Parthenina
Parthenina is a genus of very small sea snails, pyramidellid gastropod mollusks or micromollusks. This genus was previously placed in the subfamily Chrysallidinae of the family Odostomiidae. The name "Parthenia" was created by Lowe in 1840 for the species in this group, but had to be replaced since it was preoccupied by a name for a group of dipterans described by Roubineau-Desvoidy in 1830. Shell description. In the original description Bucquoy, Dautzenberg & Dollfus (1833) states (in English translation) that "Partnenina" is a type of "Odostomia" with a mesh-like surface or with longitudinal ridges. Between these ridges there  are series of spiral ridges. Many of the European species in the genus have for a long time been wrongly placed in the genus "Chrysallida", but Schander et al. (2003) showed that they should indeed be placed in the genus "Parthenina". This separation was followed by Pimenta et al. (2009) for Brazilian species. The synonymy with "Besla" Dall & Bartsch, 1904 proposed by Micali et al. (2012) is debatable. The type species of "Besla" has a protoconch axis at 90° with that of teleoconch ("type A protoconch") whereas that of "Parthenina" is tilted nearly 180° ("type C"); this important  character suggests that they are unrelated and that their teleoconch sculpture may be convergent Taxonomy. The Eastern Atlantic and Mediterranean species of the family Pyramidellidae, here listed under the genus "Parthenina" , have been included by most 20th-century European authors in the genus "Chrysallida" , following a lead by Winckworth (1932). The first explicit statement that this is incorrect was voiced by van Aartsen, Gittenberger & Goud (2000: 21) "None of the many species from European Atlantic and Mediterranean waters currently included in "Chrysallida" conforms exactly to the description of the genus sensu stricto", but they still used "Chrysallida" as a genus  and used "Parthenina" and other names as subgenera. Micali, Nofroni & Perna (2012) formally raised "Parthenina" to the rank of genus and included a number of European species, whereas other congeners not treated in that paper were still listed in WoRMS and elsewhere as "Chrysallida". Hoisaeter (2014) transferred some more species but still listed five species under "Chrysallida". The current treatment follows Giannuzzi-Savelli, Pusateri, Micali, Nofroni & Bartolini (2014) who provided a quite sensible treatment and transferred the relevant Mediterranean species to "Parthenina" and other genera, without any species retained in "Chrysallida". This scheme yet has to be tested against a  phylogenetic hypothesis based on molecular sequence data. Life history. The genus is parasitic, manly on serpulid polychaete worms. They are known to have spermatophores. Species. Species within the genus "Parthenina" include: