Crickets (Insecta, Orthoptera, Grylloidea) from Southern New Caledonia, with descriptions of new taxa.

Intensive sampling of cricket communities has been undertaken in southern New Caledonia in selected plots of vegetation, i.e. rain forest, preforest and maquis shrubland. This leads to the discovery of many new taxa, which are described in the present paper, together with closely related species from nearby areas. Descriptions are based on general morphology and characters of genitalia. Calling songs are described for all acoustic taxa but two, and observations about species habitats are given. In total, 35 species belonging to 13 genera are studied, including 21 new species and two new genera. The pattern of assemblages of cricket species in New Caledonia is discussed.

Old Lineage on an Old Island: Pixibinthus, a New Cricket Genus Endemic to New Caledonia Shed Light on Gryllid Diversification in a Hotspot of Biodiversity.

Few studies have focused on the early colonization of New Caledonia by insects, after the re-emergence of the main island, 37 Myr ago. Here we investigate the mode and tempo of evolution of a new endemic cricket genus, Pixibinthus, recently discovered in southern New Caledonia. First we formally describe this new monotypic genus found exclusively in the open shrubby vegetation on metalliferous soils, named 'maquis minier', unique to New Caledonia. We then reconstruct a dated molecular phylogeny based on five mitochondrial and four nuclear loci in order to establish relationships of Pixibinthus within Eneopterinae crickets. Pixibinthus is recovered as the sister clade of the endemic genus Agnotecous, mostly rainforest-dwellers. Dating results show that the island colonization by their common ancestor occurred around 34.7 Myr, shortly after New Caledonia re-emergence. Pixibinthus and Agnotecous are then one of the oldest insect lineages documented so far for New Caledonia. This discovery highlights for the first time two clear-cut ecological specializations between sister clades, as Agnotecous is mainly found in rainforests with 19 species, whereas Pixibinthus is found in open habitats with a single documented species. The preference of Pixibinthus for open habitats and of Agnotecous for forest habitats nicely fits an acoustic specialization, either explained by differences in body size or in acoustic properties of their respective habitats. We hypothesize that landscape dynamics, linked to major past climatic events and recent change in fire regimes are possible causes for both present-day low diversity and rarity in genus Pixibinthus. The unique evolutionary history of this old New Caledonian lineage stresses the importance to increase our knowledge on the faunal biodiversity of 'maquis minier', in order to better understand the origin and past dynamics of New Caledonian biota.

Zebragryllus Desutter-Grandcolas & Cadena-Casteñada, n.gen. a new Gryllinae genus from Eastern and Western Amazonia, South America (Orthoptera, Grylloidea, Gryllidae).

We describe a new genus of grylline cricket, Zebragryllus Desutter-Grandcolas & Cadena-Casteñada n. gen., from the Neotropical Region, using characters of morphology and male genitalia; genitalic characters clearly show that Zebragryllus n. gen. is closely related to Anurogryllus Saussure, 1878. Six species are described as new to science, originating from western (Peru, Colombia) and eastern (French Guiana) Amazonia: Zebragryllus fuscus Desutter-Grandcolas, n. sp., Z. guianensis Desutter-Grandcolas, n. sp., Z. intermedius Desutter-Grandcolas, n. sp., Zebragryllus nauta Desutter-Grandcolas, n. sp., Zebragryllus nouragui Desutter-Grandcolas, n. sp., and Zebragryllus wittoto Desutter-Grandcolas and Cadena-Casteñada, n. sp., type species of the genus. They are characterized by their size, coloration (shining black, most often with white patterns of coloration, hence the genus name), and male and female genitalia. The calling songs of Z. guianensis Desutter-Grandcolas, n. sp., Z. intermedius Desutter-Grandcolas, n. sp., Z. nouragui Desutter-Grandcolas, n. sp., and Z. wittoto Desutter-Grandcolas and Cadena-Casteñada, n. sp. are described. An identification key is proposed for both males and females.