Bivalve Cardium Research Articles

New Mediterranean Biodiversity Records (July 2016)

This contribution forms part of a series of collective articles published regularly in Mediterranean Marine Science that report on new biodiversity records from the Mediterranean basin. The current article presents 51 geographically distinct records for 21 taxa belonging to 6 Phyla, extending from the western Mediterranean to the Levantine. The new records, per country, are as follows: Spain: the cryptogenic calcareous sponge Paraleucilla magna is reported from a new location in the Alicante region. Algeria: the rare Atlanto-Mediterranean bivalve Cardium indicum is reported from Annaba. Tunisia: new distribution records for the Indo-Pacific lionfish Pterois miles from Zembra Island and Cape Bon. Italy: the ark clam Anadara transversa is reported from mussel cultures in the Gulf of Naples, while the amphipod Caprella scaura and the isopods Paracerceis sculpta and Paranthura japonica are reported as associated to the –also allochthonous–bryozoan Amathia verticillata in the Adriatic Sea; in the latter region, the cosmopolitan Atlantic tripletail Lobotes surinamensisis also reported, a rare finding for the Mediterranean. Slovenia: a new record of the non-indigenous nudibranch Polycera hedgpethi in the Adriatic. Greece: several new reports of the introduced scleractinian Oculina patagonica, the fangtooth moray Enchelycore anatina, the blunthead puffer Sphoeroides pachygaster (all Atlantic), and the lionfish Pterois miles (Indo-Pacific) suggest their ongoing establishment in the Aegean Sea; the deepest bathymetric record of the invasive alga Caulerpa cylindracea in the Mediterranean Sea is also registered in the Kyklades, at depths exceeding 70 m. Turkey: new distribution records for two non indigenous crustaceans, the blue crab Callinectes sapidus (Atlantic origin) and the moon crab Matuta victor (Indo-Pacific origin) from the Bay of Izmir and Antalya, respectively; in the latter region, the Red Sea goatfish Parupeneus forsskali, is also reported. Lebanon: an array of records of 5 alien and one native Mediterranean species is reported by citizen-scientists; the Pacific jellyfish Phyllorhiza punctata and the Indo-Pacific teleosteans Tylerius spinosissimus, Ostracion cubicus, and Lutjanus argentimaculatus are reported from the Lebanese coast, the latter notably being the second record for the species in the Mediterranean Sea since 1977; the native sand snake-eel Ophisurus serpens, rare in the eastern Mediterranean, is reported for the first time from Lebanon, this being its easternmost distribution range; finally, a substantial number of sightings of the lionfish Pterois miles further confirm the current establishment of this lessepsian species in the Levantine.

Bivalve suspension-feeding dynamics and benthic-pelagic coupling in an eutrophicated marine bay

The open exposed Laholm Bay in the Kattegat is eutrophicated through riverine input, mainly of N. The benthic macrofauna down to 10 m depth (60 km 2) is dominated by the suspension-feeding bivalves Cardium edule and Mya arenaria. To estimate the seasonal and annual consumption of seston by the suspension-feeders in Laholm Bay, we carried out three sets of observations. (1) The abundance and biomass of the macrofauna in this depth interval were assessed along eight transects. (2) The secondary production of the two bivalves was estimated over a 10-month period in two sampling squares. (3) The filtration rate of C. edule was determined in natural seawater in laboratory experiments during different seasons. The bivalves can in theory filter all of the water volume down to 10 m in 3 days and, thus, make a significant impact on the phytoplankton concentration. In our study, however, they filtered only approximately half of their potential feeding capacity, perhaps because food availability was low due to low turnover close to the bottom or due to physical disturbance. The majority of the phytoplankton is exported from the bay. Bivalve abundance, biomass, production and growth rate were moderate and generally lower than in adjacent areas to the north. In autumn, the bivalves consumed >90% of the seston in comparison with net-zooplankton consumption. An energy-flow diagram for the bivalves is presented including estimates of bivalve N excretion and biodeposition.

