Isoperla kozlovi ZHILTZOVA, 1972

Zwick, P & Surenkhorloo, P, 2005, The Mongolian Species Of Isoperlinae (Plecoptera: Perlodidae), Acta Zoologica Academiae Scientiarum Hungaricae 51 (3), pp. 253-276 : 273

Isoperla kozlovi ZHILTZOVA, 1972

( Fig. 11 )

Isoperla kozlovi ZHILTZOVA, 1972 , Nacekomye Mongol.: 134, figs 13–15.

Isoperla kozlovi – ZHILTZOVA & ZAPEKINA-DULKEIT, 1986, Keys to the insects of the Soviet Far East 1: 187–188.

Material studied. MONGOLIA: Selenge aimak, Eroo sum, Minj River [49°00’N, 108°02’E] 1 f, 02.VII.2001 ; Mandal sum, Khonin Nuga, Eroo River [49°05’N, 107°17’E], 1 m, 4 ff 14.–18. VI.2002 ; 1 f, 02.VII.2002; 1 m, 16. VI.2003; 1 m, 1 f, 04.VII.2003 (leg. P. SURENKHORLOO).

Size. Fore wing length 10–10.5 mm ( ZHILTZOVA 1972).

We supplement the original description by an illustration of the patterns of head and pronotum ( Fig. 11a ), details of the penial armature, and of the egg.

Male. ZHILTZOVA (1972) had shown the penis sclerites inside sternite 9, as seen by transparency. When the penis is artificially everted ( Fig. 11b ), details become visible. Each of the large paired sclerites consists of a longitudinal bar resting in the membrane with an erect, hollow spine-covered process near the distal end. The rest of the penial membrane is covered with a variety of spicules (some of them frazzled) and teeth.

Female. Subgenital plate broad, distinctly projecting, distal margin sinuous, with a shallow median notch, as shown in the available descriptions.

Egg ( Figs 11 c-e). Oval, about 330 µm long, collar included. Collar with a few subdued meshes, edge simple, base smoothly bulging into interior of egg. Chorion smooth, about 3 µm thick. No micropyle seen.

Diagnostic characters and affinities. ZHILTZOVA commented on the resemblance of male genitalia with Kaszabia spinulosa Raušer. Indeed , both have longitudinal penial sclerites carrying an erect barbed hollowed finger at the end; see below.

Figures

Fig. 11. Isoperla kozlovi ZHILTZOVA. a = head and prothorax, b = artificially everted penis membrane with major sclerites, details of marginal spinules enlarged, c = egg; d, e = collar enlarged