| Bradybaenidae | |
|---|---|
| A live individual of Fruticicola fruticum | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Gastropoda |
| (unranked): | clade Heterobranchia clade Euthyneura |
| Superfamily: | Helicoidea |
| Family: | Bradybaenidae Pilsbry, 1934 (1898) |
| Genera | |
|
See text |
|
Bradybaenidae is a taxonomic family of medium-sized to small land snails, terrestrial pulmonate gastropod mollusks in the superfamily Helicoidea.
These snails are found mainly in Asia, with only one species occurring in Northwestern Europe: Fruticicola fruticum.
The name of the family and the genus Bradybaena is derived from the Greek words bradus (= slow) and baino (= walk), meaning "slow walker".
Molecular phylogenetic studies from 2007 showed that bradybaenids are closely related with the Camaenidae, which are currently recognized as a distinct family. In these studies both Bradybaenidae and Camaenidae are mutually polyphyletic, together forming a monophyletic group, however. This finding suggests that the distinction of both families as based essentially on the absence (Camaenidae) or presence (Bardybaenidae) of a diverticulum, is arbitrary. This anatomical structure was apparently lost (or was gained) in several groups in convergence and is therefore not suitable for the delimitation of natural groups.[1]
As a result, the Bradybaenidae being the younger taxon are likely to represent a junior synonym of the Camaenidae.
Contents |
Some genera of snails in this family create and use love darts as part of their mating behavior. The dart sac contains one to two glands. They are also defined by missing a diverticulum.
In this family, the number of haploid chromosomes lies between 26 and 30 (according to the values in this table).[2]
The following two subfamilies have been recognized in the taxonomy of Bouchet & Rocroi (2005):
Genera within the family Bradybaenidae include:
subfamily Bradybaeninae - they are defined by the presence of two divided glands with one to two accessory sacs.
tribe Aegistini
tribe Bradybaenini
tribe Euhadrini
subfamily Helicostylinae - they are defined by the presence of one gland that is being inserted without accessory sac (Tricheulota group) or with accessory sac (Helicostyla group).
The genus Monadenia Pilsbry, 1895 used to be placed in this family,[4] but it has been moved to the family Xanthonychidae.