Spotted Thintail (Meliscaeva auricollis)

Spotted Thintail Hoverfly (Meliscaeva auricollis) Wing length 6-9.5mm. Flight all year.

Species to spot in February

Like my previous blog on the Marmalade hoverfly (Episyrphus balteatus) this is also a hoverfly that can be spotted all year round but generally peaks mid-summer with numbers boosted by incoming migrations. Being only the start of February when I write this article, they have already been spotted and reported on social media sites. So, on the next warm day I intend to find a sunny hotspot in the hope of getting a glimpse of one after awakening from its winter torpor. 

It’s a smallish hoverfly, a little bit smaller than the Marmalade, and prefers hanging out around vegetation at a woodland edge rather than in a garden, but they can quite commonly get spotted around shrubs in an urban park. I have spotted them around my garden honeysuckle on occasion. If you live in the Mediterranean, you might find it pollinating the flowers of the Mastic tree (Pistacia lentiscus). Its presence becomes increasingly scarce the more northerly you travel through the UK into the Scottish Highlands and westward into Ireland.

In my research for these articles, I love coming across other common names used for hoverflies, some I adopt and others not so. Here I have gone with the common name Spotted Thintail a representation of its observable characteristics in comparison to others of the same genera within Europe. The other European hoverfly in this genus being the Banded Thintail (Meliscaeva cinctella). Normally in the UK this hoverfly is commonly known as just the Spotted Meliscaeva, so adding thintail ties it to its cousin. In Finland it is often referred to as Kultamesikirvari which translates as ‘golden honey hoverfly’ and in Sweden ‘Kragfickblomfluga which translates as ‘collar-girl flower-fly’ which is also a nice name. The Dutch call it the Variable Pixie (or Variabel elfie) emphasising the variability in appearance which I will discuss in more depth shortly.

Typically, the adult Spotted Thintail is a slender species with a shiny thorax, yellow scutellum with a darkish centre, elliptical yellow markings on tergite 2, with oblique spots in tergites 3 & 4 which can sometimes form bands across the abdomen. Another feature to observe are yellow lunules below black frons, above the antennae on a yellow face, see below. 

Credit: Sander Bot and Frank Van de Meutter

The larvae are aphidophagous, which means they prey on aphids and have a particular fondness for Rosy Apple Aphid (Dysaphis plataginea), so inviting the adults to visit an orchid or apple tree in the garden could be beneficial. Larvae are also fond of the aphids commonly known as Alder suckers (Psylla alni) typically associated with Alder tree (alnus glutinosa), and are easily observable with their long antennae and wavy white secretions often covering the lower half of their body. In the UK this hoverfly is strongly associated with Gorse, Broom and Umbellifers and later in the season Ivy.

The Spotted Thintail like the Marmalade hoverfly are affected by temperature during development, a term called temperature-dependent phenotypic plasticity. So, if it is cold the emerging adult will be much darker in both scutellum and the abdomen banding than a summer brood. I don’t have a photograph of one of those darker ones and to my knowledge I haven’t seen one in my 10 years of study, so its spotting high on the list for this year. I will let you know if I come across one. Being a lot of variability within this species they can be easily overlooked or mis-identified. They can be often confused with the much less frequent Ringed Beech Hoverfly (Melangyna cincta) which has triangular marking on its abdomen or Platycherius species, these having black not yellow faces, so a quick check on these features is required.

Sources:

Dejana Stanic: Plant Protection Science: The predators of aphids on apples in the region East Sarajevo (Bosnia and Herzegovina) (2024): An article identifying M. auricollis as a key predator in apple orchards.

S.  Rojo &  M.  A.  Marcos-Garcia: Syrphid predators (Dipt.: Syrphidae) of gall forming aphids (Hom.: Aphididae) in Mediterranean areas: Implications for biological control of fruit trees pests (1997): An article exploring the role of syrphid larvae in controlling aphid pests in Spain.

Sander Bot and Frank Van de Meutter: Hoverflies of Britain and North-West Europe: A Photographic guide 2023, Bloomsbury Wildlife.