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• Poster sessions

Anna Abraszewska (1) & Malgorzata Ozgo (2)

(1) Department of Invertebrate Zoology and Hydrobiology, University of Lodz, Banacha 12/16, 90-237 Lodz, Poland; (2) Institute of Biology, Pomeranian University, Arciszewskiego 22B, 76-200 Słupsk, Poland.

In Poland Anodonta cygnea is an endangered species with an EN category on the Red List of Threatened Animals. The main threat to this species is an ongoing destruction of river valley habitats. This study indicates possible ways of active protection of the species. We describe a population of A. cygnea inhabiting a young artificial pond (0,3 ha) originated as a peat hole excavated in 1994 and filled with ground and inundation waters. It is located in the Gulczanka Brook flood terrace and is surrounded by extensively utilized mid-forest meadows. Presently it is in a moderate recreational use. The banks of the pond are covered by reed-like vegetation. In shallower parts Ceratophyllum demersum L. abounds. The bottom is muddy with a thick layer of loose sediments.
The pond was occasionally stocked with fry of several fishes, including Abramis brama, Perca fluviatilis, and Esox lucius. The presence of unionid mussels was noted 10 years after the formation of the pond.

In 2007 A. cygnea, A. anatina and Unio pictorum were present in the pond. As no unionid mussels were found in the nearby Gulczanka Brook, the mussels in the pond most probably originate from glochidia introduced with the fish. The dominant species was A.cygnea with average densities from 3 to 65 indiv./m² (mean 20 indiv./m²). The population is in an early stage of development: mussels of the age 1-3, 4-5, and 6-7 years constituted 50%, 40%, and 10% respectively (N=263). They were accompanied only by single 8 year old individuals (0.8%).Mean length (± SD) was 120,0± 36,9 mm with range 58-200mm (N=99). Ten percent of individuals had shells longer than 160 mm, which suggests fast growing population.

This study indicates that introduction of fish infected with glochidia to water bodies appropriate for the mussels can restore or establish their populations. The pond described here was formed for other purposes than nature conservation and remains in recreational use. Viable populations of A. cygnea and other unionid mussels are an example of a successful reconciliation ecology.

Key words: Anodonta cygnea, anthropogenic water body,Western Poland, density, age and size structure

A northern relictic freshwater molluscan fauna in Guadalajara (Central Spain)

(1) Egmasa/Consejería de Medio Ambiente, c/Marruecos 33 bajo, 04009 – Almería (Spain); (2) Museo Nacional de Ciencias Naturales (CSIC), c/ José Gutiérrez Abascal 2, 28006 – Madrid (Spain).

An interesting northern relictic freshwater molluscan fauna have been found in some springs, lakes and peatbogs at the mountains of the Sierra de Ayllón (2,274 m), which is located among the provinces of Segovia, Madrid and Guadalajara in Central Spain.
The outstanding freshwater mollusc species present in this area are the bivalves Pisidium amnicum and Sphaerium corneum, and the gastropod Stagnicola palustris. Pisidium amnicum is distributed by the Palearctic and is the largest species of the genus. In the Iberian Peninsula P. amnicum presents a distribution restricted to the rivers Miño (Galicia), Arga (Navarra) and Órbigo, (León and Zamora). One new population of this bivalve has been found in the Sorbe river (Guadalajara), a little stream where the species lives among the vegetation of the sand banks. Sphaerium corneum lives also in the Sorbe river and in the submerged vegetation of the Somolinos lake. Although this bivalve have also a Palearctic distribution, it is not very common in Iberia, living in different localities of Catalonia, León and Vitoria; it has been also cited in Algarve (Portugal). Stagnicola palustris have also a wide distribution in Europe, while in the Iberian Peninsula is only known from a few localities, where is a very rare species at present. We have found it also in the Sorbe river and in the Somolinos lake.
The Sierra de Ayllón shelters also a relictic terrestrial vegetation composed by forests of Fagus sylvatica, a Central European species. This area is considered a refuge for F. sylvatica, a species that extended its distribution in Europe approximately 4,200-3,700 years BP (dated by pollen analysis from peatbogs). This post-glacial period (after Würm glaciation), characterized by the largest distribution known of F. sylvatica forests, could be also the phase of expansion of the range of the mentioned freshwater molluscan fauna in Spain.

References:
Araujo, R., 1995. Contribución a la taxonomía y biogeografía de la familia Sphaeridae (Mollusca: Bivalvia) en la península Ibérica e islas Baleares con especial referencia a la biología de Pisidium amnicum. Tesis Doctural, Universidad Complutense de Madrid, 393 pp.
Franco Múgica, F., M. García Antón, J. Maldonado Ruiz, C. Morla Juaristi & H. Sainz Ollero, 2001. Evolución de la vegetación en el sector septentrional del macizo de Ayllón (Sistema Central). Análisis polínico de la turbera de Pelagallinas. Anales Jardín Botánico de Madrid, 59 (1): 113-124.

Key words: Distribution, Pisidium, Sphaerium, Stagnicola

Balaton Limnological Research Institute of the HAS, Hungary

Key words: zebra mussel, monitor, competition, matter-energy flux, organic material, phytoplankton

(1) Egmasa/Consejería de Medio Ambiente. C./Marqués de la Ensenada 4, esc. B, 1º C y D. E-18004. Granada (Spain);(2) Egmasa/Consejería de Medio Ambiente, C./Marruecos, 33 bajo. E-04009. Almería (Spain); (3)Acuamed. C./ Albasanz, 11. E-28037. Madrid (Spain); (4) Departamento de Fisiología y Zoología. Facultad de Biología. Universidad de Sevilla. C./ Profesor García González s/n. E-41012. Sevilla (Spain); (5) Departamento de Geodiversidad y Biodiversidad. Consejería de Medio Ambiente (Junta de Andalucía). C./ Marqués de la Ensenada, 1. E-18071. Granada (Spain).

Key words: Habitat models, endangered moluscs, Andalusia, Spain

The Red book of the invertebrates of Andalusia has been recently edited (Barea-Azcón et al. cords, 2008) making up into a document that join the whole of the actualized information on endangered species of this animal group in the Autonomous Community of Andalusia.
For this work a cartography for each one of the 93 endangered molluscs species was generated. The scale of this distributions maps was the UTM (Universal Transverse Mercator) grid with a side of 10 km (hereafter plots). The study area comprise 1087 plots but only the 21,71% (n=236) contain information about the distribution of endangered molluscs. Our results, expressed in terms of a sum of the number of species per plot show clear trends in the distribution of the richness and define 6 marine hotspot (containing plots with 10 or more species) and 6 continental (freshwater and terrestrial) hotspot (containing plots with 3 or more species).
The marine hotspot areas are Cabo de Gata, Alborán island, Calahonda-Castell de Ferro, Punta de la Mona-Cerro Gordo-Maro, Calaburras-Cabo Pino and Strait of Gibraltar. The terrestrial hotspot areas are coastal landscapes the of Almería province and relates zones, coastal Betic mountains of the Granada province, lagoon and the peatbog of Padul, Baza depression, Alcornocales Natural Park and the low stretch of the Corbones river.
This results suggests further management implication, manly in terms of habitat protection, with enlargement of the protected areas net (some of the hotspots obtained are not protected area at present), but also with application in the guiding of conservation strategies at the species level.

Key words: Endangered molluscs, Red Book, distribution, conservation, management, Andalusia, Spain

(1) Egmasa/Consejería de Medio Ambiente. C./Marqués de la Ensenada 4, esc. B, 1º C y D. E-18004. Granada (Spain); (2) Egmasa/Consejería de Medio Ambiente, C./Marruecos, 33 bajo. E-04009. Almería (Spain); (3) Departamento de Geodiversidad y Biodiversidad. Consejería de Medio Ambiente (Junta de Andalucía). C./ Marqués de la Ensenada, 1. E-18071. Granada (Spain); (4) Dirección General de Gestión del Medio Natural. Consejería de Medio Ambiente. Avda. Manuel Siurot 50. E-41071. Sevilla (Spain).

