S. Mahunka szerk.: Folia Entomologica Hungarica 48. (Budapest, 1987)

Selecting the specimens from the bark in the field proved to be inadequate due to considerable loss especially of younger larvae, therefore bark samples were individually taken to nylon bags and investigated in the laboratory with naked eye or with stereomicroscope

. Speciemens were preserved in 70% isopropyl alcohol. Hymenoptera parasites were reared from eggs left on small pieces of bark, in glass vials watered daily. Different larval instars were investigated by light microscope and by JEOL JSM scanning electron microscope. Measurements were taken from dried, prepared specimens with the help of an eyepiece micrometer. Statistical analyses were made by SVÁB (1981) and SOUTHWOOD (1984). Results 1. Distribution in Hungary The species came out from practically all samples taken in any part of Hungary, in the mentioned localities with a high abundance (500 -900 individuals/tree) which, according to BRAMMANTS (1975) does affect growth of the tree. 2. Postembrional development The results of morphological investigations are presented, also for practical reasons, in the most concise form, in an identification key of all instars and of both sexes of L5 and adult stages. The best characters were found on the antenna, rostrum, eyes, meso- and metathorax, tip of abdomen and in the measurements (Table 1), corresponding figures were published by VÁSÁRHELYT (1983, Figs 1-2). Table 1. Measurements and ratio of measurements of different body parts in the developmental stadia (measurements in mm) Ll L

2 L

3 L

4 L

5 Ó* ? length of body 1 .04 1 .46 1.98 ? .70 3 .71 3 .86 4.70 length of head 0 .27 0 .40 0.51 0 .65 0 .80 0 .85 1.00 width of head 0 .37 0 .42 0.54 0 .69 0 .87 0 .89 1.00 length of pronotum 0 .08 0 .09 0.13 0 .19 0 .30 0 .44 0.52 width of pronotum 0 .45 0 . 51 0.71 0 .92 1 .28 1 .27 1.44 length of scutellum 0 .65 0.75 width of scutellum 0 .51 0.63 length of mesonotum 0 .06 0 .09 0.13 0 .23 0 .43 width of mesonotum 0 .48 0 . 55 0.73 0 .97 1 .56 width of abdomen 0 . 55 0 .66 0.94 1 .21 1 .71 i .66 2.18 I

. of ant

. j oi nt 1 0 07 0 .07 0.09 0 .12 0 .15 0 .16 0.18 I

. of ant. joint 2 0 .07 0 .08 0.10 0 .15 0 .23 0 .32 0.38 1. of ant

. j oi nt 3 0 0 7 0 .07 0.10 0 .13 0 .19 0 .24 0.28 1. of ant

. j oi nt 4 0 14 0 . 16 0.19 0 .22 0 .27 0 .28 0.31 head 1/w 0 73 0 .95 0.94 0 .94 0 .92 0 .96 1.00 a. joint 2/w of head 0 19 0 .19 0.19 0 .22 0 .26 0 .36 0.38 a. joint 4/w of head 0 38 0 .38 0.35 0 32 0 .31 0 .32 0.31 pronotum l/w 0 18 0 .18 0.18 0 21 (t 23 0 35 0.36 mesonotum l/w 0 13 0 .16 0.18 0 24 0 28 w of abd./w of head 1 49 1 . 57 1.74 1 75 1 97 1 87 2.18 I of body/w of head 2 BI 3 .48 3.67 3 91 4 26 4 34' 4.70 N = 3 4 3 10 10 10 10 1 (6) External genitalia fully developed, abdominal segments 9 and 10 in repose not visible. Hemelytra and scutellum distinct. Antennái formula 16 : 3? : 24 : 28. Tibial comb of fore leg comprising 4-5 bristles. (Adults)