Bug FAQStylops melittae
Stylops melittae · Order: Strepsiptera · Family: Stylopidae
Stylops melittae is a parasitic insect that lives inside sand bees (Andrena). Infested female bees become sterile and look more like males, with reduced pollen-gathering parts and a flatter abdomen. The parasite’s larvae are released onto flowers and are carried back to bee nests with pollen.
Source: Wikipedia
How to recognize it
Parasitized female sand bees are sterile, have a flatter abdomen, reduced pollen-gathering structures, and show male-like coloration.
Source: Wikipedia
Where it lives
It mainly attacks sand bees that collect pollen from many different plant species; specialists on few plants are less often parasitized.
Source: Wikipedia
What it eats
Female Stylops melittae release many mobile larvae onto blossoms, which are then taken to bee nests with pollen.
Source: Wikipedia
Life cycle
After entering a bee, the parasite feeds and molts several times before settling in the abdomen, where its front end breaks through the host’s skin to pupate. Most generations appear in early spring (March-May), though a second generation can occur.
Source: Wikipedia
When you see it
Infested bees are most commonly seen from March through May.
Source: Wikipedia
Lookalikes
Female Stylops melittae show great variation in head-thorax shape, which has led to many mistaken separate species being later merged.
Source: Wikipedia
More photos
Questions people ask
How does Stylops melittae spread to new bees?
The female releases many tiny larvae onto flowers; bees pick them up while foraging and bring them back to the nest.
Source: Wikipedia
When are Stylops-infested bees most common?
They are most often seen in the early months of the year, from March to May.
Source: Wikipedia
What changes occur in a female bee infected by Stylops melittae?
The female becomes sterile, its abdomen flattens, pollen-gathering parts shrink, and its color resembles that of males.
Source: Wikipedia
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Stylops_melittae
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Text written 2026-10-23 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-23.