Thamnurgus

from Wikipedia, the free encyclopedia
Thamnurgus
Thamnurgus varipes

Thamnurgus varipes

Systematics
Class : Insects (Insecta)
Order : Beetle (Coleoptera)
Subordination : Polyphaga
Family : Weevil (Curculionidae)
Subfamily : Bark beetle (Scolytinae)
Genre : Thamnurgus
Scientific name
Thamnurgus
Eichhoff , 1864

Thamnurgus is a genus from the subfamily of the bark beetle . Unusually for bark beetles, minieren their larvae in the stems of herbaceous plants .

features

The imaginal beetles are about 1.5 to 3.2 millimeters long. They are elongated oval, parallel-sided cylindrical shape, red-brown to black in color and shiny. The entire body is long and soft, hairy, loose, protruding white, this hair is quite inconspicuous. The antennae have a club-shaped shaft (scapus) and a five-membered flagellum, which is followed by a three-membered antennae lobe, which is beveled at the end (distal). The first limb is about as long as the four following together. The eyes are indented in the middle. The pronotum is longer than it is broad, flat arched (not hunched), rounded at the front, it is simple and uniformly dotted with a narrow, point-free center line. The long elytra are parallel to the center and are broadly rounded at the apex, their fall (the steep, backward-facing surface) can be flat or arched, sometimes it has a longitudinal impression, its side ridges are from inconspicuous to angular, the wing-cover seams are often raised . The rails of the legs are somewhat widened, they have four or five teeth and an end pin on the outer edge.

Females and males are quite similar to one another within the genus. The females are often slightly larger, they have a slightly shorter pronotum and longer elytra. The fall of the Elytres is slightly less dotted and furrowed lengthways. The species of the genus are partly outwardly very similar to each other and to other representatives of the Dryocoetini tribe , the males can be clearly distinguished by the shape of the Aedeagus .

distribution

Species of the genus live in the Mediterranean, partly north to Central Europe, in Eastern Europe, Asia Minor and the Caucasus region. Further species are given from the mountains of Central Africa and Madagascar.

Biology and way of life

Thamnurgus minieren in the stems of herbaceous perennials from different families: Spurge family , buttercup family , mint , Daisy Family , Nitrariaceae (only Peganum harmala ). Females lay eggs in a self-eaten hole or eat a passage in the pulp of the shoot axis, in which they lay eggs. The larvae continue to eat in this area, with the stem often swelling like a gall. In many species, the milky sap inside could be the basis of food. The newly transformed beetles often overwinter within the tunnels in the host plant.

The Central African species were found in tree-like species of giant lobelia ( Lobelia ) and giant ragweeds ( Senecio ) such as Senecio adnivalis (Syn .: Dendrosenecio adnivalis ).

Taxonomy, phylogeny, systematics

The genus includes ten species in the Palearctic , which, following a revision by Michail Mandelshtam and colleagues, are placed in three subgenera. Another species, Thamnurgus mairei Peyerimhoff, 1949 (specified from Morocco) and other species from Central Africa and Madagascar are poorly known.

  • Subgenus Thamnurgus Eichhoff, 1864, s. st. All types of milkweed ( Euphorbia )
    • Thamnurgus euphorbiae (sexton, 1845). Balkans, Italy (with Sicily and Sardinia), data for the Crimea are doubtful. Forming shoot galls on Euphorbia dendroides and Euphorbia wulfenii ( syn .: Euphorbia characias subsp. Wulfenii ).
    • Thamnurgus varipes Eichhoff, 1878. Central Europe, west to the Pyrenees, Poland, Ukraine, Balkans, Asia Minor. Mining in the stem of Euphorbia amygdaloides and Euphorbia characias
    • Thamnurgus characiae Rosenhauer, 1878. Western Mediterranean (France, Spain, Italy, Morocco, Algeria, Tunisia). Mining in the stem of Euphorbia characias and Euphorbia wulfenii .
  • Subgenus Macrothamnurgus Mandelshtam et al., 2012. All species of buttercups .
    • Thamnurgus delphinii (Rosenhauer, 1856). Spain, Italy (with Sicily), Greece, Algeria, Morocco, Asia Minor, Crimea, east to Turkmenistan. Gall-forming on the stems of annual field knight spurs ( Consolida ).
    • Thamnurgus petzi Reitter, 1901 (Syn .: Thamnurgus rossicus Alexeev, 1957). Austria, the Czech Republic, Hungary, Romania, southern Russia, on monkshood ( aconite ) and knight spurs ( delphinium ). Mining in the stem, this wilts above the drilling point.
  • Subgenus Parathamnurgus Mandelshtam et al., 2012
    • Thamnurgus caucasicus Reitter, 1887. Caucasus, steppes north of it (Russia, Ukraine), Crimea, west possibly to Bulgaria, in Georgia, Azerbaijan, north-east Turkey. on thistles ( Carduus , Cirsium ), very rarely on Euphorbia .
    • Thamnurgus brylinskyi Reitter, 1889. Central Asia, Caucasus (other details very doubtful). Host plant unclear.
    • Thamnurgus armeniacus Reitter, 1897. Turkey, Azerbaijan. Host plant unknown.
    • Thamnurgus pegani Eggers, 1933. Turkmenistan, Azerbaijan, Armenia, Turkey. on rue ( Peganum harmala )
    • Thamnurgus kaltenbachii (Bach, 1849). Central and Eastern Europe, south to Northern Italy and Montenegro, east to Russia. Forms stem galls on mint plants : Lamium album , also indicated on Betonica officinalis , Origanum vulgare , Teucrium scorodonia .

Individual evidence

  1. ↑ Karl E. Schedl : 91. Family Scolytidae (bark and ambrosia beetles). In: Heinz Freude, Karl Wilhelm Harde, Gustav Adolf Lohse (editor): Die Käfer Mitteleuropas. Volume 10: Bruchidae, Anthribidae, Scolytidae, Platypodidae, Curculionidae. Goecke & Evers, Krefeld 1981. ISBN 3872630296 , Thamnurgus on pages 69-70.
  2. ^ Alfred Balachowsky: Coléoptères Scolytides. Faune de France 50. Librairie de la Faculte des Sciences, Paris 1949. Gen. Thamnurgus on pages 164–172.
  3. ↑ a b M.Yu. Mandelshtam, AV Petrov, BA Korotyaev (2012): To the Knowledge of the Herbivorous Scolytid Genus Thamnurgus Eichhoff (Coleoptera, Scolytidae). Entomological Review 92 (3): 329-349.
  4. ^ Karl E. Schedl (1963): African high mountain Barkbeetles (219. Contribution to the morphology and taxonomy of the Scolytoidea). Annals and Magazine of Natural History Series 13 vol. 6: 29-32.
  5. ↑ Bjarte H. Jordal, Heiko Gebhard, Michail Y. Mandelshtam (2013): The red-listed species Thamnurgus rossicus in East Europe is a synonym of the rare Central European species, T. petzi (Curculionidae: Scolytinae). Zootaxa 3750 (1): 83-88. doi: 10.11646 / zootaxa.3750.1.6
  6. ↑ Erwin Weichselbaumer (2014): The monkshood cabbage bark beetle Thamnurgus petzi Reitter, 1901, in the Bavarian Donauauwald (Coleoptera: Scolytidae). Bulletin of Bavarian Entomologists 63 (1/2): 7–9.

Web links