Milichiidae online

In the stem-species pattern of the Milichiidae there are three orbital setae, which are apomorphically lateroclinate. In my opinion, three orbital setae which are latero-reclinate belong to the stem-species pattern of the Chloropidae family-group, because this character state is present in the Acartophthalmidae and several other schizophoran families.
In the stem-species pattern of the Carnidae (present in Neomeoneurites and Meoneurites), there are also three latero-reclinate orbital setae, but there is an additional fourth orbital seta below the others which is slightly medioclinate (Hennig 1972). In Hemeromyia, Meoneura, and Carnus there are two lateroclinate upper orbital setae and two medioclinate lower orbital setae.
In the stem-species pattern of the Chloropidae there are three orbital setae, which in the ancestral state are either all proclinate (Nartshuk 1987), or the upper one is latero-reclinate and the lower ones latero-proclinate (Andersson 1977).
The stem-species pattern of the Milichiidae, with three lateroclinate orbital setae, is present in Costalima, Borneomyia, Microsimus, Phyllomyza, and Stomosis. Within the Milichiidae, the upper orbital seta became smaller and medio-reclinate convergently in Paramyia and in the stem-species of the Milichiinae+Madizinae. The upper orbital seta is lost secondarily in Aldrichiomyza+Xenophyllomyza, Enigmilichia, Litometopa, Milichia distinctipennis, Neophyllomyza, and Ulia poecilogastra. In contrast to this, the upper orbital seta is secondarily enlarged so that it is as long as the lower orbital setae in Pholeomyia, Ulia sp., and some Milichiella species.
I am homologising the lateroclinate upper orbital seta with the medio-reclinate seta because in groups with three lateroclinate orbital setae there is no seta or setula between the uppermost orbital seta and the medial vertical seta, but in several genera with two orbital setae (Desmometopa, Leptometopa, Madiza, Paramyia) there is a small additional medio-reclinate seta above the orbital setae. In addition, there is a large medio-reclinate upper orbital seta present in Pholeomyia and Milichiella lacteipennis.
The inclination of the two lower lateroclinate orbital setae also changes within the Milichiidae. In the stem-species pattern the middle one is slightly reclinate and the lower one is slightly proclinate. However, in the stem-species of Aldrichiomyza+Xenophyllomyza, in Madiza, and in the Milichiinae the middle orbital seta is mainly reclinate and only slightly lateroclinate, and the lower orbital seta is mainly proclinate and only slightly lateroclinate. Where there is only one orbital seta, as in the subgenus Litometopa of Desmometopa and in Ulia poecilogastra, this is latero-reclinate and is therefore probably homologous with the middle orbital seta. It follows that the upper and lower orbital setae are lost in Litometopa and Ulia poecilogastra.
In the type specimen of Ulia poecilogastra and in the other specimens studied, there is only one reclinate orbital seta. According to A. L. Serra (pers. comm.), however, there are three setae (two reclinate and one proclinate) in the Ulia poecilogastra specimen that he studied. Either Serra studied a new species of Ulia or the number of orbital setae is variable in Ulia poecilogastra. In either case there are probably three orbital setae in the stem-species pattern of Ulia, and two were lost within the genus.
Within the genus Costalima, the middle lateroclinate orbital seta became smaller. I suggest that three orbital setae are in the stem-species pattern of Costalima because, according to A. L. Serra (pers. comm.), there is an undescribed Costalima species with three lateroclinate orbital setae. In the type species, C. myrmicola, however, there are only two orbital setae. In my opinion, and on the basis of the position of the setae in a drawing by Serra, the middle orbital seta was reduced in this species.
The configuration of orbital and frontal setae in Eusiphona differs from all other Milichiidae: all the setae together form a uniform row of 8-10 reclinate setae. This is an apomorphy for the genus Eusiphona (from Brake 2000).