Materials and Methods P albopunctata

The grey bush cricket P. a. albopunctata (Orthoptera: Tettigoniidae) is distributed throughout West and Central Europe (Harz 1969). Its sister subspecies P. a. grisea extends its distribution area into Asia. P. a. albopunctata has an Atlantic-Mediterranean origin, whereas P. a. grisea originates from Central Asia (Ingrisch and Köhler 1998).

P. albopunctata is a thermo- and xerothermophilic species (Harz 1957; Ingrisch and Köhler 1998). In Central Europe, it inhabits dry grasslands and similarly structured semi-arid and arid habitats (Harz 1957). Only in habitats with favourable microclimatic conditions is development of instars sufficiently rapid to provide a reproductive output that enables long-term survival (Gottschalk 1996). In Germany, the species is considered threatened due to the loss of its semi-natural habitats (Ingrisch and Köhler 1998; Walter and Gottschalk 1998). Abandonment of grazing as well as afforestation of dry grasslands has led to habitat loss resulting in relict populations within its distribution area. The life cycle of the species is annual with one generation per year (Ingrisch 1986). Growth, development and reproduction of the cricket are primarily affected by temperature (Ingrisch 1986). Under the environmental conditions in our study area (see below), hatching occurs in spring (mainly April). The reproduction period of the cricket lasts from July until temperatures decline in October (Gottschalk et al. 2003). Females produce eggs throughout their adult life. They prefer soil and moss at places with sparse vegetation as ovi-position sites. Eggs develop during late summer and in the following spring after an intermediate diapause. The proportion of embryonic development that is completed before hibernation depends on the date of oviposition and ground temperature (Gottschalk et al. 2003). Egg hatching after hibernation needs no frost stimulus, but larvae need higher temperatures to hatch (Ingrisch 1985). The first instars of P. albopunctata mainly feed on flowers (anthers, nectar glands, petals). Older nymphs and adults prefer seeds, especially from grasses, and adults also feed on small insects. Both sexes are able to fly.

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