World Congress of Malacology Antwerp ... - Unitas Malacologica

Three new species of minute heterobranchs (Gastropoda: Heterobranchia: Omalogyridae and
Rissoellidae) from Namibia
Rolán, Emilio 1 ; Luque, Ángel A. 2 ; Peñas, Anselmo 3
1. Museo de Historia Natural, Universidad de Santiago de Compostela, Santiago de Compostela,
Spain,
Email: erolan@emiliorolan.com
2. Laboratorio de Biología Marina, Departamento de Biología, Universidad Autónoma, C/ Darwin, 2,
28049 Madrid, Spain,
Email: angel.luque@uam.es
3. Olérdola, 39, 5º C, 08800 Vilanova i la Geltrú, Barcelona, Spain,
Email: anspm1@yahoo.es
Namibian molluscan fauna is poorly known, with only about 140 species of marine molluscs
recorded up to now. The superfamilies Rissoelloidea and Omalogyroidea, currently included in
Heterobranchia, contain only the nominotypical families (Rissoellidae and Omalogyridae,
respectively), and comprise minute marine gastropods which are still scarcely known all over the
world. About 26 species of omalogyrids and 20 rissoellids have been described from the Atlantic, but
there are no records of species of these two families from Namibia.
Samples collected near Swakopmund (central Namibia) by washing algae from intertidal rocky pools
result in several living specimens of two Omalogyridae and one Rissoellidae new species, which are
here described.
Retrotortina n. sp. differs from the only other known Atlantic species of the genus (Retrotortina
fuscata Chaster, 1896, from the Mediterranean and NE. Atlantic) in having larger shell (up to 0.9
mm), less prominent abapical part, somewhat concave columellar edge and proportionally smaller
aperture. Radula, operculum and head-foot characters of this new species are described.
Ammonicera n. sp. (up to 0.67 mm) differs from the 17 known Atlantic species of this genus by its
teleoconch lacking axial sculpture, with only a faint spiral cord at both upper part and basis.
Rissoella n. sp. (up to 1.7 mm in length) differs from other congeneric species by shell and head-foot
characters; the radula and operculum are also described.
Towards a global taxonomic authority list for the Mollusca
Rosenberg, Gary
Academy of Natural Sciences, 1900 Benjamin Franklin Parkway, Philadelphia, PA 19103, USA,
Email: rosenberg@ansp.org
Much of systematist’s work is rummaging through the “graveyard” of synonymized and forgotten
names to determine whether a candidate new taxon is indeed undescribed. Therefore an authoritative
list of known taxa is essential to inventorying the world’s molluscan fauna. The authority list should
minimally include all the names by which each taxon is known and would enable linking data from
disparate sources, such as online databases of museum collections.
Despite the recognized potential for global taxonomic authority lists to accelerate discovery and
description of biodiversity, and the numerous programs and agencies calling for development of such
lists, progress on molluscan databases has slowed. There are several successful regional projects:
CLEMAM and CLECOM for Europe, Malacolog for the Western Atlantic, SOMBASE for the
Southern Ocean, the Indo-Pacific marine database, but they are not yet interlinked.
There are several impediments to going global. It is easier to get funding for regional projects than
global ones, and to attract funding one must have discrete, visible products that provide services
needed by the target audience. Each project thus has slightly different goals and practices. Various
standards exist for required elements in taxonomic databases, and complying with all simultaneously
is burdensome. Furthermore, scientists resist authority lists as impinging on taxonomic freedom.
To progress toward a global list, we must recognize that it is necessary to have a federation of
regional projects that feed into a central mechanism that supports multiple classifications. Editorial
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