New species of mole crickets of the Gryllotalpa gryllotalpa group (Orthoptera: Gryllotalpidae) from Israel, based on morphology, song recordings, chromosomes and cuticular hydrocarbons, with comments on the distribution of the group in Europe and the Mediterranean region

Abstract

Two sibling species of mole crickets of the Gryllotalpa gryllotalpa group inhabit Israel. Both are described as new species based on differences in their morphology, acoustic behaviour, chromosome number, cuticular hydrocarbon pattern and habitats. The species with males having 2n = 23 chromosomes, described in the past as the ‘Dead Sea race’, is designated as G. marismortui sp.n. It is an endangered species. In morphology and chromosome number it is similar to G. cossyrensis Bacetti & Capra from Italy, but differs in the composition of cuticular hydrocarbons. Gryllotalpa marismortui occurs in a limited geographical area along the shore of the Dead Sea. Another species, with 2n = 19 chromosomes, is described as G. tali sp.n. and is found throughout Israel. The calling songs of the males of the new species differ markedly. Females of the respective chromosomal numbers discriminate in favour of the homospecific call. Their habitats are strikingly different: G. marismortui lives in hypersaline soil along the Dead Sea shore (total chloride 187.25 meq %), G. tali inhabits freshwater soil (9.31 meq %). The distribution of the twelve known sibling species and one chromosomal race (not yet described) of the G. gryllotalpa group from Europe and the eastern Mediterranean is summarized. The zoogeography and phylogeny of the group are discussed.