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Posts Tagged ‘beetle’

Harelquin_Ladybird_Collection

The Manchester Museum’s collection of Harlequin Ladybirds recently acquired under the ongoing museum project ‘Thematic collecting’.

Recently, the Manchester Museum’s Entomology Department acquired some specimens of the Harlequin Ladybird, an invasive beetle species that appeared in Britain (Essex) in 2004 only, but is now a widespread and even dominant species of ladybirds in the UK.

 

Harlequin Ladybird – Harmonia axyridis (Pallas, 1773) (Coleoptera: Coccinellidae) – is a beetle species in the same family with the Seven-spot and Two-spot Ladybirds, both being considered gardener’s best friends as natural enemies of aphids and other garden pests. Harlequin Ladybird was deliberately introduced from east parts of Eurasia, where it is a native species, to many places of continental Europe as a biological agent to control aphids (=greenflies) and scale insects. As Harlequin Ladybird has excellent dispersal abilities (by means of flight), it was just the matter of time until it could have reached the British Isles.

A number of factors have contributed to the successful establishment and dominance of this ladybird species in the UK, particularly, its high reproductive capacity and ability to live in most available habitats. Harlequin Ladybird is also a voracious predator that can feed on other ladybird species.

The UK Ladybird Survey is a citizen science initiative that was launched in 2005, right after the first records of Harlequin Ladybird in Britain had been done. This programme is aimed at encouraging people across Britain to track the spread of Harlequin Ladybird (and other ladybirds) across the UK and submit their records online. Based on this survey, it is clear that by 2014 the Harlequin Ladybird has extended its range by almost half of the country. A decline of seven native ladybird species, which is correlated with the arrival of Harmonia axyridis, has also been demonstrated.

How to control this species and its spread in the UK is a bit unclear. Harlequin Ladybird produces a special, aggregation pheromone to attract other individuals to overwinterwing habitats. It has been proposed to use this pheromone within a network of traps in order to physically withdraw Harlequin Ladybirds from the environment. However, the cost of managing such traps is potentially too high to be feasible. The use of natural enemies of Harmonia axyridis, such as the ectoparasitic mite (Coccipolipus hippodamiae) that is capable to induce sterility in females of Harlequin Ladybirds, has also been considered, but alas with no practical applications so far. Therefore, this species is likely to be staying in the British Isles, apparently becoming another ‘native’ ladybird species with which we are to live (as it already happened with many other insect, crustacean and mollusc species).

Harelquin_Ladybird_Map

The occurrence of Harlequin Ladybirds in Britain from 2004 to 2014 (one dot is equal to 10-km square), after Roy & Brown (2015).

In the following interview, Don Stenhouse, the Curator of Natural Sciences at the Bolton Museum, will share with us his own experience in studying the Harlequin Ladybird.

A full story of the Harlequin Ladybird in the UK can be found in the following paper:

Roy H.E. and P.M.J. Brown (2015), ‘Ten years of invasion: Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) in Britain’ – Ecological Entomology, 40(4): 336–348; online at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4584496/

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Elephant Beetle (Megasoma elephas) is a large striking beetle, belonging to the scarab family and originating from the lowland rainforests in Central and South America. Beetles range between 70-120mm long (or over). The males are usually two/three times bigger than females and their weight can exceed 50-70g.

This is 35 times bigger than the weight of the smallest known mammal, Thailand’s bumblebee bat, which is 11mm long and about 2 grams weight.

The Elephant Beetle males have the large, graceful horns, protruding from their heads, like a trunk of the elephant (this is why their name). The males’ horns purpose is to fight other males for feeding or breeding sites.

Elephant Beetle’s larvae develop in large decaying logs and take up to four years to develop into an adult beetle. The life span of an adult beetle is around four months. Habitat destruction by the man, particularly clear-cutting when large trees are removed, is the main threat to this beetle in nature.

The photographed male is just one specimen from the large Manchester Museum’s collection of scarab beetles, numbering over 3,000 species.

The large male of the Elephant Beetle; it may take up to 4 years to reach maturity.

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