The Environmental Council of the Andalusian Government recently has edited the “Red Book of the Andalusian Invertebrates” (Barea-Azcón et al. cords, 2008). This document involves the participation of 74 specialist and several scientific and conservationist societies and make up the major regional assessment of invertebrate species carried out in the Iberian Peninsula.
This assessment include marine, freshwater and terrestrial species. 93 molluscs taxa have been evaluated over a total of 394 invertebrate species under the IUCN regional criteria, constituting the second group only behind the arthropods. In total 9 orders have been included but only Caenogastropoda (n=38) and Stylommatophora (n=35) accumulate the 78,49% of the taxa. The 66,66% (n=62) of the taxa evaluated hold on the endangered categories established by the IUCN (Critically endangered, Endangered and Vulnerable), and have while the remaining 33,34% (n=31) belong to the categories of Near threatened (n=8), Least concern (n=8) and Data deficient (n=15).
Within the endangered taxa are specially outstanding the critically endangered gastropods Patella ferruginea Gmelin, 1791 (marine) and Orculella bulgarica (Hesse, 1915) (continental) but also 20 species belonging to the category of endangered and 40 taxa belonging to the category of vulnerable. In this work the main habitat occupies by the endangered species and the main problems affecting the conservation of the group are analyzed.
In Andalusia, the status of freshwater species and environments is particularly worrying, because of the aridity of large areas of this region, and the reduced level of springs, streams and rivers, that can not fight against the excessive water extraction and pollution.
Finally, some management recommendations focused under a sustainable development scope are highlighted.

Key words: Endangered molluscs, Red Book, conservation, management, Andalusia, Spain

Soumaya Ben Youssef, Sabiha Tlig-Zouari, Lotfi Rabaoui & Oum Kalthoum Ben Hassine

Ghar El Melh lagoon is a shallow water plane, located in the north-east of Tunisia, it communicates with the sea by only one channel. As a result of anthropic actions and natural disturbances (silting), the lagoon became prone to a major hydrodynamics alteration, water and sediment deterioration and a hyper-eutrophication (Moussa et al, 2005). The present study aims to characterize the impact of these various disturbances on the malacological communities of this ecosystem. Some prospections were carried out during winter 2008, within 18 stations spread in the lagoon area. A total of 20 mollusc species belonging to two classes (14 gastropods and 6 bivalves) were collected. With the exception of the azoic station S18, species richness varied from 3 to 8. It is relatively low compared to that observed by Romdhane and Ktari-Chakroun (1986) (47 species). The specific composition of this malaco-fauna was numerically dominated by tolerant and lagoon-affinity species i.e. the gastropods: Hydrobia ulvae, Rissoa ventricosa, Cerithium vulgatum, Ceriothopsis tubercularis, Neverita josephina, Hexaplex trunculus and the bivalves Scrobicularia plana and Cerastoderma glaucum. The estimated values of Shannon-Weaver (H’) and evenness (J) indices were low and matched with a highly-unbalanced community in the majority of study stations, except for those located at the proximity of communication channel (S4 and S10). This disturbance seems to reflect the impact of anthropic pressure but also the water stagnation of this ecosystem. The Correspondences Factorial Analysis (CFA) of species abundances coupled with an Ascending Hierarchical Classification (AHC) showed three separated clusters:
-The first cluster is strictly marine, it was represented by the station S4 which is located in the communication channel with the sea.
- The second one is a marine-affinity assemblage represented by the station S10 located in the lagoon, at the proximity of the channel.
- As for the third cluster, it is a lagoon-affinity group consisting of the 16 other intra-lagoon stations.
The reduced malacological diversity and bio-ecological balance disturbance of Ghar El Melh lagoon seems to be generated by the hyper-eutrophication of this ecosystem. 

Key words: Malaco-fauna, disturbance, eutrophication, Ghar El Melh Lagoon, Tunisia

Effects of chronic metal pollution on the genetic variation in slug populations (Gastropoda, Pulmonata, Arionidae) from the Basque Country

Metal contamination in the soil is a widespread problem in the world, in part as a result of mining activities. Due to the ability of terrestrial slugs to survive in highly contaminated soils and to respond to pollution in a measurable way, they have been proposed as suitable sentinel organism for the assessment of metal pollution. In this context, molecular approaches may provide valuable information on the population genetic effects of chronic pollution in slug populations. Therefore, DNA sequence variation was compared between native populations from the Basque Country inhabiting two mines with different levels of metal pollution and native populations living in nearby less polluted areas. The complete nuclear ITS1 and ITS2 and a fragment of the mitochondrial 16S, CO1 and 12S genes were studied by nucleotide sequencing and subsequent population genetic and phylogenetic analysis. ITS1 and ITS2 showed very little variation and did not differentiate between populations or groups. However, the high levels of intraspecific mtDNA polymorphism discriminated up to five groups. Yet, the current data do not allow to distinguish between eventual differentiation due to pollution effects and differentiation due to geographic isolation or distance. Therefore additional samples will have to be surveyed.

