HERINGIA 401.

Introduction Heringia are often encountered in dense vegetation in forest edges. They have a swift erratic flight pattern, similar to small black bees, e.g. Halictus. Neocnemodon is merged into Heringia in this key. The lar- vae of H. heringi are predators of gall- forming or leaf-curling aphids and psyl- lids on various trees, e.g. Populus and 402. Ulmus, and fruit trees e.g. Malus, Prunus, and Pyrus. They live within the aphid galls, one larva per gall being normal (see (Speight, 2003) and the reference there- in). The larvae of the subgenus Neocnemodon prey upon coccids, aphids and adelgid plant bugs on coniferous trees, e.g. Picea and Pinus.

Recognition 403. Heringia are small, black close to Pipiza, Pipizella and Trichopsomyia. In Heringia, the abdomen is elongated and the tergites are completely black, in con- trast to most Pipiza and Trichopsomyia. Heringia is close to Pipizella, which has also an elongated third antennal segment. In Heringia, vein tp ends in a sharp angle on R4+5 in the wing, in Pipizella vein tp ends perpendicular to R4+5. In addition, Heringia are blackish at first sight, while Pipizella look brownish. 404.

Key 1.a. Antennae: 3rd segment round, as long as broad (figure 405), in the female somewhat swollen. Male: coxa 2 and trochanter 3 with elongated protuber- ances › 2 1.b. Antennae: 3rd segment elongate, 2-3 times as long as broad (figure 406, figure 407). Male: coxa 2 and trochanter 3 figure 401. Helophilus pendulus, abdomen of without protuberances. 5-7 mm. male. Central and Southern Europe, in Asia to figure 402. Helophilus pendulus, abdomen of Mongolia › Heringia (Heringia) herin- female. gi Zetterstedt figure 403. Helophilus hybridus, abdomen of Note: is treated as a synonym. male. figure 404. Helophilus hybridus, abdomen of female (after Van der Goot, 1981).

122 405. 408.

bm and br entirely covered

409.

406.

bm and br partly bare

figure 408. , wing: basal cells. figure 409. , wing: basal cells (after Van der Goot, 1981).

3.a. Males: sternite 4 with a small promi- nence, sternite 3 flat; metatars 1 cylin- drical, without a depression at the back, 407. tibia 2 without keel; thoracic dorsum mainly white-haired. Females: eye hairs sparse, inconspicuous and pale. 5 mm. Early spring species. Central Europe, in Asia to Pacific coast › Heringia (Neocnemodon) verrucula Collin Jizz: small, black species, legs thin. In early spring on willow catkins. 3.b. Males: sternite 4 flat, without promi- nence, sternite 3 flat; metatars 1 with a depression at the back (figure 410), tibia 2 with keel (figure 411); thoracic dor- sum black-haired, at most with some figure 405. , head of male. scattered white ones. Females: eye hairs figure 406. , head of male. dense, blackish or dark brown. 5.5-7 figure 407. Heringia heringi, head of female mm. Northern and Central Europe (Verlinden). Heringia (Neocnemodon) pubescens Delucchi & Pschorn-Walcher Jizz: small, black species, wings blackish with vio- let sheen. 2.a. Wing: basal cells bm and br and anal Note: if male has metatars 1 without a depression, cell entirely covered by microtrichia sternite 4 flat, but sternite 3 with a prominence, (figure 408); smaller species: 5-7 mm › 3 see N. fulvimanus, 5b, which is in between N. ver- 2.b. Wing: basal cells bm and br and anal rucula and N. pubescens. cell bare at least on first 1/2 (figure 409, microtrichia often present along the 4.a. Males only. Sternite 3 with a keel or venia spuria); mostly larger species: 6-8 prominence › 5 mm, one small species 4.5-5 mm. Only 4.b. Males only. Sternite 3 flat, without males can be identified. › 4 prominence › 6

123