Abstract
The Atlantic Beach-Cricket, Pseudomogoplistes vicentae, inhabits shingle beaches, with a range that extends from the UK to the Canary Islands. Little is known about the natural history of this species, which is listed by the IUCN as Vulnerable. In the present study, a combination of field sampling (by pitfall trapping and direct searching) in spring, summer, autumn and late winter at two different sites in the UK, together with culturing eggs and nymphs in captivity, was used to determine the life cycle. Eggs laid in August in captivity showed no visible embryonic development until May and hatched the following July. There was no difference in the time taken to hatch between eggs maintained over winter at either 4 or 11 °C. Nymphal instars present in the field indicated that the majority of eggs hatch from June to early August. From October to February in the field, the majority of nymphs were estimated to be at the 7th instar. Development appeared to resume by April and nymphs reached adulthood by July to August in the field, two years after the eggs from which they hatched were likely to have been laid. The number of nymphal instars ranged from 10 to 11 (mode: 11) in males and 11 to 13 (mode: 12) in females. In captivity, most adult males died by the end of November, while 35% of females survived until March. Females preferred to oviposit in driftwood rather than in sand in the laboratory. This fact, together with the early embryonic diapause, suggests that the species might be able to disperse by rafting at the egg stage.
Professional fossil preparators at the British Museum (Natural History), 1843–1990