Corbicula an annotated bibliography 1774 2005

Alkaline phosphatase activity in digestive diverticula, mantle and gills of brackish water Corbicula japonica and freshwater Corbicula leana were examined. Specific activities of the enzyme in every tissue of C. japonica were significantly higher than in C. leana, especially in the presence of 450 mM NaCl. Enhancement of enzyme activity by about 1.3 fold was found in the digestive diverticula of C. japonica and in the mantle of C. leana. In the presence of 450 mM choline chloride, enzyme activities of mantle and gills were vigorously enhanced (3.5 fold) while that of digestive diverticula were not enhanced as much, though the enzyme activity increased in every tissue of both species. The enzyme from mantle and gills of both clams had an optimum pH of 10.0   10.4, but the enzyme from the digestive diverticula had 2 optima, pH 8.3   8.8 and 10.0   10.8. In C. japonica, enzyme activity at higher pH optima was major, while in C. leana, the situation was reversed. In the presence of NaCl, enzyme activities were enhanced when tested at higher optimum pH, while at lower optimum pH, they were rather inhibited. Difference effects of NaCl upon alkaline phosphatase activities of digestive diverticula seemed related to the difference of relative amounts of the two isozymes in the two species.

Kado, Y. and O. Matsushima. 1976. Separation of alkaline phosphatase isozymes in digestive diverticula of brackish and fresh water clams, Corbicula japonica and Corbicula leana. Journal of Sciences of the Hiroshima University, Series B, Division 1 (Zoology) 26(2):149 157.

Two different activities of alkaline phosphatase were separated from the tissue of digestive diverticula of the brackish water clam Corbicula japonica and the freshwater clam Corbicula leana, by ammonium sulfate fractionation and identified by cellulose acetate electrophoresis. The highest activity of the 30   50% ammonium sulfate fraction, designated alkaline phosphatase A, was found at pH 8.8 in C. japonica and at pH 8.3 in C. leana, while that of 60   70% fraction, designated alkaline phosphatase B, was at pH 10.8 in C. japonica and at about pH 10.0 in C. leana. Alkaline phosphatase A activity was hardly affected by NaCl and by L phenylalanine, while that of alkaline phosphatase B was activated by about 1.4 fold in the presence of 450 mM NaCl and markedly inhibited by L phenylalanine. The activity of alkaline phosphatase A was dominant over that of alkaline phosphatase B in C. leana while the situation was reversed in C. japonica.

Kado, Y. and H. Murata. 1974. Responses of brackish and fresh water clams, Corbicula japonica and C. leana to variations in salinity. Journal of Sciences of the Hiroshima University, Series B, Division 1 (Zoology) 25:217 224.

The brackish and freshwater clams, Corbicula japonica and Corbicula leana, were acclimated to 50% sea water and fresh water and then suddenly placed in media of different salinity. The mortality and changes in chloride and water content of the soft tissues were then examined. Throughout a five day experiment in media varying from 0 to 100% sea water, it was shown that the highest tolerance to salinity without interruption of the clam's activity was about 70% sea water for C. japonica and about 15% sea water for C. leana. In both species, the tissue chloride concentration of the animal in freshwater medium was approximately equivalent to the chloride concentration of 2% sea water. Therefore, the inner chloride concentration of the two species still maintained the same hypertonicity, against outer concentrations up to 2% sea water, but, in sea water of higher concentrations, the chloride concentrations in tissues fell below that of the medium. The relationships between tissue chloride concentrations and chloride concentrations of the medium differed considerably for the two species even though no difference in the degree of dehydration could be found between the two species in various dilutions of sea water.

Kadolsky, D. 1984. Zur Taxonomie, Nomenklatur und stratigraphischen Bedeutung einiger Mollusken der Inflaten Schichten und hochsten Cerithienschten (Tertiar, Mainzer Becken). Mainzer Geowissenschaftliches Mitteilungen 13:195 203. [German with English summary]

Corbicula faujasi (Deshayes, 1830) is removed from synonymy with Polymesoda (Pseudocyrena) donacina (Sandberger, 1861) (p. 199.

Kaiser, E. 1905. Erläterung zur Geologischen Spezialkarte von Peussen. Blatt Langula (Berlin) 128:36, 45.

Kaiser, E. and E. Naumann. 1905. Erläterung zur Geologischen Spezialkarte von Peussen. Blatt Langula (Berlin) 128:55.

Kaiser, E. and E. Naumann. 1905. Über das Diluvium in Nordwest Thüringen. Jahrbuchen der Königlich Presse Geologischen Landesanstalt 1:655 656.

Kameyama, H. and S. Kitaoka. 1971. Determination of 2 aminoethyl phosphonic acid by the phenol sodium hypochlorite method. Agricultural and Biological Chemistry 35(13):2127 2129.

