cf. Aeshna sp.

(Figure 3 (a, b))

Material

SMMG Ku 398 (a nearly complete fore wing lacking base and parts along posterior margin, preserved in brown diatomite), collection of Senckenberg Naturhistorische Sammlungen Dresden, Saxony, Germany .

Age and outcrop

Early Oligocene (Rupelian – Chattian), Ústí Formation, Středohoří Complex, Kundratice near Litoměřice (Figure 1), Czech Republic (see Kvaček and Walther 1998).

Description

A nearly complete fore wing, with only basal anterior area and parts along posterior wing margin missing; wing surface apparently hyaline; wing c. 52 mm long (assumed from fragment) and 17.5 mm wide; distance from estimated base to nodus c. 25.3 mm; distance from nodus to wing apex, c. 26.6 mm; nodus nearly midway between base and apex; distance from nodus to pterostigma 17.4 mm; distance from pterostigma to apex about 5.6 mm; pterostigma rather long, 4.0 mm long and 0.9 mm wide, covering approximately five cells; pterostigmal brace obliquely aligned with proximal side of pterostigma; 20 postnodal cross-veins, not well aligned with 16 visible subpostnodal cross-veins; 12 visible antenodal crossveins of first row between C and ScP not aligned with one visible corresponding antenodal cross-veins of second row between ScP and RA; hypertriangle crossed by three or more cross-veins; median space free, partly preserved; submedian space crossed by two cross-veins, subdiscoidal triangle twocelled; discoidal triangle elongate and divided into five small cells, its costal side being 6.6 mm long, distal side 5.9 mm long and proximal side 2.8 mm long; width of postdiscoidal area just behind discoidal triangle 3.4 mm, width along posterior wing margin 7.2 mm; three rows of cells in postdiscoidal area just distal of discoidal triangle; convex supplementary sector (trigonal planate) in postdiscoidal area, aligned with concave Mspl; Mspl well defined, undulated; two or three rows of cells between Mspl and MP and also between Mspl and MA; bulge in distal part of MA (‘ aeshnid bulla ’) apparently weaker than in Aeshna zlatkokvaceki sp. nov., but it is too poorly preserved to be accurately described; five preserved Bq cross-veins; oblique vein ‘ O ’ one cell distal of base of RP2; Rspl well defined and nearly straight; area between Rspl and IR2 with three rows of cells in its widest part; IR2 smoothly curved distally and asymmetrically forked 5.0 mm proximad of pterostigma, with three rows of cells between its branches; RP2 strongly curved posteriorly opposite proximal side of pterostigma; one row of cells between RP2 and anterior branch of IR2; IR1 nearly straight beginning just below proximal posterior edge of pterostigma; one row of cells between MP and CuAa in basal parts, but with about five or six along posterior wing margin; CuAa with circa six posterior branches directed towards posterior wing margin, but not preserved; cubitoanal area poorly preserved, but distinctly broad with about seven rows of cells below CuAa.