Merodon equestris


Merodon equestris is a Holarctic species of hoverfly.
Like many other hoverflies it displays a colouration pattern similar to a stinging insect as an evolutionary defense mechanism. Other syrphid bee mimics are Mallota, Arctophila, Criorhina, Pocota and Brachypalpus. Merodon species are distinguished from these by the very strong hind femora, which bear a large triangular projection on the underside near the tip. It flies in low vegetation while the other bumblebee mimics prefer higher vegetation layers.

Description

A stout fly with a small head. The tergites are black, without the dust spots or blue-purple sheen of other Merodon species. The thorax and abdomen are hidden by dense, long, erect hairs of variable colouration. Tibia 3 of the male has 2 spurs at the apex. The larva is described and figured by Hodson and it is illustrated in colour by Rotheray.

Distribution

In the Palearctic it is found from Fennoscandia south to Iberia and the Mediterranean basin, and Ireland east through Europe into Russia and Japan. In the Nearctic it is found from British Columbia south to California. It has been introduced to New Zealand.

Biology

Habitat: Open areas in deciduous forest up into the subalpine zone but significantly synanthropic, occurring in suburban parks and gardens and on horticultural land. The adult flies low in April to July with a fast zig-zag flight, among ground vegetation frequently settling on bare ground. Adult M. equestris feed on pollen and nectar. They visit a large variety of flowers for nectar, while the larvae feed internally in tissues of bulbs of Liliaceae, and they are regarded as a horticultural pest, especially of Narcissus. A bibliography of the literature on the biology of M.equestris is given by Barkemeyer

Colour forms