Hoverfly, Scaeva pyrastri

Scaeva pyrastri is a big hoverfly species when compared to most of the common hoverflies. It has a body length of 12-15 mm. [1] Along with its large size for me what is quite distinct is that the abdominal markings are whitish (most hoverflies have yellowish markings) which produces a strong contrast.

In this video, filmed at Poiso, you can see a Scaeva pyrastri nectaring flowers of Ulex europaeus. His markings are very impressive and allow us to identify it as a species.

Hoverflies mimic wasps and bees but they do not sting, they are harmless.

They can hover like an helicopter and they can also change direction very rapidly in the air almost like a UFO. Its back markings can be observed when it is hovering and sometimes if it keeps still for enough time the species can even be identified this way. They can be found nectaring and hovering around flowers. Adults feed on the nectar of flowers but larvae feed on aphids. This means that hoverflies are beneficial insects that are very important both for flower pollination and for the fight against aphid pests.

Scaeva pyrastri is a native species that is present in Madeira, Porto Santo and Desertas. [2]

In Madeira Islands there are two more species of the genus Scaeva: Scaeva albomaculata and Scaeva selenitica. Contrary to S.pyrastri, S.albomaculata presents a yellow stripe on the sides of the torax [3] while S.selenitica can be distinguished because its abdominal markings are more yellowish than the other two species [4].

It is curious that the genus Scaeva is not present in Azores:

“The absence of genus Scaeva in the Azores is surprising because these hoverflies are strong flyers and have been cited from all the other Macaronesian islands.” [5]

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