• Question from:Laura

Hi,

On our window sill we have a collection of tiny 1-2mm round insects that look black, but on closer inspection they have yellow spots or stripes.   We also had one bigger one (5mm) that was mostly beige/light yellow with black spots.

They look like tiny black ladybirds/bugs - we haven't seen them fly or jump, but they definitely crawl. Until they move, they just look like black dots of dirt or fluff.

We haven't had any bites from them (no itching either) and they don't move from the window sill - to get rid, we hoover them up, and a few days later more appear in the same spot (10-20 of them at once).

Wondered if anyone could ID them, then we might know how to get rid. 

Cheers, Laura

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  • Posts: 1,105

These are most likely to be varied carpet beetles (Anthrenus). This time of year the adults are pupating and dispersing, so you often find them around windows as they are attracted to the light. These beetles are a common household pest and they will eat dust, hair and wool fibres in your carpets, between floorboards or in upholstery. The best solution is to thoroughly clean everywhere with the vacuum cleaner, not forgetting to move furniture and target nooks and crannies where dust might accumulate. It is unlikely that you will ever get rid of all of them, but it's worth keeping their population down to help prevent damage to your belongings. Look out for wooly-bears, the hairy larval forms - these are when they do most of the damage.