The ninhydrin method and the method based on the determination of P in the C P bond were unsatisfactory for the determination of 2 aminoethylphosphonic acid (2 AEP) which occurs widely in lower animals. The determination of 2 AEP by the phenol sodium hypochlorite method of Kitaoka and Nakano, is reported. Corbicula atrata shell lipids were tested.

Karatayev, A. Y., L. E. Burlakova, T. Kesterson and D. K. Padilla. 2003. Dominance of the Asiatic clam, Corbicula fluminea (Müller), in the benthic community of a reservoir. Journal of Shellfish Research 22(2):487-493.

Corbicula fluminea dominated the benthic community of Lake Nacogdoches, East Texas, composing 97% of the total biomass of benthic invertebrates. C. fluminea appears to be restricted to the littoral zone. Lower depths have lower oxygen, especially during the stratified period, which may restrict the distribution of C. fluminea. C. fluminea was found only down to a depth of 4 m and had and extremely patchy distribution. The greatest density within a patch was found at 1 m depth (35.8 ± 13.8 m^-2) and the greatest biomass within a single patch was at 2 m (137.17 ± 69.21 g times m^-2). C. fluminea density differed significantly among substrate types. The maximum density (43 ± 14 m^-2) was found in sediments with dead C. fluminea shells and course detritus, and the lowest density (3.6 ± 3.6 m m^-2) was found in silt. The spatial distributions of C. fluminea and three species of unionids were similar both in depth and across substrates in the reservoir. No correlation was found between the densities of C. fluminea and other benthic invertebrates. Finally, the effect of C. fluminea on benthic communities was contrasted to what is known about the impacts of another invasive bivalve, the zebra mussel.

Karpevich, A. F. 1975. Theory and Practice of Acclimatization of Aquatic Organisms. Pishchevaya Promyshlennost (Moskva). 432 pp. [Russian]

The introduction of Corbicula fluminea from Asian to North American waters is presented and discussed.

Kasai, A K. and A. K. Nakata. 2005. Utilization of terrestrial organic matter by the bivalve Corbicula japonica estimated from stable isotope analysis. Fisheries Science 71(1):151-158.

Kasymov, A. G. 1963. Hydrofauna of Lower Kura River and the Wingschaur Reservoir. Pakistan Academy of Azerbaijan S.S.R., Tub. House, Bachelor of Science Thesis. [Russian]

Kasymov, A. G. 1972. Freshwater Fauna of the Caucasus. Academy of Sciences of the Azerbaijan S.S.R., Institute of Zoology (Baku). 285 pp. [Russian]

The species is reported as distributed through the Caucasus, Iran, Central Asia, Afghanistan, Syria, Beludzhistan, Kashmir, and India.

Kasymov, A. G. and S. B. Gadzhiyeva. 1974. The chemical composition and caloric value of mollusks in the Mingechaur and Varvarino reservoirs. Hydrobiological Journal 10(4):38 42. [Russian with English summary]

The dry matter, organic and mineral substances, protein and lipid in molluscs of the Mingechaur and varvarino reservoirs is not the same. Corbicula fluminalis (Müller, 1774) exhibits the highest caloric value (1.11 kcal/g wet wt.) in Mingechaur Reservoir. The nutrient value of C. fluminalis is relatively low; its caloric value being little more than half that of the mollusc without the shell (2.64 as opposed to 4.84 kcal/g).

Kat, P. W. 1982. Shell dissolution as a significant cause of mortality for Corbicula fluminea (Bivalvia: Corbiculidae) inhabiting acidic waters. Malacological Review 15(1 2):129 134.

Dissolution of the shell in the umbonal region is a major source of mortality for Corbicula fluminea inhabiting acidic waters. Resistance to similar dissolution among the Unionidae may be explained in part by greater rates of compensatory nacre deposition, but seems to occur primarily because of the presence of thick conchiolin layers within the shell.

Kato, K. 1959. Melanin excretion from the Bojanus organ. Science Reports of Saitama University, Series B (Biology and Earth Sciences) 3:147 152.

Kato, K. 1960. Excretion of Kato's organ in some lamellibranchs. Science Reports of Saitama University, Series B (Biology) 3:233 244.

Kauffman, T. A. and N. K. Temnikow. 1976. Proposal for Harvesting and Utilization of the Asiatic Clam, Corbicula manilensis. California Aquaculture Co. (Unpublished Phamplet). 13 pp.

Corbicula manilensis (Philippi) has been used as a food source in the culture of the Malaysian prawn Macrobranchium sp.

Kautsky, N. and M. Kiibus. 1997. Biomass, ecology and production of benthic fauna in Lake Kariba. IN: Advances in the Ecology of Lake Kariba. University of Zimbabwe Publications, (Harare, Zimbabwe). pp. 162-182.

