The mass emergence of Hoplia philanthus Fuessly (Scarabaeidae)

摘要

On 16 June 2015 at between 9am and 11am, before the sky clouded over, hundreds of Hoplia philanthus Fuessly started to emerge from mown areas of meadowland which we have created in our garden. We first noticed specimens of Hoplia in 2003 and gradually over the last 12 years the numbers have increased exponentially. We created meadowland over 30 years by just letting the lawn grass grow, letting the flora seed and then cutting the hay and removing the cuttings. We have introduced one specimen of yellow-rattle Rhinanthus minor and one specimen of cowslip Primula veris, which we rescued from a farm track, and which have now spread throughout the meadow. Species like the common spotted orchid have just arrived and there are large ant mounds of the species Lasius flavus (Fabricius) associated with meadows. We have, of course never used any fertilizers. By cutting pathways through the meadows it defines the meadow areas, makes it look neat and tidy but also creates areas for the chafers to colonise.