Scaeva pyrastri is a big hoverfly species when compared to most of the common hoverflies. It has a body length of 12-15 mm.  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.
Scaeva pyrastri is a native species that is present in Madeira, Porto Santo and Desertas. 
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  while S.selenitica can be distinguished because its abdominal markings are more yellowish than the other two species .
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.” 
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