This dataset is about the mollusc samples obtained in the framework of the 2004 voyage of the RV “Italica”, under the Latitudinal Gradient Program (LGP), by deploying a fine-mesh dredge (Rauschert dredge). This collection is now part of the Italian National Antarctic Museum (MNA, Section of Genova) and is published with the aim of increasing the knowledge of the distribution of mollusc species in the Ross Sea. The dataset is also the first Italian contribution to ANTABIF based on materials stored at the MNA.

Project title: Latitudinal Gradient Program (LGP) R/V “Italica” voyage 2004 - Mollusca.

Curator and Promoter: Stefano Schiaparelli.

Personnel: Claudio Ghiglione, Maria Chiara Alvaro, Huw J. Griffiths, Katrin Linse.

Funding: This study is part of the Project 2002/8.6 (“The coastal ecosystem of Victoria Land Coast: distribution and structure along a latitudinal gradient”) and of the Project 2010/A1.10 (Barcoding of Antarctic Marine Biodiversity, BAMBi) funded by the Italian National Antarctic Research Program (PNRA). Vouchers are maintained at the Italian National Antarctic Museum (MNA), Section of Genoa.

Study area description: This dataset lists the species that have been collected by deploying for the first time a Rauschert dredge in the Ross Sea (Rehm et al. 2006). Samples were obtained during the Austral summer 2004 in the framework of the 19^th PNRA Antarctic expedition, on board the R/V “Italica”. The study area was the continental shelf along the latitudinal transect comprised between Cape Adare (~71°S) and Terra Nova Bay (~75°S) (Fig. 2). The Rauschert dredge was deployed in its ‘standard’ structure, i.e. having a mesh size of 500µm and with an opening of 0.5 m (Lörz et al. 1999). The dredge has been towed at a mean velocity of 1 knot to collect benthic samples at eighteen stations, comprised between 84 and 515m of depth. More details about sampling stations are reported in Rehm et al. (2006).

Design description: In the past decade, the Ross Sea has been the area studied by the Latitudinal Gradient Program (LGP; www.lgp.aq) which aimed at: i) understanding the complex ecosystems that exist along the Victoria Land coast; and ii) determining the effects of environmental change on these ecosystems; iii) maximising the transfer of information and ideas, by utilising joint logistic facilities. To achieve these targets, two temporally parallel research voyages took place during the Austral summer 2004: one on board the Italian R/V “Italica” and one on board the R/V “Tangaroa” (“BioRoss” voyage, TAN0402) organized, respectively, by NIWA (National Institute of Water and Atmospheric Research, Wellington) and PNRA (Antarctic National Research Project).

In the field, samples were collected by using a Rauschert dredge with a mesh size of 500μm (Lörz et al. 1999). Samples were fixed on board in precooled Ethanol in order to have material suitable for genetic studies. Sorting and classification was performed at the Italian National Antarctic Museum (MNA), Section of Genoa, where all the samples were acquired as permanent vouchers. The digital and SEM images of the mollusc species studied will be made available through the ANTABIF Antarctic Field Guide Project (http://afg.biodiversity.aq/about). The LGP contributed to the SCAR biology programme Evolution and Biodiversity in the Antarctic (EBA) and now to the SCAR programme State of the Antarctic Ecosystem (AntEco). The dataflow is illustrated in Figure 1.

General taxonomic coverage description: The present dataset focuses on the Kingdom Animalia, Phylum Mollusca and includes six molluscs classes: Gastropoda, Bivalvia, Monoplacophora, Solenogastres, Polyplacophora and Scaphopoda. In total 8, 359 specimens have been collected belonging to 161 species and corresponding to 505 species distributional records. Of these, in order of abundance, 5, 965 specimens were Gastropoda (accounting for 113 species), 1, 323 were Bivalvia (accounting for 36 species), 949 were Aplacophora (accounting for 7 species), 74 specimens were Scaphopoda (3 species), 38 were Monoplacophora (1 species) and, finally, 10 specimens were Polyplacophora (1 species). This data set represent the first large-scale survey of benthic micromolluscs for the area and provides important information about the distribution of several species which have been seldom or never recorded before in the Ross Sea. A detailed analysis of the distribution of mollusc species sampled by the Rauschert dredge as well as the illustration of all new records for the Ross Sea is in Ghiglione et al. (submitted). The number of newly reported species for the Ross Sea is compared with the available base line, i.e. the SOMBASE records, in Figure 3.

