World Congress of Malacology Antwerp ... - Unitas Malacologica

The IUCN Red List Categories and Criteria (version 3.1) were used for classifying the Moroccan
freshwater species of the family Hydrobiidae. This preliminary assessment is applied at national level
to obtain a taxon’s risk of extinction within Morocco and proposed to be agreed with relevant Red
List Authority. Habitats of species analysed are threatened, due mainly to habitat degradation,
eutrophication and water exploitation and need protection, preservation and valorisation planning.
Discussion is intended to include information about Hydrobiid snails of the North African region to
be for IUCN red list assessment at regional level.
Giustia n.gen. (Gastropoda: Hydrobiidae) a new genus of the groundwater micromollusks of
Morocco
Ghamizi, Mohamed 1 ; Bodon, Marco 2
1. University Cadi Ayad, Muséum d’Histoire Natrurelle de Marrakech, Faculté des
Sciences Semlalia, BP 2390 Marrakech, Morocco,
Email: mghamizi@yahoo.fr
2. Via Niccolini 70/6 - 16166 Genova, Italy
The new genus Giustia is described for a new hydrobiid species. Morphological and anatomical
characters analysis confirms clearly differences from unknown freshwater valvatoid hydrobiid
genera. Ten species were formally recognized belonging to this new genus, all are micromollusks,
and stygobiont, and endemic and inhabiting restricted localities of specific groundwater systems of
Morocco. The ten species showing conchological and anatomical (especially genital tracts) characters
radiation closely related to their limited area of distribution and patterns of their isolation. Each
groundwater hydrographical system is defined by a particular group of species, isolated by natural
barriers like the old peri-rifain rift in the northern part of Morocco or by the mountains of the atlas
between the central part and the southern regions. Some species live in specific hyporheic water of
the stream and to be endemic to a special valley.
New genus of Acanthomeniidae (Mollusca: Solenogastres) from the Abyssal Angola Basin
Gil-Mansilla, Esther 1 ; Zamarro, María 1 ; García-Álvarez, Oscar 2 ; Urgorri, Victoriano 2,3
1. Unidade de Biodiversidade e Recursos Mariños. Instituto de Acuicultura,Universidade de Santiago
de Compostela, Spain
Email: iaesther@usc.es
2. Departamento de Zooloxía e Antropoloxía Física. Facultade de Bioloxía, Universidade de Santiago
de Compostela, Spain
3. Estación de Bioloxía Mariña da Graña, Rúa da Ribeira 1. 15590 Ferrol, Universidade de Santiago
de Compostela, Spain
During the DIVA 1 expedition, carried out in the year 2000 on the Abyssal Angola Basin, two
specimens belonging to a new genus of the family Acanthomeniidae (Solenogastres: Cavibelonia)
were collected. This new taxon is characterized by: presenting a thin cuticle without epidermial
papillae and with scale-shaped hollow acicular sclerites arranged on an only layer; a joint atriobuccal
cavity; having tubular foregut glandular ventral organs with a glandular mass that comes out at the
end of each duct (type A according to Salvini-Plawen, 1978 or Acanthomenia, Handl & Todt, 2005);
unpair genital orifice; lacking copulative stylets and respiratory folds; and a dorsoterminal sense
organ.
The presence of hollow acicular sclerites on the cuticle place the new genus within the order
Cavibelonia Salvini-Plawen, 1978 and includes it in the family Acanthomeniidae Salvini-Plawen,
1978 as it has a thin cuticle, hollow acicular sclerites and scale-shaped sclerites on its whole surface
as well as ventrolateral glandular organs in the shape of type A and type Acanthomenia. In spite of
the fact that the new taxon lacks a radula, it is classified within this family because of the
combination of the cuticle sclerites (hollow acicular and scale-shaped) and the type of foregut
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