The distribution and biomass of the benthic fauna, surveyed in Lake Kariba in November 1984, was found to be similar to that of the vegetation. The total animal biomass of 118,840 tons dry weight, including shells, consisted of mussels (95.8%), snails (4.1%) and insect larvae (0.1%). Four species of mussels were found: Caelatura mossambicensis (von Martens) (81% of mussel biomass), Corbicula african (Krauss) (9%), Mutela dubia (Gmelin) (5%) and Aspatharia wahlbergi (Krauss) (5%). The most abundant snails were Melanoides tuberculata (Müller), Cleopatra sp. and Bellamya capillata (Frauenfeld). The biomass was high compared to that recorded in most other lakes, probably due to a lack of predator. For the colonizable 0-12 m depth interval and the total lake it was 96.2 g m^-2 including shells (15.0 g m^-2 shell-free dry weight) and 22.6 g m^-2 including shells (3.4 g m^-2 shell free dry weight), respectively. T he annual production of benthos for the 0-12 m interval was estimated at 11.0 g m^-2 yr^-1 (shell-free dry weight), and for the total lake it was 2.70 g m^-2 yr^-1 (shell-free dry weight). A multivariate direct gradient analysis showed that the abundance of various species found in Lake Kariba were correlated with environmental variables such as slope and transparency of the water. A stepwise regression analysis further showed interdependence between the gastropods Cleopatra sp., Biomphalaria pfeifferi, Lymnea natalensis, Bellanya capillata and the macrophyte Vallisneria aethiopica on one hand and between the mussel Caelatura mossambicensis and the macrophytes Lagarosiphon ilicifolius and Najas pectinata on the other hand. The average respiration, nutrient excretion and water filtration rates for mussels in Lake Kariba at 25.2^oC were estimated to about 0.6 mg O₂, 85 μg NH₄-N, 1.5 mu g PO₄-P and 0.5 l water filtered h^-1 g^-1 shell-free dry weight. This gives that a volume corresponding to the total epilimnion of the lake is filtered by the mussels annually. It was concluded that the mussels, rather than being an important food source for fish seem to play a very large role in the nutrient dynamics of Lake Kariba.

Kawabata, J. 1931. Biwakosan Gyokairu [Fishes and Shells in Lake Biwa]. Jinsendo Kawabashi Press. 98 pp.

Kawahara, T. 1965. Studies on the marine fouling communities III. Seasonal changes in the initial development of test block communities. Report of the Faculty of Fisheries of the Prefectural University of Mie 5:319 364.

Kawajiri, M. 1946. On the young of "Mashijimi", Corbicula leana. Bulletin of the Japanese Society of Scientific Fisheries 49:17 22. [Also available as ORNL tr 4588]

The larval shell of Corbicula leana Prime, a hermaphroditic bivalve, hatch out and grow in the brachia of the parent clam up to the D stage. Immediately after their discharge from the parent, the larvae become benthic. The season of discharge, though varied depending upon the water temperature, began in May in Gifu Prefecture and began in June to September in Nagano Prefecture. The discharged larvae, collected in natural waters, are rather easily raised in the laboratory at least through the first winter. The laboratory tests showed that the rate of growth does not vary much among larvae collected at four different localities in Gifu and Nagano prefectures and among those collected near Ueda City, Nagano. The size attained by the end of the year is about 1 mm shell length. This size is much smaller than that observed in Paphia philippinarum, Meretrix meretrix and Anadara subcrenata, all important commercial species cultured in shallow sea waters of Japan. Field observations indicate that a great number of the larvae die in their first winter and that some individuals that survive the first winter do not show an annulation on their umboes.

Kawanabe, H. 1978. Some biological problems. Proceedings: Congress in Denmark 1977 Internationale Vereinigung für Theoretische und Angewandte Limnologie 20(4):2674-2677.

Dendemism and differentiation of several animal and plant species is discussed, based on microfossil data of a core sample taken from Lake Biwa, Japan. Endemic organisms include differentiated in-situ, and relic species. Some fish and crustaceans belong in the differentiated in-situ category, including Cnathopegen caerulescens and Carassius cuvieri (Cyprinidae), Chaenogobius isaza (Gobiidae), and Daphnia biwaensis (Daphniidae). Relic lake species include freshwater, warm water organisms (Opsariichthys uncirostris uncirostris): freshwater cold water organisms (Valvata biwaensis); marine warm water organisms (Corbicula sandai): and marine cold water organisms (Kamaka biwae). Melosira juergensi, a marine brackish-water diatom species, is found in several parts of the core, suggesting that the lake was brackish during several interglacial ages. All Stephanodiscus diatoms abruptly change at 110 m in depth. S. carconensis and S. pusilla are found only above 110 m, whereas S. astea and S. minutula are found only below 110 m. Just at 110 m, a large volcanic ash layer 100 mm in thickness occurs. Ash-sorting indicates that eruption occurred during a rather short time; environmental factors changed greatly and most organisms were probably on the verge of extinction. At 90 and 100 m depth layers, cell diatom and green algae numbers are very small. On the contrary, production rate is high due to large amounts of chlorophyll derivatives, suggesting shallow lake conditions and submerged plant dominance.