The dataset includes respectively for each class:

Kingdom: Animalia

Phylum: Mollusca

Class: Solenogastres

Family: Neomeniidae

Species: Solenogastres sp. 1, Solenogastres sp. 2, Solenogastres sp. 3, Solenogastres sp. 4, Solenogastres sp. 5, Solenogastres sp. 6, Neomenia sp. 1

Kingdom: Animalia

Phylum: Mollusca

Class: Polyplacophora

Family: Callochitonidae

Genus: Callochiton

Species: Callochiton sp. 1

Kingdom: Animalia

Phylum: Mollusca

Class: Monoplacophora

Family: Micropilinidae

Genus: Micropilina

Species: Micropilina arntzi Warén & Hain, 1992

Kingdom: Animalia

Phylum: Mollusca

Class: Gastropoda

Family: Acteonidae, Cancellaridae, Anatomidae, Margaritidae, Doridae, Eulimidae, Mangeliidae, Seguenzioidea, Calliotropidae, Capulidae, Newtoniellidae, Buccinidae, Skeneidae, Cylichnidae, Diaphanidae, Dotidae, Eatoniellidae, Zerotulidae, Lepetidae, Naticidae, Cerithiopsidae, Collonidae, Skeneidae, Mangellidae, Margaritidae, Orbitestellidae, Triviidae, Omalogyridae, Volutomitridae, Buccinidae, Philinidae, Raphitomidae, Rissoidae, Akiodorididae, Cingulopsidae, Pyramidellidae, Tjaernoeiidae, Muricidae, Mathildidae, Borsoniidae

Genus: Acteon, Admete, Aegires, Anatoma, Antimargarita, Antistreptus, Austrodoris, Bathycrinicola, Belalora, Brookula, Calliotropis, Capulus, Cerithiella, Chlanidota, Cirsonella, Cylichna, Diaphana, Doto, Eatoniella, Eumetula, Frovina, Fusceulima, Haliella, Hemiaclis, Iothia, Kerguelenatica, Krachia, Leptocollonia, Liotella, Lissotesta, Lorabela, Margarites, Melanella, Microdiscula, Newnesia, Nothoadmete, Notoficula, Omalogyra, Paradmete, Pareuthria, Philine, Pleurotomella, Powellisetia, Probuccinum, Prodoridunculus, Prosipho, Sinuber, Skenella, Streptocionella, Thjaernoeia, Toledonia, Torellia, Trilirata, Trophon, Turritellopsis, Typhlodaphne

