Canthophorus dubius is a species of burrowing bug belonging to the family Cydnidae, subfamily Sehirinae.
Distribution This palearctic species is widespread in most of Europe, Asia and North Africa.Fauna europaea
It was found in Albania, Algeria, Austria, Belgium, Bosnia and Herzegovina, Bulgaria, Croatia, Cyprus, Czech Republic, Egypt, Finland, France, Germany, United Kingdom, Greece, Hungary, Iran, Israel, Italy, Lithuania, Republic of Moldova, Poland, Romania, Russia (in the northwest of the Caucasus), Slovakia, Slovenia, Spain, Sweden, Switzerland, Syria, Turkey, Ukraine and former Yugoslavia.Jerzy A. Lis. Burrower bugs of the Old World - a catalogue (Hemiptera: Heteroptera: Cydnidae). Genus, 1999
Habitat These burrowing bugs inhabit grasslands and open dry-warm areas, in particular lime or sand-marshes. In the Alps you can find them up to over 1000 meters above sea level.
Description
Canthophorus dubius can reach a length of and a width of .
The body of these shieldbugs is oval, black or dark blue, sometimes metallic green or bright violet. The margins to the pronotum and corium of the hemielytra are white. Antennae are black with the second segment smaller than third. The legs are black.Michael Chinery, Insectes de France et d'Europe occidentale, Paris, Flammarion, août 2012, 320 p. (), p. 72-73Révision du groupe des Cydnides de la famille des Pentatomides, 1.-13. ptie (1884) Membrane of the hemielytra is whitish and connexivum shows white bands.Halászfy Éva. A synopsis of the Heteroptera of Hungary and the neighbouring areas. I.: 1. Brachyplatidae; 2. Cydnidae. Annales Historico-Naturales Musei Nationalis Hungarici 4. évf. (Series nova) 187-195. 1953
This species is very similar to Canthophorus impressus. A certain identification requires dissection.British Bugs
Biology There is one generation per year. The overwintering occurs as an adult bug under foliage and in moss near the host plants. The mating takes place in May and June. The nymphs appear from June to August, the new generation of adults from July.Ekkehard Wachmann, Albert Melber, Jürgen Deckert: Wanzen. Band 4: Pentatomomorpha II: Pentatomoidea: Cydnidae, Thyreocoridae, Plataspidae, Acanthosomatidae, Scutelleridae, Pentatomidae. Goecke & Evers, Keltern 2008,
Adults and larvae are trophically associated with Thesium species (Thesium alpinum, Thesium linophyllon and Thesium pyrenaicum), more rarely with other plants: wormwood (Artemisia), mint (Salvia), thyme (Thymus) etc.
References