Kayser, E. 1913. Lehrbuch der Geologie. (Berlin). II. 5. 705 pp.

Keen, A. M. 1955. A few minor pelecypod groups revised for the "Treatise of Invertebrate Paleontology". American Malacological Union Annual Report 1955:28. [Abstract]

Keen, A. M. 1971. Sea Shells of Tropical West America, Marine Mollusks from Baja California to Peru. Stanford University Press. pp. 11 12.

Keen, A. M. and R. Casey. 1969. Family Corbiculidae Gray, 1847. IN: Treatise on Invertebrate Paleontology, Part N, Mollusca 6, R. C. Moore, Ed. Geological Society of America (Boulder, Colorado). pp. 669 670.

Shells of bivalves in the Genus Corbicula are described with notes on the geologic and geographic distribution of subgenera. Subgenera of Corbicula discussed are: C. (Corbicula); C. (Corbicuella) von Ihering, 1907 [Upper Miocene, Pliocene   Pleistocene, South America]; C. (Corbiculina) Dall, 1907 [Recent, Orient]; C. (Cyanocyclas) de Blainville, 1818 [?Eocene, Pliocene   Recent, South America]; C. (Cyrenodonax) Dall, 1903 [Pleistocene   Recent, east Asia]; C. (Donacopsis) Sandberger, 1872 [Palaeocene   Eocene, Europe]; C. (Leptesthes) Meek, 1871 [Upper Cretaceous, United States]; C. (Loxotycodon) Sandberger, 1872 [Paleocene to Late Eocene, Europe]; C. (Paracorbicula) Kobayashi and Suzuki, 1939 [Late Cretaceous (Wealden), Japan]; and C. (Tellinocyclas) Dall, 1903 [Paleocene to Eocene, Europe].

Kenmuir, D. H. S. 1980. The mussel resources of Lake Kariba, Zimbabwe. Transactions of the Zimbabwe Scientific Association 60(2):7 10.

Prior to widespread sampling, the number of species present and the extent of the mussel crop in Lake Kariba were unknown. Recent research in the eastern basins of the lake showed four species (Aspartharia wahlbergi, Mutela dubia, Caelatura mossambicensis, and Corbicula africana) comprising a standing crop that could exceed 160,000 tons. Corbicula africana was found in varying densities in all areas of Lake Kariba during studies conducted in 1973.

Kenmuir, D. H. S. 1980. Seasonal breeding activity in freshwater mussels (Lamellibranchiata: Unionacea) in Lake Kariba and Lake McIlwaine, Zimbabwe. Transactions of the Zimbabwe Scientific Association 60(4):18 23.

The seasonal breeding pattern of three species of mussels in Lake Kariba and one species in Lake McIlwaine, as indicated by gravidity in females, is described. In Lake Kariba, two species (Caelatura mossambicensis and Mutela dubia) bred throughout the year, while one species (Aspatharia wahlbergi) bred in summer months only. In Lake McIlwaine, M. dubia appeared to breed for most of the year, but with possible cessation or reduction of activity in winter. It is suggested that regional differences in breeding patterns might exist. Similar studies with Corbicula leana (Fuziwara 1978) indicate temperature differences may play a significant role.

Kennard, A. S. 1944. The Crayford Brickearths. Proceedings of the Geological Association (London) 55(3):121 169.

Kennard, A. S. and B. B. Woodward. 1926. Note on F. O. (sic) Müller's types of Tellina fluminalis, fluminea, and fluviatilis. Proceedings of the Malacological Society (London) 17(1 2): 100 101.

The synonymy of Corbicula fluminalis, Corbicula fluminea, and Corbicula fluviatilis (all Müller, 1774) by Deshayes (1835) is discussed. The authors conclude that all three taxa are valid and distinct species.

Kennedy, A. J. 2003. An ecotoxicological assessment of a treated coal-mining effluent in the leading creek watershed, Meigs County, Ohio. Master of Science Thesis, Virginia Polytechnic Institute and State University (Blacksburg).