Species: Acteon antarcticus Thiele, 1912, Admete haini Numanami, 1996, Aegires albus Thiele, 1912, Anatoma euglypta (Pelseneer, 1903), Antimargarita dulcis (E. A. Smith, 1907), Doris kerguelensis (Bergh, 1884), Bathycrinicola tumidula (Thiele, 1912), Oneopota striatula (Thiele, 1912), Bertellidae sp.1, Bertellidae sp.2, Brookula pfefferi Powell, 1951, Brookula cf. argentina Zelaya, Absalao & Pimienta, 2006, Brookula strebeli A.W.B. Powell, 1951, Calliotropis antarctica Dell, 1990, Cancellaridae sp.1, Cancellaridae sp.2, Capulus subcompressus Pelseneer, 1903, Cerithiella seymouriana (Strebel, 1908), Chlanidota signeyana A.W.B. Powell, 1951, Cirsonella extrema Thiele, 1912, Cylichna gelida (E. A. Smith, 1907), Diaphana paessleri (Strebel, 1905), Doto antarctica Eliot, 1907, Doto sp., Eatoniella aff. cana Ponder, 1983, Eatoniella cf. demissa (E. A. Smith, 1915), Eatoniella kerguelensis (E. A. Smith, 1875), Eulimidae sp.1, Eulimidae sp.2, Eulimidae sp.3, Eulimidae sp.4, Eulimidae sp.5, Eumetula dilecta (Thiele, 1912), Eumetula cf. dilecta (Thiele, 1912), Eumetula strebeli (Thiele, 1912), Frovina sp.1, Frovina sp.2, Fusceulima sp.1, Fusceulima sp.2, Gastropoda sp.1, Haliella sp.1, Hemiaclis incolorata (Thiele, 1912), Hemiaclis sp.1, Hemiaclis sp.2, Iothia emarginuloides (Philippi, 1868), Kerguelenatica delicatula (E. A. Smith, 1902), Krachia antartica (E. A. Smith, 1907), Leptocollonia innocens (Thiele, 1912), Liotella sp.1, Lissotesta macknighti (Dell, 1990), Lissotesta mammillata (Thiele, 1912), Lissotesta minutissima (E. A. Smith, 1907), Lissotesta notalis (Strebel, 1908), Lissotesta similis (Thiele, 1912), Lissotesta sp.1, Lissotesta strebeli (Thiele, 1912), Lissotesta unifilosa (Thiele, 1912), Lorabela davisi (Hedley, 1916), Margarites crebrilirulata (E. A. Smith, 1907), Margarites refulgens (E. A. Smith, 1907), Marseniopsis sp., Melanella antarctica (Strebel, 1908), Melanella convexa (E. A. Smith, 1907), Microdiscula vanhoeffeni Thiele, 1912, Naticidae sp.1, Newnesia antartica E. A. Smith, 1902, Nothoadmete cf. delicatula (E. A. Smith, 1907), Notoficula bouveti (Thiele, 1912), Omalogyra burdwoodiana Strebel, 1908, Omalogyra sp.1, Onoba egorovae Numanami, 1996, Onoba gelida (E. A. Smith, 1907), Onoba kergueleni (E. A. Smith, 1875), Onoba paucilirata (Melvill & Standen, 1912), Onoba sp.1, Onoba subantarctica wilkesiana (Hedley, 1916), Onoba turqueti (Lamy, 1905), Paradmete fragillima (Watson, 1882), Pareuthria plicatula Thiele, 1912, Philine alata Thiele, 1912, Pleurotomella deliciosa Thiele, 1912, Powellisetia deserta (E. A. Smith, 1907), Probuccinum tenerum (E. A. Smith, 1907), Prodoridunculus gaussianus Thiele, 1912, Prosipho nodosus Thiele, 1912, Antistreptus contrarius (Thiele, 1912), Prosipho glacialis Thiele, 1912, , Prosipho mundus E. A. Smith, 1915, Sinuber microstriatum Dell, 1990, Skenella paludinoides (E. A. Smith, 1902), Streptocionella pluralis Dell, 1990, Tjaernoeia michaeli Engl, 2002, Toledonia cf. perplexa Dall, 1902, Toledonia elata Thiele, 1912, Toledonia globosa Hedley, 1916, Toledonia limnaeaeformis (E. A. Smith, 1879), Toledonia major (Hedley, 1911), Toledonia palmeri Dell, 1990, Toledonia punctata Thiele, 1912, Toledonia sp.1, Toledonia sp.2, Toledonia sp.3, Toledonia striata Thiele, 1912, Torellia antarctica (Thiele, 1912), Torellia exilis (Powell, 1958), Trilirata macmurdensis (Hedley, 1911), Trilirata sexcarinata Warén & Hain, 1996, Trophon coulmanensis E. A. Smith, 1907, Trophon minutus Melvill & Standen, 1907, Turritellopsis latior Thiele, 1912, Typhlodaphne innocentia Dell, 1990, Typhlodaphne sp.1

