Basal Cyclorrhapha In Amber From The Cretaceous And Tertiary (Insecta: Diptera), And Their Relationships: Brachycera In Cretaceous Amber Part Ix David A. Grimaldi
Author
Grimaldi, David A.
Division of Invertebrate Zoology American Museum of Natural History, New York
text
Bulletin of the American Museum of Natural History
2018
2018-10-24
2018
423
1
97
http://www.bioone.org/doi/10.1206/0003-0090-423.1.1
journal article
7631
10.1206/0003-0090-423.1.1
2e886aea-b59a-45a6-aeaa-2427d584a894
0003-0090
4613008
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.