Acknowledgements: This work has been financially supported by the Basque Government through the ETORTEK BERRILUR II (IE06-179) project and a Grant to Consolidated Research Groups (Ref. GIC07/26-IT-393-07) and by Spanish Ministry of Education and Science through PACARI (PNCYT) project.

Key words: metal pollution, terrestrial slugs, population genetics, mtDNA

Spicular arrangement and morphology in some Mediterranean Chromodorids (Mollusca: Nudibranchia): Biological role and phylogenetic Significance(*)

(1) Departamento de Biología Animal y Ecología. Facultad de Ciencias. Universidad de Granada. Granada; (2) Departamento de Biología, Facultad de Ciencias del Mar y Ambientales, Universidad de Cádiz, Apdo. 40, 11510 Puerto Real, Cádiz, Spain.

key words: Spicules, biological role, phylogenetic significance, Chromodorididae, Nudibranchia.

Opisthobranchs from Morocco: Unravelling a largely unknown fauna

Key words: Atlantic Ocean, Morocco, Opisthobranchs, Diversity

Rita Coelho (1,2) & Gonçalo Calado (3,4)

The genus Pomacea, comprises two species that stand in opposite extremes, one is raised and desired, the other is considered a pest and therefore eradicated.
Pomacea canaliculata (Lamarck, 1822), native from South America was introduced in Asia around 1980 as a protein supplement for animal and human diets, but quickly lost its commercial value due to its non-selective herbivorous feeding habits. Currently is considered a major pest in rice production (Estebenet, 1995; Carlsson and Brönmark, 2006) and multiple and diverse eradication techniques are being developed as well as information programs for population to avoid its continuous spread.
Pomacea bridgesii (Reeve, 1856) as a much narrow distribution throughout the Amazon River system. This species prefers decomposed animal food or dead and rotting plants above fresh green ones (Aditya and Raut, 2001), which makes them suitable for aquariums equipped with a nice collection of water-plants. Due to their aquarium cleaning feeding habits and their attractive appearance, shape and size, the snails easily became a common aquarium product traded all over the world (Cowieet al, 2006).
Compared to existing diverse studies concerning Pomacea canaliculata, mainly due to its pest status, little is known about Pomacea bridgesii growth and longevity.
In this work we compare diverse aspects of both species history traits focusing on their reproductive biology and feeding habits.

Adele Cutignano (1) Gonçalo Calado (2), Helena Gaspar (3) Daniela Blihoghe (1) Marco Faimali (4) Guido Cimino (1) & Angelo Fontana (1)

Species belonging to Cephalaspidea from different geographical areas have been object of extensive investigation in both fields of chemical ecology and biosynthesis.  Recently we have studied the metabolic content of the Mexican species Bulla occidentalis, collected off Yucatan coasts (Gulf of Mexico). A preliminary chemical analysis of the freeze-dried material led to isolation of three linear polypropionates (1-3). NMR and MS data of 1-2 were identical to those reported for niuhinones A and B from Philinopsis speciosa (Colval et al., 1985)  even though a structure revision for 1 is proposed, while 3 was characterized as a novel compound. Considering the ability of Bulla species to produce their own chemicals (Fontana et al., 2004) , the presence of similar metabolites in the two organisms suggests the de novo origin of polypropionates in the Mexican Cephalaspidean and would confirm the prey/predator relationship between species belonging to herbivorous Bulla and carnivorous Philinopsis (Cimino et al., 1987). . Biosynthetic in vivo experiments in B. occidentalis are in due course. When assayed in settlement inhibition assay on laboratory reared cyprids of Balanus amphitrite, 1 displayed a significant antifouling activity (EC50<1ppm) but no general toxicity, never reported so far for analogous compounds.

Key words: polypropionates, structural elucidation, antifouling activity

(1) Istituto di Chimica Biomolecolare, CNR, Via Campi Flegrei 34, 80078 Pozzuoli (Na), Italy; (2) Centro de Modelação Ecológica IMAR. FCT/UNL, Quinta da Torre; 2825-114 Monte da Caparica, Portugal;(3) Instituto Nacional de Engenharia, Tecnologia e Inovação (INETI), Estrada do Paço do Lumiar, Edifício F, 1649-038 Lisboa, Portugal;(4) Istituto di Cibernetica ‘‘Eduardo Caianiello’’,CNR, Via Campi Flegrei 34, 80078 Pozzuoli (Na), Italy;† authors with equal contributions.

