corps trapu, massif, très convexe, entièrement noir, appendices compris. Les antennes sont très courtes, épaisses, non coudées. La tête est très courte, prolongée par un rostre court et épais. Les yeux sont surmontés d'un processus saillant. Le pronotum est transverse, très fortement sculpté, avec sa plus grande largeur au milieu, fortement rétréci en avant et en arrière. Les élytres sont arrondis, globuleux, très fortement sculptés par une alternance de crevasses et de petits tubercules peu saillants et surmontés d'un petit pinceau de poils jaunâtres très courts.
Identification :
difficile.
Confusions possibles :
B. undatus est plus grand et a les élytres rectangulaires, B. muricatus a des tubercules plus saillants et pourvus de poils longs bien visibles.
Périodes d'observation (adultes) :
mars à mai.
Biologie-éthologie :
Les larves se développent aux dépens des bulbes d'Allium sphaerocephalon. Les adultes se rencontrent sous les pierres et divers abris.
Biogéographie-écologie :
Milieux ouverts du littoral atlantique depuis le Morbihan jusqu'au sud de l'Espagne.
Références : Hoffmann A., 1950. Coléoptères Curculionides (Première Partie). Faune de France 52. Fédération Française des Sociétés de Sciences Naturelles. Paris: 486 pp.
The map presents a summary at the 10 x 10 km grid of the observation data for the species transmitted to the SINP. These data have been subjected to validation filters.
Distribution map from the Atlas of Departmental Biodiversity and Marine Sectors program
Current distribution in metropolitan France
The map presents a reference distribution layer of the species at the scale of departments and marine sectors. The presence and absence data were established by expertise within a network of partners. This reference distribution is used in the validation process of the SINP data at the INPN level.
Distribution map from the Atlas of Departmental Biodiversity and Marine Sectors program
Certain presence
Corresponds to a report on the basis of at least one observation proved within a period of 10 years (20 years for little-known invertebrates) preceding the year and no presumption of extinction since obtaining the last data nor doubt on reproductive and implemented nature of this population. For migratory species, the presence indicated concerns areas of reproduction.
Probable presence
This status is based on one or more of the following criteria:
search of species incomplete but presence of supportive environments;
ecology of the species consistent with the hypothesis of his presence;
the last reliable sighting is older than 10 years compared to the reference date, no recent specific research and no presumption of extinction from that date [vertebrates, invertebrates and plants well studied (rhopalocera, grasshoppers, dragonflies ...)] ;
the last reliable observation being older than 20 years, no recent specific research and no presumption of extinction from that date [poorly known taxa: fungus, many invertebrates...].
Probable or certain absence
This point covers the absence, more difficult by nature to demonstrate than presence. This status is based on one or more of the following criteria:
intensive but unsuccessful targeted research;
lack of adequate environments;
unobserved species while its presence is easily detected;
unlikely presence for historical or biogeographical reasons.
This status must be assigned to a department in which the presence of the species is casual.
Absence due to a proven extinction
Particular case of absence due to a proven extinction less than a half century ago (older disappearances are treated as "no probable or definite").
No information
In the state of knowledge, we can not comment on the presence or absence in the current department. This is the default status when not comprised in one of the previous categories or whenever there is doubt.
French Version
