Poljanka Klimaszewski, 1995

Lü, Ting, Du, Si-Le, Luo, Xin-Yu, Ren, Dong & Yao, Yun-Zhi, 2023, A new species of Protopsyllidiidae (Hemiptera, Sternorrhyncha) from the Middle Jurassic of northeastern China, Zootaxa 5396 (1), pp. 41-49 : 42-43

Genus Poljanka Klimaszewski, 1995

Type species. Poljanka shurabensis ( Bekker-Migdisova, 1985) Klimaszewski, 1995

Revised diagnosis. Head width longer than length; eyes large and ovoid; antennae filiform, flagellomeres with 6 or 7 slender segments and one swollen section apically; labium straight, long, three-segmented. Femora stout, distinctly shorter than tibiae; tibiae slender, hind tibiae distinctly longer than fore and middle tibiae; tarsi two-segmented, basal tarsomere longer than apical tarsomere. Forewing narrow at base, wide and round near apex; R branching into R 1 and Rs, R 1 reaching to costal margin; R forked almost equal to M + Cu 1 forked or R forked more distally than M + Cu 1 ( Xu et al. 2023); M forked with two long branches; Cu 1 forked into Cu 1a and Cu 1b, Cu 1a distinctly longer than Cu 1b; cell m 1 elongated, always longer than cell cu 1; anal field long, about half the length of forewing.

Included species. Poljanka shurabensis Becker-Migdisova, 1985 , Poljanka kukalovae Becker-Migdisova, 1985 , Poljanka sharovi Becker-Migdisova, 1985 , Poljanka ventriculosa Becker-Migdisova, 1985 , Poljanka hirsuta Yang et al., 2012 , Poljanka strigosa Yang et al., 2013 , Poljanka curticapillata Lü, Luo & Yao , sp. nov.

Remarks. The family Protopsyllidiidae includes nine genera from the MiddleLate Jurassic ( Aphidulum Handlirsch, 1939 , Asiopsyllidium Becker-Migdisova, 1959 , Cicadellopsis Martynov, 1937 , Cicadopsyllidium Becker-Migdisova, 1959 , Sinopsocus Lin, 1976 , Subaphidulum Klimaszewski, 1995 , Poljanka Klimaszewski, 1995 , Toarcopsyllidium Ansorge, 1996 , Talbragaropsyllidium Li & Frese, 2022 ).

Poljanka resembles Talbragaropsyllidium in forewing size and venation, but differs in the following aspects: flagellomeres 1 to 6 slender and apical section with numerous subsections (vs. antennae slender with 11 segments), body and wings with setae (vs. body and wings without setae), body wider and forewing length 3.85–4.25 (vs. body slender and forewing length 4.84–5.72), bifurcation point of M + Cu 1 before bifurcation point of R (vs. bifurcation point of M + Cu 1 nearly equal with bifurcation point of R), anal field long, almost half of forewing length (vs. anal field short, about one third of forewing length). Poljanka differs from Aphidulum , Cicadopsyllidium , Sinopsocus and Toarcopsyllidium in forewing shorter and broader, length/width ratio about 1.80–1.85 (vs. forewing slender, length/width ratio about 2.57–3.10), differs from Aphidulum , Cicadopsyllidium and Toarcopsyllidium in M forked more basally than Cu 1 (vs. M forked more distally than Cu 1), the branches of M long, about 2.38–2.60 times the length of M (vs. the branches of M short, approximately 0.33–1.00 times the length of M). Poljanka further differs from Toarcopsyllidium in the lack of r-m cross vein (vs. with r-m cross vein), from Cicadopsyllidium in Cu 1a /Cu 1b ratio about 3.46–3.63 (vs. Cu 1a /Cu 1b ratio about 6.44–8.40), and from Aphidulum and Subaphidulum in R 1 not forked (vs. R 1 forked). Poljanka also contrasts with Cicadellopsis in the length of R longer than M + Cu 1 in forewings (vs. the length of R shorter than M + Cu 1). Finally, Poljanka is distinguished from Asiopsyllidium in R 1 not forked (vs. R 1 forked), Rs not forked (vs. Rs forked), the length of R longer than M + Cu 1 (vs. R equal to M + Cu 1). As a result of the poor state of preservation of the above fossils, it’s difficult to make comparisons–aside from wing venation–for the other details of the head, legs, and genitalia.

Key to the species of Poljanka (also see Fig. 1 ).

1 Flagellomeres with 6 slender segments and one swollen section divided into 6 subsections at apex......................................................................................... P. curticapillata Lü, Luo & Yao , sp. nov.

- Flagellomeres with 7 slender segments and one swollen section at apex.......................................... 2

2 M 3+4 bent at the apex abruptly ( Fig. 1G ).................................... P. shurabensis Becker-Migdisova, 1985

- M 3+4 without a sharp bend at the apex..................................................................... 3

3 Forms small, length of forewing 2.8–3.2 mm ............................................................... 4

- Forms large, length of forewing 4.0–5.0 mm................................................................ 5

4 Branches of M slightly shorter than M, bifurcation point of M + Cu 1 parallel to bifurcation point of R ( Fig. 1F ).................................................................................... P. sharovi Becker-Migdisova, 1985

- Branches of M significantly longer than M, about 2.04–4.46 times the length of M; bifurcation point of M + Cu 1 before bifurcation point of R ( Fig. 1E )............................................. P. kukalovae Becker-Migdisova, 1985

5 Both margin and veins of forewing without setae; branches of Cu 1 straight and with an acute angle ( Fig. 1D ).................................................................................. P. ventriculosa Becker-Migdisova, 1985

- Both margin and veins of forewing with setae; branches of Cu 1 not straight and with a right angle..................... 6

6 M forked near 1/3 of forewing base; Cu 1a 7.53 times as long as Cu 1b ( Fig. 1B )................. P. strigose Yang et al., 2013

- M forked near 1/2 of forewing base; Cu 1a 3.60 times as long as Cu 1b ( Fig. 1C )................. P. hirsuta Yang et al., 2012

Figures

FIGURE 1. Forewing line drawings of seven species from Poljanka. A, Poljanka curticapillata Lü, Luo & Yao, sp. nov. B, Poljanka strigosa Yang et al., 2013. C, Poljanka hirsuta Yang et al., 2012. D, Poljanka ventriculosa Becker-Migdisova, 1985. E, Poljanka kukalovae Becker-Migdisova, 1985. F, Poljanka sharovi Becker-Migdisova, 1985. G, Poljanka shurabensis Becker-Migdisova, 1985. Scale bars = 1 mm.