Most opisthobranch molluscs belonging to the family Chromodorididae accumulate defensive chemicals in exposed parts of their bodies, often stored in mantle dermal formations (= MDFs). In particular, most members of the genus Hypselodoris accumulate dietary sesquiterpenoids, often in high concentrations in the MDFs, for a re-use in chemical defence (Cimino et al. 1999; and references therein). Interestingly, many of them are conspicuous in appearance, since their body presents a background blue color, ranging marine to dark, with yellow, orange or whitish longitudinal lines or spots, depending on the species (Ortea et al. 1996). About the Mediterranean and Cantabrian Hypselodoris species, Ros (1976, 1977) argued that the aposematic circles would correspond to a Müllerian mimicry, that facilitates avoidance learning by predators. Interestingly, Hypselodoris fontandraui also shows the typical colour pattern of this group, but lacks MDFs (Wägele et al. 2006). Would this suggest a case of Batesian mimicry?
The topic has been approached here by using methods of organic chemistry, functional biology and histology. By 1H-NMR quantification we found high concentrations of the furanosesquiterpenoid 1 in the mantle border of the nudibranch. Compound 1 significantly deterred the shrimp Palaemon elegans, a generalist predator, from feeding. Finally, histology showed the presence of a zone inside the mantle border, possibly a reservoir of defensive compounds which has not been described earlier. In conclusion, by assessing a localized concentration of an unpalatable compound in the mantle border of H. fontandraui, our results strongly suggest to include this nudibranch in the Müllerian mimicry cycle together with all blue, white and yellow Hypselodoris species.

References:
Cimino G, Fontana A, Gavagnin M (1999) Current Organic Chemistry 3: 327–372.
Wägele H, Balesteros M, and Avila C (2006) Oceanography and Marine Biology: An Annual Review 44: 197-276.
Ortea J, Valdes A, Garcia-Gomez JC (1996) Avicennia (supplement 1): 1-165.
Ros, J. (1976). Oecologia Aquatica 2: 41-77.
Ros, J. (1977). Investigación y Ciencia 12: 48-60.

Dpto. Zoología y Biología Celular Animal, Facultad de Farmacia; Universidad del País Vasco; Paseo de la Universidad 7, 01006 Vitoria, Álava, Spain.

The taxonomy and the evolutionary interrelationships of the Helicoidea remain largely unresolved, indicating that lower level helicoidean taxa still require phylogenetic investigation. This is the case of the subfamilies and genera included in the Helicodontidae and Trissexodontidae [following CLECOM system (Bank 2003)]. Many authors disagree about the classification of the taxa included inside these families mostly because its taxonomy is based on shell morphology and the anatomy of the reproductive system, both aspects subjected to very different interpretations resulting in conflicting taxonomic systems. In this work we present the first comprehensive molecular phylogeny of the group based on DNA sequenciation of two mitochondrial (16S rDNA, COI) and one nuclear (ITS-I) loci. The work has been carried out on 42 specimens of the following genera: Helicodonta, Atenia, Trissexodon, Caracollina, Oestophora, Hatumia, Mastigophallus, Oestophorella, Gasullia, Suboestophora, Gasulliella and Gittenbergeria. The new sequences have been compared with those previously published by other authors for several Helicoidean taxa (Steinke et al., 2004; Manganelli et al., 2005), including Lindholmiola. Phylogenetic relationships were inferred using maximum parsimony, neighbour joining, maximum likelihood and Bayesian methods. The reconstructed phylogenies showed high values of support for more recent branches and confirmed the monophyletic status of all the genera of the two subfamilies here considered. We also present a proposal of the evolution of the stimulatory apparatus of the reproductive system based on the molecular phylogeny obtained.

Acknowledgments:This work has been financed by the Basque Country University (Projects: 1/UPV 0076.125-E-15911/2004 and GIU06/09), by the Regional Ministry of the Environment, Junta of Andalusia (“Program for conservation and sustainable snail exploitation in Andalusia) by the Ministerio de Educación y Ciencia (Project CGL2005-01966).

Key words: COI, 16SrRNA, ITS-I, Trissexodontidae, Helicodontidae.