The majority of research studying the ecological impacts of the coal mining industry on freshwater systems has focused on abandoned-mined land, and the associated acid drainage and metals toxicity. Treated discharges from active mining and preparation facilities, however, can also impair lotic ecosystems through total dissolved solids (TDS) toxicity, caused primarily by the reagents used for pH modifications and the oxidation of reduced sulfur. Such impairment was best detected through application of (1) benthic macroinvertebrate surveys using metrics of biotic impairment such as relative Ephemeroptera abundance and Ephemeroptera-Plecoptera-Trichoptera (EPT) minus the tolerant caddisfly family Hydropsychidae (2) in situ growth of Corbicula fluminea during 96-d exposure and (3) laboratory testing using Ceriodaphnia dubia. Traditional metrics such as total taxa richness, EPT, diversity and biotic indices were not sensitive to elevated TDS levels. (see: http://scholar.lib.vt.edu/theses/available/etd-12192002-175616)

Kennedy, A. J., D. S. Cherry and R. J. Currie. 2003. Field and laboratory assessment of a coal processing effluent in the Leading Creek Watershed, Meigs County, Ohio. Archives of Environmental Contamination and Toxicology 44(3):324-331.

The U.S. Environmental Protection Agency has not recommended water quality criteria (WQC) to protect aquatic life from elevated sodium and sulfate concentrations, such as those associated with the coal-processing effluent of Meigs County Mine #31. This discharge, received by a tributary of the Leading Creek Watershed (SE Ohio), had a mean specific conductivity (SC) of 8,109 (7,750-8,750) 7S/cm and total metal concentrations below acute WQC. The mean 48-h LC₅₀ for Ceriodaphnia dubia in the effluent was 6,713 - 99 7S/cm; mean 48-h survival was 44% for study sites downstream of the effluent. The best indicators of impairment used in this study were Ceriodaphnia fecundity, in situ Corbicula fluminea growth, EPT minus Hydropsychidae (richness and relative abundance), and relative Ephemeroptera abundance. Mayflies, reduced by more than 99% below the effluent, were absent from all but the furthest downstream study site. SC was strongly correlated with Corbicula growth (r = m0.9755, p = 0.0009) and EPT minus Hydropsychidae richness (r = m0.8756, p < 0.0001), suggesting the effluent was primarily responsible for biotic impairment. The results indicated that SC levels, a measure of dissolved solids, in the Leading Creek Watershed that exceeded similar to 3,700 7S/cm impaired sensitive aquatic fauna.

Kennedy, V. S. 1984. Reproduction, Possible Self Fertilization, and Substrate Selection Behavior in a Population of the Introduced Asiatic Clam, Corbicula sp. in Maryland. Maryland Department of Natural Resources, Power Plant Siting Program (Annapolis). Final Report UMCEES 83 156 HEPL. 57 pp. [NTIS No. PB85 233096/XAB]

Kennedy, V. S. and J. A. Blundon. 1983. Shell strength in Corbicula sp. (Bivalvia: Corbiculidae) from the Potomac River, Maryland. The Veliger 26(1):22 25.

Forces required to crack intact shells of Corbicula sp. were determined. They are higher than those which crack the wedge clam, Rangia cuneata, a globose, strong shelled, oligohaline bivalve. Asiatic clam shell shape and strength may explain published data on crayfish predation on this animal in Oklahoma and Tennessee, in which predation was successful only on clams less than 6 mm in size or those with holes in the shell. Strong shells may also help prevent damage during periods of high river flow or strong water movement.

Kennedy, V. S., S. C. Fuller and R. A. Lutz. 1991. Shell and hinge development of young Corbicula fluminea (Müller) (Bivalvia: Corbiculoidea). American Malacological Bulletin 8(2):107-111.

Small specimens of Corbicula fluminea were collected as juveniles newly released from adults, and larger specimens were extracted from sediment taken from natural beds of adults. Lengths of the prodissoconch I averaged 196.9 ± 6.7 mu m, the average length for the prodissoconch II was 233.3 ± 5.0 μm. The dissoconch had strong commarginal sculpturing, with less prominent radial striae also present. A ligament pit occurred in the posterior region of the shell hinge. Three cardinal and two lateral teeth developed, and shell tubules were noted in the early dissoconch.

Kennedy, V. S. and L. van Heukelem. 1985. Gametogenesis and larval production in a population of the introduced Asiatic clam, Corbicula sp. (Bivalvia: Corbiculidae), in Maryland. Biological Bulletin 168(1):50 60.

Histological assessment of gametogenesis and larval production in monthly samples of Corbicula sp. collected from December 1981 to October 1983 in the Potomac River, Maryland, revealed that the clams were simultaneous hermaphrodites. Gametes of both sexes were present year round, including winter, although male reproductive tissue was less common that female tissue. Both male and female tissue were found in the smallest clam examined (9.6 mm long). Eggs and sperm were often produced in the same follicele and occurred together in the gonoducts of a number of specimens. Stereological analysis was used to quantify tissue change during the study. No clear cycles of reproductive tissue volume fractions (developing or ripe gametes) were demonstrated, suggesting that this species may be capable of responding rapidly throughout the year to suitable environmental conditions by spawning. Larvae were produced over two extended time periods, one in spring and one in fall, with the months involved varying somewhat from year to year. The smallest clam containing larvae was 13.4mm long.

