Cette espèce a une carapace presque carrée, légèrement plus large que longue, pouvant atteindre 20 mm de large. Cette carapace porte des stries parallèles principalement dans sa région antérieure. Elle ne porte qu'une seule dent en arrière de l'angle orbital externe. Les chélipèdes sont sub-égaux ; le bord coupant des doigts est muni de dents triangulaires ; l'extrémité des doigts est corné et creusé en cuiller. Les propodes des deux premières pattes ambulatoires (P2 et P3) n'ont pas de brosses de soies ; au mieux ils ont une aire dense de soies raides chez les jeunes crabes. La marge inférieure du mérus de la dernière paire de pattes ambulatoires (P5) est lisse, sans dents. Le sixième somite abdominal conjointement avec le telson est triangulaire. La carapace a des taches de couleur bleutée-grisâtre ou jaune clair sur un fond sombre, brun ou noir.
Détermination et espèces proches.
L'identification de l'espèce est relativement simple.
Biologie-éthologie.
Il y a peu de données sur la biologie de cette espèce. Elle est parasitée par la sacculine Sacculina carcini.
Écologie et distribution.
Cette espèce est principalement présente au niveau de l'eau sur les rochers battus par la houle, en particulier sur les trottoirs à Lithophyllum tortuosum. C'est une espèce médierranéenne et du proche atlantique (zone macaronésienne). L'espèce peut être impactée par la pollution marine de surface.
P. Noël(UMS 2006 Patrimoine Naturel (AFB / CNRS / MNHN)),2016
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
