Phylum Arthropoda (Arthropods) ➔ Subphylum Hexapoda (Hexapods) ➔ Class Insecta (Insects) ➔ Order Coleoptera (Beetles) ➔ Family Chrysomelidae (Leaf beetles)

Chrysolina (Sphaeromela) varians (Schaller, 1783)

Veränderlicher Johanniskraut-Blattkäfer

Synonyms:

Chrysomela varians Schaller, 1783 | Chrysomela malleti Jaquet, 1935 | Chrysomela nigricollis Mallet, 1936 |

  • Chrysolina varians  5473
    Chrysolina varians (Schaller, 1783)  Veränderlicher Johanniskraut-Blattkäfer   
    Chrysolina varians
    DE, Chemnitz, Zeisigwald; 2012-07-09 16:57:59
    Image number: 5473

    DE, Chemnitz, Zeisigwald
    2012-07-09 16:57:59

  • Chrysolina varians  6219
    Chrysolina varians (Schaller, 1783)  Veränderlicher Johanniskraut-Blattkäfer   
    Chrysolina varians
    DE, Chemnitz, Zeisigwald; 2013-07-22 10:21:02
    Image number: 6219

    DE, Chemnitz, Zeisigwald
    2013-07-22 10:21:02

  • Chrysolina varians  3069
    Chrysolina varians (Schaller, 1783)  Veränderlicher Johanniskraut-Blattkäfer   
    Chrysolina varians
    DE, Chemnitz, Zeisigwald; 2009-06-07 11:34:37
    Image number: 3069

    DE, Chemnitz, Zeisigwald
    2009-06-07 11:34:37

  • Chrysolina varians  3070
    Chrysolina varians (Schaller, 1783)  Veränderlicher Johanniskraut-Blattkäfer   
    Chrysolina varians
    DE, Chemnitz, Zeisigwald; 2009-06-07 11:34:23
    Image number: 3070

    DE, Chemnitz, Zeisigwald
    2009-06-07 11:34:23

  • Chrysolina varians  4090
    Chrysolina varians (Schaller, 1783)  Veränderlicher Johanniskraut-Blattkäfer   
    Chrysolina varians
    DE, Chemnitz, Zeisigwald; 2010-06-20 12:49:07
    Image number: 4090

    DE, Chemnitz, Zeisigwald
    2010-06-20 12:49:07


Classification:
Chrysolina varians belongs to the subfamily Chrysomelinae, tribe Doryphorini.
Distribution:
Europe, Algeria, Turkey, east to Western Siberia.
Habitat:
Forest clearings, forest edges, light forests, grassland - on St. John's wort.
Description:
Length 4.5 - 6.0 mm; body roundish, only slightly longer than broad; upper side green, blue, violet or copper red with bronze shine, rarely black; pronotum and elytra finely dotted; pronotum without set-off lateral bulge, sides clearly rounded.
Biology:
Chrysolina varians lives oligophagus mainly on common St. John's wort (Hypericum perforatum), spotted St. John's wort (Hypericum maculatum) and St. John's wort (Hypericum dubium). Other host plants are winged St. John's wort (Hypericum tetrapterum), hairy St. John's wort (Hypericum hirsutum) and slender St John's-wort (Hypericum pulchrum).
Since the species only needs about 6 weeks for development and does not undergo summer dormancy, several generations (in Central Germany usually 2) per year can be formed under suitable conditions. The nocturnal imagines can be found from the end of April to September. The beetles rarely fly and cause feeding damage in the leaves of the host plants. The females, which are ovoviviparous in cooler regions, lay reddish eggs in warmer regions. After hatching, the larvae pass through 4 larval stages in 18 - 22 days and pupate on the ground. The pupal period lasts 7 - 16 days. Chrysolina varians normally hibernates as an imago.
Natural enemies:
Some species of the tachinid fly genus Macquartia, Meigenia mutabilis (Fallen, 1810) (Diptera: Tachinidae).
The ichneumonid wasp Mesochorus giberius (Thunberg, 1822) (Hymenoptera: Ichneumonidae).

References, further reading, links:
  1. Rheinheimer, Joachim, & Hassler, Michael: Die Blattkäfer Baden-Württembergs, 2018, 928 pages, Kleinsteuber Books (Karlsruhe), ISBN 978-3-9818110-2-5
  2. Arved Lompe: Die Käfer Europas - Ein Bestimmungswerk im Internet