Kennedy, V. S., L. Van Heukelem and W. F. Van Heukelem. 1984. Reproduction, possible self-fertilization, and substrate selection behavior in a population of the introduced Asiatic clam, Corbicula sp., in Maryland: A Final Report to Power Plant Siting Program. Prepared for Maryland Power Plant Siting Program by The Horn Point Environmental Laboratories, University of Maryland (Cambridge). 51 pp.

Kerans, B. L. and J. R. Karr. 1994. A benthic index of biotic integrity (B-IBI) for rivers of the Tennessee Valley. Ecological Applications 4(4):768-785.

Invertebrate data from rivers in the Tennessee Valley were used to: (1) evaluate the utility of 18 characteristics of invertebrate assemblages (attributes) to assess the biological condition of streams and (2) develop a comprehensive benthic invertebrate index that reflects important aspects of stream biology and responds to the effects of human society in detectable ways. Data from the Tennessee Valley Authority's (TVA) fixed-station monitoring program, established in 1986 to evaluate water resources in the Tennessee Valley, were used. The streams covered sites with various types and levels of human disturbance. TVA biologists sampled riffles and pools using quantitative methods. To evaluate attributes determinations were made of (1) the ability of each attribute to distinguish among sites (analyses of variance), (2) the associations among attributes (correlation coefficients), (3) the concordance of assessments of sites using each attribute with two independent site assessments (water quality and analysis of fish assemblages based on the index of biotic integrity), and (4) the variability of each attribute across habitats (riffles and pools) and ecoregions. Thirteen attributes (total taxa richness and taxa richnesses of intolerant snails and mussels, mayflies, caddisflies, and stoneflies; relative abundances of Corbicula, oligochaetes, omnivores, filterers, grazers, and predators; dominance; total abundance) were valuable in discriminating sites, exhibited concordance with other methods of assessment, and were relatively uncorrelated among themselves. Five attributes (sediment-surface taxa richness; relative abundances of shredders, gatherers, detritivores, and chironomids) were not acceptable for inclusion in the index because they either were not in concordance with other methods of assessment or were strongly correlated with other attributes. Based on the results of this evaluation, 13 attributes were included in a benthic index of biotic integrity (B-IBI). The B-IBI was evaluated using a more extensive fixed-station data set and was tested using an independent data set where samples were taken above and below the release of an industrial effluent to the North Fork Holston River. The fixed-station sites were correctly ranked, although rankings were not always consistent for pool and riffle habitats. B-IBI also distinguished the industrial impact. The B-IBI has potential as an assessment tool for streams, although more testing and evaluation of both the attributes and the index are warranted.

Kerans, B. L., J. R. Karr and S. A. Ahlstedt. 1991. Aquatic invertebrate assemblages: Spatial and temporal differences among sampling protocols. Journal of the North American Benthological Society 11(4):377-390.

Sampling protocols (different sampling gears used in different habitats) often vary among invertebrate studies. Three sampling protocols (replicate Hess samples taken in pools, replicate Surber samples taken in riffles, and one qualitative sample from all habitats) were examined. Differences between Hess and Surber samples probably reflect differed in organisms found in pool and riffle habitats, whereas the qualitative protocol different from the others in both habitats sampled and sampling effort. Differences among protocols for 18 attributes of invertebrate assemblages were determined using data from yearly benthic samples (1986-1989) in three Tennessee River tributaries: Clinch, Powell, and Sequatchie rivers.

Conditions differed among those rivers as reflected by fish assemblages (using the index of biotic integrity--IBI). Distinct differences were found among the protocols and many of the attributes selected for evaluation. Ten attributes either did not differ (stonefly and intolerant snail and mussel taxa richness, dominance, and proportions of omnivores, gatherers, grazers, and predators), or exhibited consistent differences (proportions of filterers, shredders, and chironomids), between riffles and pools. Of these ten attributes, six (stonefly taxa richness, dominance, and proportions of chironomids, filterers, omnivores, and predators) exhibited trends that coincided with expectations based on fish assemblage condition. Eight attributes exhibited spatial and/or temporal trends that differed between riffles and pools (total, mayfly, caddisfly, and sediment-surface taxa richness, proportions of Corbicula, detritivores, and oligochaetes, and total abundance). When interyear differences among protocols were detected, trends among sites in pools, but not riffles, matched expectations based on the biological condition of the fish assemblages (exception--the proportion of detritivores). Thus, monitoring programs may reach conclusions that are biased if biological condition is assessed with many commonly used attributes.

Kesler, D. H. 2004. Influence of a lentic area on condition indices of Corbicula fluminea in the Wolf River, Tennessee. Journal of Freshwater Ecology 19(3):445-453.

