. The first description of the female of Monticolaria kilimandjarica is also provided and a key for the genus is presented. Segments of the mitochondrial gene cytochrome oxidase subunit I (COI) were sequenced to infer phylogeographic patterns. These analyses confirm the genus as a monophyletic group. The calling song and data on the morphology of the stridulatory file of M. kilimandjarica are presented. The evolutionary history of Monticolaria is discussed in light of biogeographical, ecological and morphological data. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 156, 494–506. [ABSTRACT FROM AUTHOR]

This study focuses on the genus Dioncomena and its acoustics, particularly the unique songs produced by male Dioncomena that consist of several distinct elements in a fixed sequence, culminating in a coda that typically elicits a response from a receptive female. We also examine the inflated pronotal lobes, which we term prebullae, that are prominently developed in some Dioncomena species but not in others. We discuss the role of prebullae in the context of acoustic communication in Dioncomena and other related Phaneropterini genera that have similar lateral pronotal lobes. We found that prebullae size is correlated with habitat distribution, with larger prebullae occurring in isolated species while aggregation-prone species have smaller or less pronounced prebullae. Using micro-computer tomography we show sexual dimorphism in the 3D geometry of the acoustic tracheae, being larger in the male. Interestingly, the tracheae are coupled by a septum, like in field crickets, which suggests potential cross talk. We define three groups of Dioncomena based on altitude preferences, ecology, color patterns, and songs: the jagoi-, tanneri-, and ornata-groups. We describe the songs of several species, including newly identified species such as D. flavoviridis sp. nov., D. magombera sp. nov., D. ngurumontana sp. nov., D. sanje sp. nov., D. tanneri, D. versicolor sp. nov., and D. zernyi. We also provide information on the nymphs, development time, and mating behavior of various species reared in the laboratory, shedding light on their phenology and adaptations to their habitats. [ABSTRACT FROM AUTHOR]

A list of the Orthoptera of Miombo woodlands of the Manyara, Dodoma and Tabora Regions of Tanzania is presented. 64 Ensifera species were recorded of which two genera (Kefalia n. gen. with three species newly described; Sentia n. gen., 1 species) and Melidia adfinia n. sp. are new to science. Further 4 new species of Acrometopini are described from the area (Horatosphaga laticerca n. sp., Horatosphaga scalata n. sp., Peronura wottae n. sp., and Tenerasphaga mpwapwae n. sp.). 78 Acridoidea species were recorded. Miombo woodlands are vanishing rapidly these days so that faunal information will become an important tool to measure habitat quality of a certain forested area and for restauration measures. The species Peronura wottae n. sp. and Kefalia grafika n. sp. must be considered as Critically Endangered since only known from Wotta Forest Reserve on the Mpwapwa plateau. This forest reserve is heavily degraded by illegal cutting and lifestock grazing and will disappear in the near future if no immediate measures are taken by responsible authorities.

Eleven new Agraeciini species are described. Six species of Afroanthracites are new to science from the North and South Pare, the West and East Usambara, the Udzungwa Mountains of Tanzania, and the Taita Hills of Kenya. The two Afroanthracites Hemp Ingrisch, 2013 species from the Pare Mountains, A. guttatus n. sp. and A. maculatus n. sp., and A. magamba n. sp., from Magamba Forest Reserve in the West Usambara Mountains are morphologically closely related to each other and form a morphological lineage with the already described species from the West Usambara Mountains (A. discolor Hemp, Ingrisch Ünal, 2013 and A. pseudodiscolor Hemp, 2015) and A. pommeri n. sp. from the Taita Hills of Kenya. A. lineatus n. sp. from Lutindi Forest Reserve in the East Usambara Mountains has its morphologically closest relative in A. jagoi Ünal Hemp, 2013 endemic to the Mazumbai Forest Reserve of the West Usambara Mountains while A. montium (Sjöstedt, 1910) from the Kilimanjaro/Meru area, A. inopinatus n. sp. from the South Pare Mountains and A. usambaricus (Sjöstedt, 1913) from the West Usambara Mountains form another morphological lineage. Morphological traits like the shape of the last abdominal tergite in males, the male cerci and the colour pattern suggest at least two lineages reflecting dispersal of the ancestors at a time when forest connected the mountain ranges in the past during climatic fluctuations. In the genus Afroagraecia Ingrisch Hemp, 2013 new species were collected on Zanzibar and in Kazimzumbwi Forest Reserve, the Udzungwa and Nguru Mountains. Distribution patterns and the morphology suggest recent speciation patterns of Afroagraecia in the Eastern Arc Mountains and along the Tanzanian coast. From the Nguru Mountains a third Dendrobia species of the genus, D. plagata n. sp., is described.

A new Philoscirtus species, P. viridulus n. sp. from forests of the West Usambara Mountains is described and the genus revised. Both species of the genus are known from few localities only. Their habitats are under pressure due to an increasing human population in the East and West Usambara Mountains. Both taxa should be included thus in the IUCN red list of globally threatened taxa to attract more attention to the importance of small forest patches. The biogeographical distribution of species from West Usambaran forests is discussed indicating on one hand that there must have been isolating mechanisms within the West Usambara Mountains and that part of the observed biodiversity in flightless Orthoptera is due to speciation processes not older than approximately 2 million years.

The female of Tropidonotacris grandis is described and information on distribution, habitat, song, chromosomes and nymphal development of this species given. The populations of northern Tanzania all occur in deciduous dry forest, a habitat highly endangered by destruction and therefore T. grandis must be regarded at least as a vulnerable species according to the IUCN red list.