Key words: behaviour, dispersal, land snails, population density, population structure

University of Siena, Dipartimento di Scienze Ambientali, Via P. A. Mattioli 4, 53100 Siena, Italy

Key words: Phylogeny; terrestrial snails; Tyrrhenian area

Department of Botany and Zoology, Masaryk University, Kotlářská 2, CZ-611 37 Brno, Czech Republic

Key words: Snails, plants, Western Carpathians, historical development, recent and fossil evidence

(1) Institute for Ecology, Evolution and Diversity, Biosciences, J. W. Goethe-Universität, Frankfurt am Main, Germany; (2) Institute of Biology, Centre for Scientific Research of the Slovenian Academy of Sciences and Arts, Novi trg 2, 1000 Ljubljana, Slovenia.

The Carychiidae are considered one of the three gastropod groups to have migrated to land independently of the higher pulmonate Stylommatophora (Morton 1955). Currently, two genera are attributed to the Carychiidae, Carychium and Zospeum. These two genera inhabit different ecological niches. Zospeum is strictly troglobitic and restricted to European karst habitats while Carychiium has a world-wide distribution and inhabits mesic forests, talus slopes, wooded swamps and riparian zones of stream beds.

Members of the blind hermaphroditic genus Zospeum comprise a relatively unknown and undescribed taxon.
Although various studies on their distribution have been conducted (Slapnik, 2001; Slapnik & Ozimec, 2004), studies addressing their ecology, morphology, anatomy and phylogenetic relationships are sparse or nonexistant. Due to its small size and the biospeleological prowess involved in collecting specimens, Zospeum studies truly involve more than what meets the eye.
We investigated specimens of the type species for the genus Zospeum, Z. spelaeum spelaeum (Rossmässler 1839) and Z. isselianum Pollonera 1887. Our comprehensive approach considers SEM observations to distinguish the two species using shell morphology. Histological studies underscored these observations by reconstructing the anatomy of these minute snails. Molecular systematic analyses of mitochondrial gene sequences (16S and CO1) serve to reveal the systematic designation within Carychiidae.

References:
Morton, J. E., 1955. Notes on the ecology and annual cycle of Carychium tridentatum at Box Hill. Proceedings of the Malacological Society of London, 31: 30-46.
Slapnik, R., 2001. Activity and movements of Zospeum isselianum Pollonera 1886 (Gastropoda, Pulmonata, Carychiidae) in a cave in the Kamniske-Savinjske Alps (Slovenia). Natura Croatica, 10: 153-162.
Slapnik, R. & R. Ozimec, 2004. Distribution of the genus Zospeum Bourguignat 1856 (Gastropoda, Pulmonata, Ellobiidae) in Croatia. Natura Croatia, 13: 115-135.

Key words: Zospeum , Ellobioidea, Carychiidae, troglobitic genus,

The growth of human population is connected with the process of urbanization. Patterns and promoters of species richness and composition as well as successional trends in urban habitats have been well studied mainly in plant and vertebrate ecology. By contrast, there is a lack of knowledge regarding invertebrate assemblages including land snails. We can summarize the ability of species to live under the urban conditions as: avoidance (anthropophobic species), adaptation (ubiquitous species) and exploitation (synanthropic species). All these responses we can found among the land snails.
Terrestrial snail assemblages were studied at 273 sites in three large cities of various natural and historical conditions in the Czech Republic. The main purpose of the study was to analyze whether is it possible to predict number of land snail species in urban habitats, particularly by means of variables characterizing human-made changes of the habitats. Out of 81 recorded species, 12 were scored as synanthropic and 24 as anthropophobic in order to test the hypothesis that species avoiding heavily distributed sites (i.e. anthropophobic species) could display more predictable distributions than the others, especially synanthropic species themselves. Using regression trees technique we identified the "habitat succession stage" and "distance from the city centre" as the most important predictors for explaining variation in all analysed categories of species richness (i.e. all species, synanthropic, anthropophobic, and difference between number of anthropophobic and synanthropic species). Human impact was responsible for both a significant decrease of snail species richness (especially anthropophobic) and an increase of synanthropic species richness. However, we observed a bimodal response for synanthropic species, which was caused by a synergic effect of human alternation of the habitats and their distance from the city centre. Natural and semi-natural sites were richer in synanthropic species when situated closer to the city-centre.
In conclusion, the response of local snail assemblages to urbanization can be generalized through a gradual decline of species richness. This pattern was mainly promoted by a sharp decrease of sensitive anthropophobic species and simultaneously by relatively low number of alien species.