This study tested the hypothesis that filter-feeding organisms have higher condition indices downstream from a swamp than those upstream at a location not receiving lentic drainage. Sampling was performed monthly in the Wolf River in western Tennessee from February to August, 2002. Condition of the Asian clam, Corbicula fluminea (Müller), was measured as glycogen concentration, tissue percent water content, tissue dry mass:shell mass, tissue dry mass:shell cavity volume, ash-free dry mass:shell mass, and ash-free dry mass:shell cavity volume. All condition indices, except glycogen concentration, were significantly greater (P<0.05) at the downstream location but converged during the summer. Downstream individuals also had significantly heavier shells (P<0.05) for a given cavity volume. The most discriminating condition index was tissue ash-free dry mass:shell cavity volume. The higher condition of individuals immediately downstream from the swamp, compared to upstream individuals, supports the hypothesis that the swamp benefits filter-feeding organisms by exporting seston.

Keup, L., W. B. Horning and W. H. Ingram. 1963. Extension of the range of Corbicula fluminea to Cincinnati Reach of the Ohio River. The Nautilus 77(1):18 21.

Corbicula fluminea (Müller, 1774) was collected at Cincinnati, Ohio, in the Ohio River at River Mile 465.5 on 6 July 1962. It is noted that specimens were not found in samples taken fromthe river between Pittsburgh, Pennsylvania, and Moundsville, Illinois, in 1960.

Khalanski, M, F. Bergot and E. Vigneux. 1997. Consequences industrielles et ecologiques de l'introduction de nouvelles especes dans les hydrosystemes continentaux: la moule zebree et autres especes invasives [Industrial and ecological consequences of the introduction of new species in continental aquatic ecosystems: the zebra mussel and other invasive species]. Bulletin Francais de la Peche et de la Pisciculture. 1997.

Surface water is withdrawn from rivers for various industrial uses; among these, power production accounts for a large proportion. Many aquatic species settle in the raw water circuits of power plants, disrupting their operation and occasionally putting the whole plants out of use. In certain cases, the arrival of new species raises a serious problem for the industry. The introduction of two Dreissena species in the American Great Lakes, followed by their gradual spread southwards in recent years, has generated industrial damage estimated at five billion US $ per year by the turn of the century. The ecological impact of the zebra mussel in North America has been widely studied and is thought to be considerable during the phase of rapid spreading of the species. In Europe as well, the zebra mussel constitutes a threat for industrial circuits. For this reason, the species has been the object of numerous studies, particularly in France in the Seine, Rhone and Moselle rivers. Two new invasive species have recently appeared in European rivers: the Asian clam Corbicula fluminea and an amphipod: Corophium curvispinum, thus adding to the list of organisms (sponges, hydroids, bryozoans, molluscs) previously found in power plant circuits on French rivers. To ensure the availability of plant circuits, it is essential to be able to control the development of these species. This, in turn, implies in-depth knowledge of them in both biological and ecological terms. This paper presents a brief overview of present industrial methods, or methods now under study, for checking the spread of such organisms.

Khlebovich, V. V. and A. Y. Komendantov. 1985. On physiologically freshwater invertebrates of marine origin. Zhurnal Obshchei Biologii 46(3):331 335. [In Russian with English summary]

Khubka, A. N. 1979. Stratigraphic significance of Viviparus triaspolitanus (Mollusca: Vivipariade) for Quaternary deposits of Dniester Prut Interfluvium, Moldavian S.S.R., U.S.S.R. Izvestiya Akademii Nauk Modavskoi S.S.R., Seriya Biologicheskikh i Khimicheskikh Nauk 1:63 66.

Kiibus, M, and N. Kautsky. 1996. Respiration, nutrient excretion and filtration rate of tropical freshwater mussels and their contribution to production and energy flow in Lake Kariba, Zimbabwe. Hydrobiologia 331(1-3):25-32.

