Eosciadocera Hong, 1981

Grimaldi, David A., 2018, Basal Cyclorrhapha In Amber From The Cretaceous And Tertiary (Insecta: Diptera), And Their Relationships: Brachycera In Cretaceous Amber Part Ix David A. Grimaldi, Bulletin of the American Museum of Natural History 2018 (423), pp. 1-97 : 1-97

Eosciadocera Hong

Eosciadocera Hong, 1981: 140 . Type species E. helodis Hong, 1981 (Fushun amber).

DIAGNOSIS: (from Brown, 2002, with modifications) Largest phorids, body lengths 6–7 mm; with many very large, bristlelike setae; frons narrow; 1–4 pairs frontal setae; size of basal flagellomere with little or no sexual dimorphism. Acrostichals, dorsocentrals, postoculars (even setae on tegula) large, thick macrosetae; proepisternum very bristled (10–20 setae). Branches of M 1 and M 2 tubular, not sclerotized; these veins not completely connected. Wing membrane with dense microtrichia overall; proleg stridulatum present; frontal sulcus absent.

TYPE SPECIES: E. helodis Hong , in Early Eocene amber from Fushun, China. Unfortunately, the collection of Fushun amber insects studied by Hong is lost, including the types, and additional specimens of Eosciadocera have not been found in new excavations of Fushun amber ( Wang et al., 2014). It is necessary to rely on the original description.

COMMENTS: There are now three species of Eosciadocera : E. helodis in Fushun amber, E. setosa Brown in Baltic amber (fig. 15), and E. pauciseta , n. sp., also in Baltic amber (fig. 16). The flies are extraordinarily large and bristly, almost like calyptrates, and apparently very rare in Baltic amber. Brown (2002) expressed some doubt about the sciadocerine position of the genus, but later included Eosciadocera in this subfamily ( Brown, 2007a). Courtesy of Christel Hoffeins, who loaned the paratype of E. setosa (CCHH 1358-1: fig. 15), I was able to observe the stridulatum in this species. There are considerable differences between the two Baltic amber Eosciadocera species (listed in the diagnosis below), but I am placing the new species in this genus given the striking similarities between the two, such as the uniquely large size and numerous, large macrosetae.