Kingdom: Animalia

Phylum: Mollusca

Class: Bivalvia

Family: Philobryidae, Astartidae, Cuspidariidae, Cyamiidae, Carditidae, Cyclochlamydidae, Propeamussiidae, Mytilidae, Kelliidae, Limidae, Limopsidae, Philibryidae, Lyonsiidae, Montacutidae, Poromyidae, Nuculanidae, Siliculidae, Cuspidariidae, Thraciidae, Thyasiridae, Galeommatoidea, Yoldiidae

Genus: Adacnarca, Astarte, Cuspidaria, Cyamiomactra, Cyclocardia, Cyclochlamys, Cyclopecten, Dacrydium, Kellia, Limatula, Limopsis, Lissarca, Lyonsia, Montacuta, Mysella, Parathyasira, Philobrya, Poromya, Propeleda, Pseudokellya, Silicula, Subcuspidaria, Thracia, Waldo, Yoldiella

Species: Adacnarca nitens Pelseneer, 1903, Astarte longirostris d’Orbigny, 1842, Cuspidaria tenella E. A. Smith, 1907, Cuspidaria kerguelensis (E. A. Smith, 1885), Cyamiomactra laminifera (Lamy, 1906), Cyamiomactra robusta Nicol, 1964, Cyclocardia astartoides (Martens, 1878), Cyclochlamys gaussiana (Thiele, 1912), Cyclochlamys pteriola (Melvill & Standen, 1907), Dacrydium albidum Pelseneer, 1903, Kellia simulans E. A. Smith, 1907, Limatula hodgsoni (E. A. Smith, 1907), Limatula ovalis (Thiele, 1912), Limatula simillima (Thiele, 1912), Limopsis lilliei E. A. Smith, 1915, Limopsis marionensis E. A. Smith, 1885, Lissarca notorcadensis Melvill & Standen, 1907, Lyonsia arcaeformis Martens, 1885, Montacuta nimrodiana Hedley, 1911, Mysella cf. antarctica (E. A. Smith, 1907), Mysella charcoti Lamy, 1906, Mysella gibbosa (Thiele, 1912), Mysella sp.1, Philobrya sublaevis Pelseneer, 1903, Philobrya wandelensis Lamy, 1906, Philobrydae sp.1, Poromya spinosula Thiele, 1912, Propeleda longicaudata (Thiele, 1912), Pseudokellya gradate Thiele, 1912, Pseudokellya sp. juv., Silicula rouchi Lamy, 1911, Thracia meridionalis E. A. Smith, 1885, Parathyasira dearborni (Nicol, 1965), Thyasira debilis (Thiele, 1912), Waldo parasiticus (Dall, 1876), Yoldiella antarctica (Thiele, 1912)

Kingdom: Animalia

Phylum: Mollusca

Class: Scaphopoda

Family: Pulsellidae, Gadilidae

Genus: Pulsellum, Siphonodentalium

Species: Pulsellum sp. 1, Siphonodentalium dalli (Pilsbry & Sharp, 1898), Siphonodentalium sp. 1

Parent collection identifier: Italian Antarctic National Museum (Section of Genoa, Italy)

Collection name: Italica 2004 Rauschert Molluscs

Collection identifier: http://www.mna.it

Specimen preservation method: Specimens were fixed in pre-cooled Ethanol immediately after the extraction from the dredge net. In this way any thermal shock which could potentially alter the integrity of DNA was avoided. After fixation, specimens were sorted under a stereomicroscope, divided into morphospecies and stored in „Screw Thread Vials“ (National Scientific, USA). For study, some specimens per species have been dissected under the stereomicroscope and soft parts used for DNA extractions. Shells corresponding to these specimens have been dried in increasing ethanol concentrations, mounted on stubs and gold sputtered for scanning electron microscope observation. These specimens are maintained in a laboratory kiln with silica gel to prevent deterioration. All the other specimens are kept in ethanol in the collections of the Italian National Antarctic Museum.