Megaselia gregaria (Wood, 1910)

DISNEY, R. H. L., 2003, Tasmanian Phoridae (Diptera) and some additional Australasian species, Journal of Natural History 37 (5), pp. 505-639 : 552-555

Megaselia gregaria (Wood, 1910)

(figures 21, 22)

Phora gregaria Wood, 1910: 152 .

This species is widely distributed in Europe (Disney, 1991). The recognition of the male was clarified in the key to British species (Disney, 1989). The wings of the Tasmanian specimens are a little darker than those of European specimens. On the face of it this appears to be a European species, presumably introduced by man into Tasmania. However, apart from the very distinctive hypopygium of M. sullivani (see below) the latter species is almost indistinguishable from M. gregaria , even with regard to unusual details such as the scale-like spinules on the labella (figure 22). If this close phenetic resemblance is due to phylogenetic affinity, and if M. sullivani proves to be a Tasmanian endemic, then this would suggest that M. gregaria may have been introduced to Europe from Tasmania rather than the reverse.

Material

Twenty-three males and 18 females, Tasmania, Hobart, Battery Point , De Witt Street , garden, 23–31 December 1991, 1–11 January 1992 ( R. H. L. Disney —25-4, 6, 7, 34, 38, 39); 1 male, 2 females, Fern Tree, near Hobart, Grays Road, at window of builder’s shed, 18 September 1998 ( RHLD —25-23, 28) .

Natural history

A gravid female had 26 nearly mature eggs. About half the females examined, but none of the males, had the abdomen infested with nematodes.