Key words: Land snails, urban ecology, patterns of diversity, response to urbanization

Institute of Plant Protection, Department of Zoology, Wladyslawa Wegorka 20, 60-318 Poznan, Poland

Key words: slug; pest; plant protection; Arion lusitanicus

University of Szczecin, Department of General Zoology, Felczaka 3c, Szczecin 71-412, Poland

Acknowledgments: The study has been financially supported within a promoter grant N303 068 32/2367 budgeted in the years 2007-2009.

Key words: alien species, biogeography, cooling water, size-sex characterisation, Sinanodonta woodiana

Jesús D. Núñez, Maximiliano Cledón(1), Manuel Lopes-Lima (2), Jorge Machado & Marcelo A. Scelzo

Two pools of 120 pulmonated limpets Siphonaria lessoni were sampled in April 2008 at a contaminated and an uncontaminated (control) area of the northern coast of Argentina. Their shell length was measured to separate them into four size classes (4-6; 6-8; 8-10 and 10-12 mm) of 30 individuals each. The individual shell thickness was measured under stereomicroscope at the nearest 0.01 mm.
SEM (Scanning electron microscopy) observation of three individuals from each group was performed in order to compare the inter shell microstructure of individuals from both sites. Simultaneously, DES (Dispersive Energy Microanalysis) was performed to determine the elemental composition of the shells.
The One way ANOVA indicated that the population from the port present thicker shells than the population from the uncontaminated area (p<0.01) due to the presence of globular malformations at the inner surface of the shell. These malformations are the result of a increased secretion of organic matrix (increased composition of carbon, nitrogen and oxygen).
The limpets of the control area present thinner shell with regular deposition and the shell composition present a comparatively higher proportion of calcium carbonate.
The present results indicate that S. lessoni is sensible to certain pollutants. It remains to be determined, which of the reported contaminants is causing the observed malformations and its cost in terms of fitness of the affected population.

Key words: limpet; Siphonaria lessoni; shell growth; pollution

The patellid limpet Patella ferruginea is one of the two marine molluscs (together with P. candei candei from the Canary islands) included in the Spanish Catalogue of Endangered Species under the category of “Endangered (at risk of extinction)”. It is an endemic species of the southwestern Mediterranean, distributed from the Strait of Gibraltar to Cape Bone in Tunisia. From 89,000 to 108,000 adult specimens of this species have been estimated to occur at the Spanish coasts, most of them located at the Spanish territories on the north African coast. About 700 specimens have been recorded in Andalusian coasts (between Tarifa and Cabo de Gata), more than 350 in the Alboran Island, about 45,000 in Chafarinas Islands (more than 45% of the total), about 30.000 in Ceuta, and about 23.000 in Melilla. Recently, a Conservation Strategy for this species has been done, coordinated by the Spanish Ministry of the Environment and Rural and Marine Affairs, which is the first Conservation Strategy for an invertebrate in Spain.
The aim of the Strategy is to promote actions necessary to eliminate the risk of extinction of this gastropod, with the following main objectives:
1) Reduction of non natural mortality or loss of individuals.
2) Habitat preservation.
3) Increase species annual productivity.
4) Recover populations in areas where the species is scarce or has disappeared.
5) Enlarge the current area of distribution to potential suitable areas.
6) Develop basic research necessary to plan conservation measures.
7) Increase social awareness.
Two types of protection areas are proposed:
a) Critical areas, essential for the survival and recovering of the species (reproductive or recruitment areas);
b) Sensible areas (non critical, but of importance for conservation).
The main conservation guidelines are:
1)Species protection (to fulfil objective 1).
2)Habitat conservation (objective 2): measures oriented to preserve a protected area of suitable extension for the species.
3)Species management (objectives 3, 4, 5 and 6).
4)Habitat management (objectives 2 and 4): to improve or maintain habitat quality of critical or sensible areas.
5)Enlargement of distribution areas tending to link existing reproductive areas.
6)Aquaculture breeding (objectives 3, 4, 5).
7)Population monitoring.
8)Research focused on conservation (objective 6).
9)Communication, awareness and public participation.
10)Local development.
The Strategy will be applied by the concerned autonomous regions (Andalusia, Ceuta and Melilla) and the Ministry of the Environment, and Rural and Marine Affairs (Chafarinas Islands) through Recovery Plans. A National Working Group will coordinate institutional cooperation and conservation efforts among public administrations, improving human resources, legal actions and financial resources.  
The Strategy is currently pending approval by the State Commission for the Natural Heritage and Biodiversity, and will have a permanent validity up to fulfil its aim; it will be revised annually, with a detailed revision every five years.