Genetic relations between the bivalves Cardium (Cerastoderma) edule, Cardium lamarcki and Cardium glaucum, studied by means of crossed immunoelectrophoresis

Rabbit antisera were raised against Cardium edule (L.) from the Waddensea locality, Skallingen, against Cardium lamarcki (Reeve) from the Danish locality, Dybso Fjord, and against Cardium glaucum (Bruguiere) from the French Mediterranean coast at Ile des Embiez. Allopatric and sympatric populations of C. lamarcki and C. edule from Swedish and Danish localities, and allopatric populations of C. glaucum from the Mediterranean Sea, Red Sea and Black Sea were studied by means of the described method and by starch gel electrophoresis of malate dehydrogenase (MDH). By means of crossed immuno-electrophoresis, using intermediary gels containing antibodies against one of the Cardium types and receiver gels containing antibodies against one of the others, type-specific and type-non-specific reactions were recorded. The results are compared with a similar investigation of Mytilus edulis, M. galloprovincialis and M. californianus. Based on immunological properties, it is shown that C. edule is a valid species different from the C. lamarcki/C. glaucum complex. It is further suggested that C. lamarcki and C. glaucum should still be referred to by these two names as significant genetic differences between them is revealed by this immunological study.

Comparative study of the formation and excretion of anaerobic fermentation products in bivalves and gastropods

1. 1. Marine bivalves and gastropods, freshwater bivalves and gastropods and land gastropods were studied for accumulation of lactate, alanine, aspartate, succinate and volatile fatty acids during 24 hr of anaerobiosis at 14°C. 2. 2. Lactate was the major fermentation product in land gastropods and was formed in significant amounts in the freshwater gastropod Lymnaea stagnalis and the marine bivalve Cardium edule. 3. 3. Accumulation of alanine occurred concomitantly with the conversion of aspartate to oxaloacetate in marine bivalves and gastropods. Land gastropods use other sources of NH 3 for pyruvate→alanine conversion in addition to aspartate. 4. 4. Alanine and acetate accumulation are interrelated. Freshwater animals with low free aspartate levels convert more pyruvate into acetate, than into alanine. 5. 5. All species accumulate succinate. 6. 6. Conversion of succinate to propionate within 24 hr of anaerobiosis was observed in all bivalves, but was absent in the gastropods, except Buccinum undatum. 7. 7. Many species excrete volatile fatty acids, but some species, e.g. Lymnaea stagnalis, also excrete lactate and succinate.

Recovery of Benthic Macrofauna from Chronic Pollution in the Sea Area off a Refinery Plant, Southwest Finland

Quantitative field studies (density, wet weight biomass, Shannon diversity, species richness, evenness of distribution) on benthic sublittoral macrofauna were made in the vicinity of an oil refinery in southwest Finland before and after the installation of a new wastewater treatment plant that reduced the amount of oil and liquid effluents by ca. 90–95%. The number of species and species diversity increased during the 1st and 2nd yr after pollution abatement at the stations close to the former outflows. The amphipods Pontoporeia affinis, Corophium volutator, and C. lacustre, midge larvae of the Chironomus plumosus-group, the oligochaete Tubifex costatus, the polychaetes Harmothoe sarsi and Polydora redeki, and the bivalve Cardium sp. were the most successful recolonizers of the 23 taxa sampled. The strong lethal effect of oil-contaminated sediments upon Chironomus plumosus larvae decreased markedly in laboratory experiments (LT50 was estimated at 7 d in 1973 and at 28 d in 1974; in 1975, 80–90% of the larvae survived for 28 d). Details of postabatement succession are discussed. The results demonstrate not only the recovery from chronic oil pollution but also the degree of ecological damage caused by previous continuous discharge of oil. Key words: Baltic Sea, Chironomus plumosus, macrobenthos, oil pollution, pollution abatement, recolonization, sediment biotests

Activity and heart rate of bivalve molluscs in their natural habitat.

KNOWLEDGE of the ecophysiology of intertidal molluscs is largely derived from observations of their littoral distribution and experiments carried out under laboratory conditions1. The results of a preliminary investigation of the activity and heart rate of the bivalves Cardium edule and Donax vittatus in situ in their natural habitat are presented here.

Studies on the parasites of Cardium edule L.: Cercaria fulbrighti n.sp., a Gymnophallus larva with a forked tail

A summary of the trematode parasites which have been recorded from the cockle is given.A furcocercous, Gymnophallus larva, Cercaria fulbrighti n.sp., from the marine bivalve Cardium edule L., is described from Plymouth, England. The tail of this larva may degenerate completely while the cercaria is still within the sporocyst.Simultaneous development of more than one species of cercaria has been recorded in four out of 420 specimens of C. edule L. Two double and two triple infections were found.Available evidence suggests a phylogenetic relationship between the Gymnophallus group and certain of the Furcocercous cercariae.