Melobasis formosa, Carter B. Levey, 1923

Levey, Brian, 2012, 3464, Zootaxa 3464, pp. 1-107 : 24

The formosa species-group

The group is characterised by having the mesoepisternum densely punctured with shallow punctures, partly obscured by long setae ( Fig. 37). Many of the species in the group have the spines bordering the excision of the apical sternite reduced, and in a few species the flange occupies the whole excision or is reduced to a small depressed area on the sternite ( Figs. 7, 8, 198, 215). A reduction in the length of the spines is also found in a number of other groups, and I am uncertain if it is apomorphic in the formosa group. The apical part of the parameres of the aedeagus has fine sensory setae only. The ovipositor of those species examined is short and broad ( Fig. 10). The mid tibia of the male is similar to that of the female, lacking teeth or a setae-filled depression on the ventral face. The tarsal claws lack a well defined basal tooth, but may be broadened at the base.

Some of the species are very variable and the differences between species are small. For this reason I have had to key out a number of species several times in the key. The key provided can only be considered as provisional given the limited amount of material of some species available, and the variability of others. The differences between the aedeagi of the species are often small, the main differences being the relative width to breadth of the aedeagus and the curvature of the lateral margins of the parameres. This group contains 20 species mainly confined to S.W. Australia, also with single species known from N.W. Victoria & inland New South Wales ( M. burnsi sp. n.), and inland New South Wales ( M. formosa Carter ). Adults of many species have been collected on Acacia .

In constructing the key I have included some species of other species-groups which might be mistaken for members of the formosa species-group.