DIPTERA > BRACHYCERA | Higher Diptera

MUSCOMORPHA > SCHIZOPHORA > Calyptratae > Muscoidea > Anthomyiidae (246 species)

(subfamilies: Anthomyiinae and Pegomyiinae)

This final page is for coastal anthomyiid species, specifically, although not exclusively, of the genus Fucellia.

There are around twenty described species and, in some regions where many can be encountered such as North America, they are placed in their own subfamily Fucelliinae. In Britain we only have three species Fucellia fucorum, Fucellia maritima and Fucellia tergina, which are listed in the Anthomyiinae > Anthomyini tribe.

Fucellia is a specialised strandline genus associated with washed-up wrack, especially decaying brown Fucus seaweed, where they will breed and in which the larvae will develop. Unlike most anthomyiids, the eyes of the males are dichoptic - broadly separated, as in the females - which makes identification tricky from photos unless you can see a distinct basal swelling at the base of the hind femur. The costa of the wing has a series of short, well-spaced coarse setae beyond the subcoastal break, sometimes clearly visible in photos, but often hard to see.

Fucellia fucorum is described as the darker of the three species with entirely black legs and with jowls that are usually deeper than the height of the eye. The confirmed records and associated distribution maps show that it is very much a species of northern and western coasts.

Fucellia maritima and Fucellia tergina both have yellowish-brown tibia at least in the proximal (basal) third. Males are best separated by the structure of the hind femora but, until I have photos to view and/or compare, I'm not sure about the detail. Females may not be separable. The best visual indicator is the depth of the jowls where in Fucellia maritima the eyes are said to be slightly smaller, resulting in a wider parafacial that, according to Steven Falk, makes the jowls about equal to the height of the eye. Fucellia tergina has larger eyes with a correspondingly narrower parafacial and jowls that are markedly less deep than the height of the eye. The difference is such that Steven Falk refers to the latter as the Narrow-jowled Strandline Fly. The official 'key' on the other hand puts the gena (jowl) height as 0.6-0.7 times the eye height in Fucellia maritima and 0.5-0.65 times in Fucellia tergina, which doesn't quite equate to Steven Falk's description.

The photos featured below of a few individuals photographed on the Solent strandline at Calshot have been viewed and deemed to be correct.

Although I suspect that they will remain as unidentified, I've included a few more photos of anthomyiids that I've found on the beach. It seems a bit strange to me that they should be in this habitat unless there's some association so, purely for future reference, I thought I'd add them rather than leave them filed on my hard drive.    

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New page, Dec.24 (v.1)