Acknowledgements: The following authors have also contributed with information or helpful comments to the final redaction of the Strategy: R. Barba, I. Bueno del Campo, M. Calleja, J. Calvo, F. Espinosa, J. C. García Gómez, H. García Piña, J. A. González García, J. M. Guerra, B. Heredia,  F. J. Martínez Medina, J. L. Ruiz, A. Tejedor and J. Zapata.

Key words: Patella ferruginea, endangered species, national conservation strategy, Spain

Francisco Manuel da Silva Rodrigues Maia (1), Joana Maria Frias Medeiros de Pimenta (2), Carlos Miguel Miguez Barroso (3)

(1)NRB/L-IPIMAR CRIPCentro, Canal das Pirâmides, 3800 Aveiro; (2) INRB/L-IPIMAR CRIPNorte, Av.da General Norton de Matos, 4450-208 Matosinhos; (3) Departamento de Biologia, Universidade de Aveiro, 3810 Aveiro

The Ria de Aveiro, an estuarine lagoon located in the Portuguese north-west coast, is an important area of commercial exploitation of bivalves. The pullet carpet shell (Venerupis pullastra) is, from an economical point of view, among the most important species in the lagoon. However, the overfishing of this population, both by professional and illegal fishermen, has leaded to an apparent exhaustion of the stocks. Thus, there is an urgent need for the implementation of management and conservation measures. In this context, it was studied the growth of the pullet carpet shell in Ria de Aveiro. Shell morphometric and allometric studies were performed for the length/height (L/H), length/width (L/W) and weight/length (W*/L) relationships (this information could be used in fishery models and in improving fishing-gear selectivity). The age and the shell growth of V. pullastra were assessed using both surface growth rings and internal shell microgrowth patterns (by the acetate peel method). The estimated von Bertalanffy growth curves, expressed for length (Lt) and weight (Wt), were the following:

surface growth rings:         L_t = 45,5 [1-e^{-0,43(t+0,13)}]       W_t = 15,3[1-e^{-0,43(t+0,13)}]^2,97

shell microgrowth patterns: L_t = 54,3 [1-e^{-0,29(t+0,30)}]       W_t = 25,8[1-e^{-0,29(t+0,30)}]^2,97

Newly discovered oyster reefs of the Black Sea: in time for restoration?

National Institute of Marine Research and Development “Grigore Antipa”

Key words: oyster reef, Black Sea, Ostrea edulis.

Poster: Benito Muñoz Araújo

Morphometric analyses of Iberus gualtieranus (Pulmonata, Helicidae) complex

B.Muñoz, I.A.Álvarez, I. Pólo & J.M.Llorente

Universidad Complutense de Madrid, Dpto. Zoología y Antropolgía Física, C/ José Antonio Novais, 2 28040 Madrid, Spain.

The genus Iberus, Monfort 1810, is an endemic species of the half oriental part of the Iberian Peninsula with a typical mediterranean distribution.
This group of terrestrial snails shows a controversial taxonomy.
Iberus gualtieranus complex (Ejalde, 2008) is constituted by the big size genus representatives, including Iberus gualtieranus, I. carthaginensis, I. campesinus, I. alonensis, and two species not yet described (Elejalde et al., 2005 and Elejalde et al., 2008)
In order to characterize morphologically each one of these species, the collections of Hidalgo, Paz y Membiela, Ortiz de Zárate, García San Nicolás y Cobos deposited in the Natural Science Museum of Madrid have been digitalized, being a total of 536 individuals
To obtain the morphological shells’ data the methodology proposed by López Alcántara et al. (1985) has been followed.
The procedure has carry out a factorial discriminant analyses with which is obtained a discriminant function that let us differenciate each one of the groups that show significative differences.
Iberus gualtieranus e I. campesinus are discriminated of the rest of the species in most cases, meanwhile I. carthaginensis, I. alonensis, I. sp1 e I. sp2 are differenciated among them and with the rest of the species with slightly less percentages with the other species.
The discriminant function obtained seems to be a suitable method to use in the differenciation of the diverse species studied throught molecular analysis made by Elejalde et al., 2005 y Elejalde et al., 2008
Despite this, to improve the obtained results a morphometric study we are using the Fourier’s series.