Discovery of the most ancient member of family Tanyderidae (Diptera) from the Lower Jurassic (Sinemurian) of England
Author
Skibińska, Kornelia
Author
Krzemiński, Wiesław
Author
Coram, Robert A.
text
Zootaxa
2014
3857
1
125
130
journal article
10.11646/zootaxa.3857.1.6
f134bbeb-a658-4640-9687-04a86526fb23
1175-5326
227424
C11922A0-154E-4026-BEA2-261358622FD0
Nannotanyderus oliviae
Skibińska, Krzemiński & Coram
sp. nov.
(
Figs. 2–5
)
Etymology
. The new species name is dedicated to Olivia, daughter of Robert Coram.
Type
material.
Holotype
No. I-F/MP/
2/1621/13
, complete wing;
Paratype
No. I-F/MP/
1/1600/12
, wing lacking anal lobe below A1 vein. Both from Brooki Bed, Shales-with-Beef Member, Charmouth Mudstone Formation, Lias Group (Lower Sinemurian, Turneri zone, Brooki subzone), Monmouth Beach, Lyme Regis, Dorset,
UK
(national grid reference SY 334 914).
Diagnosis.
The new species differs from all other members of the genus in that veins Rs, R4+5 and R4 form a nearly straight line, and vein R4+5 is shorter than in other described species. It also differs from
N. grimmenensis
and
N. ansorgei
in that Sc terminates on the wing margin before fork of Rs into R2+3 and R4+5, from
N. krzeminskii
and
N. kubekovensis
in that m-cu is more distal to the fork of M3+4 into M3 and M4, and from
?
N. incertus
in that Rs is shorter. The anal lobe is also more developed than in
N. krzeminskii
and
N. ansorgei
(not known in other species).
Description.
Holotype
. Wing length
2.8 mm
. Sc short, extending half wing length, ending before fork of Rs into R2+3 and R4+5; R2+3 1.6 times longer than Rs and 2.6 times longer than R2; Rs as long as R3 and forming straight line with vein R4; R5 originates directly from R4 a short distance distal to its fork from Rs; vein M1 about 1.3 times longer than the upper edge of d cell; m-cu leaves M4 distal to the fork of M3+4 into M3 and M4. Explicit anal lobe.
Remarks.
Although similar to other
Nannotanyderus
species, in particular
N. krzeminskii
, the observed wing venation differences and significantly older age (in excess of 12 Ma), justify the description of a new species for the English material.