Dineura virididorsata ( Retzius, 1783 )

Macek, Jan, 2015, Descriptions and key to larvae of Central European Dineura (Hymenoptera: Symphyta: Tenthredinidae), Acta Entomologica Musei Nationalis Pragae 55 (2), pp. 787-796 : 794

Dineura virididorsata ( Retzius, 1783)

( Figs 3 , 6 , 9)

Tenthredo viridi-dorsata [sic!] Retzius, 1783: 73 (original description). Dineura virididorsata: ANDRÉ (1880: 90) , ENSLIN (1918), LORENZ & KRAUS (1957), KONTUNIEMI (1960), VERZHUTSKII

(1966, 1981), TAEGER et al. (1998), PSCHORN- WALCHER & ALTENHOFER (2000). Dineura degeeri (Klug, 1817) : DALLA- TORRE (1894: 281, 282), BRISCHKE (1883).

Material examined. CZECH REPUBLIC: BOHEMIA BOR.: Děčínský Sněžník Mt. (5250), 26.viii.2010, 3 larvae on Betula carpatica, E. Kula lgt., J. Macek det. ( NMPC). BOHEMIA CENTR.: Milovice (5755), 6.ix.2004, 1 larva on Betula pendula , 12.ix.2008, 1 larva on Betula pendula ; both J. Macek lgt. & det. ( NMPC) .

Redescription of the last instar larva. Body length 10–14 mm. Colour. Head yellow green, trunk green, upper side above the spiracular line dark green with more or less dark transparent gut content.

Morphology. Head orthognathous with long, slightly curved trichoid setae; labrum symmetrical, with straight anterior margin; labrum and clypeus with four setae; stipes with one seta; palpifer with two setae.

Trunk slightly flattened dorsoventrally with the thorax a little broader than abdomen; subspiracular lobe of second and third thoracic segment more or less enlarged and prominent; setation of body trunk inconspicuous, the setae small, trichoid, distinctly shorter than length of the annulet; the first annulet with two setae; the second annulet with four setae; the fourth annulet with four setae and two glandubae; first postspiracular lobe with one seta and one glanduba; second postspiracular lobe with two setae; subspiracular and surpedal lobes with three setae and one subconical glanduba; suranal lobe with long upcurved dense setae on posterior margin.

Differential diagnosis. The larvae of D. virididorsata are easily identified by their exclusive association with birches, as well as by the inconspicuous body setation (see Key above).

Bionomics. Univoltine; flight period from May to July; larval period from July to October. Food plants: birches ( Betula spp. ) ( BRISCHKE 1883, LORENZ & KRAUS 1957, KONTUNIEMI 1960, VERZHUTSKII 1981, TAEGER et al. 1998, PSCHORN- WALCHER & ALTENHOFER 2000). Habitat: deciduous and mixed forests, birch stands.

Discussion. Larva was described briefly by BRISCHKE (1883) under the name D. degeeri (Klug, 1817) , a junior synonym of D. virididorsata . The bionomics, reproduction and development were treated in detail by VERZHUTSKII (1966).

Figures

Figs 1–3. Dineura Dahlbom, 1835, adults: 1 – D. stilata (Klug, 1816), 2 – D. testaceipes (Klug, 1816), 3 – D. virididorsata (Retzius, 1783). Scale bar: 5 mm.

Figs 4–6. Dineura Dahlbom, 1835, larvae (a – lateral view, b – dorsal view): 4 – D. stilata (Klug, 1816), 5 – D. testaceipes (Klug, 1816), 6 – D. virididorsata (Retzius, 1783). Scale bar: 10 mm.