Melanogaster hirtella (Loew, 1843)
Chrysogaster hirtella (Loew) in Stubbs & Falk (1983).
Biology & ecology:
The larva is aquatic, inhabiting mud adjacent to emergent plants such as Greater Reedmace Typha latifolia and Reed Sweet Grass Glyceria maxima, but especially favouring Marsh Marrigold Caltha palustris, usually at the edges of running water. It has modified hind spiracles which are used to gain access to the air spaces in the submerged parts of emergent plants. Found in marshes or near the margins of running water where there is lush emergent vegetation. Adults are usually swept from waterside vegetation or found visiting flowers, especially white umbels, and buttercups Ranunculus sp.
Widespread and common but apparently far less abundant east of the Pennines. This would conform to the analysis by Speight (2010) who reports this as an Atlantic seaboard species which is quite scarce in central and southern Europe.
Status & conservation:
Some indication of decline from the mid 1980s, similar to many other wetland species. It can be extremely abundant where it is found, but it is often necessary to sweep low-growing flowers to secure specimens. It has been