Invasive species alert for: Harmonia axyridis and varieties.
Common name(s): Harlequin Ladybird, Multicoloured Asian Ladybird, Halloween Ladybug.
Where and when recorded: There have been two sightings of the Harlequin Ladybird in Ireland during November. The first sighing was reported by a member of the public from a house in Ashford, Co. Wicklow on 04 November 2010. The second sighting was also reported by a member of the public when a single specimen was captured entering a house in Cork City on 11 November 2010.
Has the species been recorded in Ireland/Northern Ireland before? Yes, there were two confirmed records from Northern Ireland in 2007 and 2009. The first of these sighting was in a packet of celery hearts while the second was from a house in Co. Down. Two wild breeding populations hve been identified in Ireland to date.
Has the record/s been verified? Yes, all sightings have been verified by Roy Anderson.
Species description: Harlequin Ladybirds are:
• highly variable in colour (yellow to orange to black)
• variable in number of spots (0-20)
Some of the main features that distinguish it from Ireland’s 15 native species are its:
• larger size of 6-8mm long
• more domed shape than the native species
• usually reddish to brown legs
• can have a distinctive ‘M’ or ‘W’ on the protonum (back of the head)
The two specimens found in Ireland were both of the same variety Harmonia axyridis var. spectabilis which is black with four red spots (see images). This variety looks similar to but is much larger than, the black with red spots form of the native Two-spot Ladybird (Adalia 2-punctata).
Invasive status: Harlequin Ladybird was listed as a most unwanted potential invader in the Invasive Species Ireland 2007 risk assessment.
Introduction status: Established. Two breeding populations have been reported from Cork City (2010 and 2011) and in Co. Carlow (2011).
Distribution Frequency: Rare
Impact: May cause the decline or extinction of Ireland’s native ladybird species. May cause a reduction in biodiversity as the Harlequin Ladybird is known to compete directly with other invertebrates for resources and by predation on small invertebrates including ladybirds, eggs and larvae of butterflies and moths and on aphids and other scale insects. They are an indirect pest of orchard crops which can affect the fruit quality and they can affect the taste of wine as they are difficult to remove from the clusters of grapes prior to harvest. In autumn/winter they tend to swarm and form large aggregations in buildings and are considered a nuisance.
Is there a reference specimen?: Two specimens have been preserved. One has been submitted to the Natural History Museum, Dublin. The second specimen is held by the National Biodiversity Data Centre, Waterford.
Actions taken to date: The specimens were removed from the houses and preserved for reference.
Pathway of introduction: it is unclear how the Harlequin Ladybirds arrived into the Republic of Ireland. It may have been as ‘hitch-hikers’ on imported produce from other infested areas or bought as a biological control agent for other invertebrate species. They can also fly over long distances.
Where might I see it? Entering houses in winter where they can aggregate on windowsills and walls, on imported vegetables, fruit or plants and in gardens, woodlands, agricultural or horticultural lands.
What can you do?:
- Remember that it is against the law to release harlequin ladybird in Ireland
- Do not import, sell or buy harlequin ladybird
- Check imported flowers, fruit and vegetables for the ladybird
- Report sightings of suspected Harlequin Ladybirds
If you think you have seen this Ladybird please first check its identification from the ID sheet below. If possible take a photo of it and its underside if you can and placing it beside a ruler or a coin for scale would also be beneficial. Submit a record of it to the National Biodiversity Data Centre or to the Ladybirds of Ireland survey for verification.
- View Species Alert – please circulate
- View Press release – Dec 2010
- View ID Sheet
- Access Ladybirds of Ireland survey
- View description sheet for native species
This Species Alert has been jointly issued with Invasive Species Ireland