The productivity and ecological role of benthos in man-made Lake Kariba was assessed through the use of P/B-ratios and by measuring the metabolism (respiration, N and P excretion) of the most abundant mussel species (Aspatharia wahlbergi, Corbicula africana and Caelatura mossambicensis) in laboratory experiments. For A. wahlbergi also filtration rate was estimated. The annual production of benthos for the populated 0-12 m interval was estimated at 11.0 g m^-2 yr^-1 (shell-free dry weight) of which mussels contributed for 8.81 g (80%), snails 2.16 g (20%) and insects 0.03 g (0.3%) respectively. The most important mussel species in the lake were Caelatura mossambicensis (4.97 g m^-2 yr^-1) and Corbicula africana (3.33 g). The dominant snail species was Melanoides tuberculata (1.63 g). For the total lake, also including deeper unpopulated bottoms, the annual production of benthos was 2.70 g m^-2 yr^-1 (shell-free dry weight). Respiration and excretion varied with temperature displaying a bell-shaped relationship. Metabolic rates in Aspatharia wahlbergi increased about 5 x between 16.5^oCand the maximum at 34.0 degree C and then decreased again at 39.0 degree C, when the mussels showed signs of severe stress. Metabolism in Corbicula africana had a lower optimum with fairly constant activity between 18.6 and 29.2^oC, rapidly decreasing above this temperature. The average respiration, nutrient excretion and water filtration rates for mussels in Lake Kariba at 25.2^oC were estimated to about 0.6 mg O₂ 85 μg NH₄-N, 1.5 μg PO₄-P and 0.51 water filtered h^-1 g^-1 shellfree dry weight. This gives that a volume corresponding to about the total epilimnion of the lake is filtered by the mussels annually. Further, mussels can be estimated to remineralize 1/4 of the total load of phosphate, and 8 times the total load of nitrogen every year. The population needs 3.5 x 10⁴ tons of organic carbon for its maintenance, which indicates that about 5% of the annual phytoplankton production is channeled through mussels. It was concluded that the mussels, rather than being an important food source for fish, seem to play a large role in the nutrient dynamics of Lake Kariba.

Kil, P. 1976. An ecological study on fresh water shellfish distribution and morphological changes. Korean Journal of Zoology 19(4):189.

Kilian, C. 1925. Au Hoggar Mission de 1922. (Paris). 186 pp.

Kikuchi, T. 1964. Ecology and biological production of Lake Maka umi and adjacent regions. 3. Macro benthic communities of Lake Shinji ko and Lake Naka umi. Special Publications of the Seto Marine Biological Laboratory 2(1):21 44.

The distribution of Corbicula japonica in the benthos of lakes Shinji ko and Naka umi is presented.

Kim, J. H., H. S. Kim, I. K. Lee, J. W. Kim, H. T. Mun and K. H. Suh. 1982. Studies on the estuarine ecosystem of the Nagdong River, Korea. Proceedings of the College of Natural Sciences (Seoul) 7(2):121 164. [Korean]

The structure and function of the estuarine ecosystem of the Nagdong River were studied with special reference to analyses of environmental factors, communities of terrestrial plants on deltas and sand bars, an communities of benthic algae and invertebrates on the low tidal mudflat. The productivity of reed stands, benthic algae and phytoplankton, and the population dynamics of several invertebrates were estimated. Concentrations of soluble inorganic nutrients of water at ebb were so much greater than those at flood tide, indicating the stream provides rich nutrients. Seasonal changes of the nutrient contents did not coincide with the pattern of phytoplankton productivity, but with the amount of stream water. In the reed community on the delta, annual net production was 64.6 ton/ha/yr, leaf area index (LAI) was 10.2 and the rate of solar energy untility was 3.7% during each growing season; these were the highest values in the natural vegetation of Korea. Benthic algae (43 spp.) on the low tidal flat were identified and were distributed homogeneously. Standing crops in chlorophyll a content and in cell numbers of algae on the surface of the low tidal flat were great but varied with the different sites. The productivity of phytoplankton in the brackish water was low. Most of the 20 species of invertebrates identified on the low tidal flat were distributed homogeneously. The low rate of annual mean survival of the Corbicula japonica population, 0.13   0.24, might have resulted from fishing harvest and the predation by birds.

Kimsey, C. D. 1979. The Occurrence and Distribution of the Asiatic Clam, Corbicula, in South Carolina Estuaries. Master of Science Thesis, East Tennessee State University. vii+57 pp.

King, C. A. 1985. Laboratory Culture, Spawning, and Larval Development of Corbicula fluminea (Bivalvia: Corbiculidae). Master of Science Thesis, University of Delaware (Newark). ix + 70 pp.

Corbicula fluminea (Müller, 1774) was fed the estuarine diatom Skeletonema costatus and maintained in a recirculating laboratory system at 24 to 25^oC. Salinity varied from 0 to 8 ppt. Live weight of individual C. fluminea increased from 3% to 179% of initial weight during 4 months of laboratory culture. The animals then spawned; sperm were ejected out of the exhalant siphon and fertilized eggs were retained on the gills. The first three zygotic divisions occurred 1, 3 to 4, and 5 hrs after spawning, and trochophore larvae developed after 14 hrs. Pediveligers were released from parent clams in 4 to 5 days and metamorphosed to juveniles about 12 hrs later. Studies with fluorescent latex microspheres indicated that released larvae ingested suspended particles, but brooded larvae did not. Parental brood stock continued to grow under laboratory conditions and six months after spawning gonad smears revealed gametogenesis taking place. This is the first report of successful culture and spawning of C. fluminea in the laboratory.

King, C. A., C. J. Langdon and C. L. Counts, III. 1985. Spawning and early development of Corbicula fluminea (Bivalvia: Corbiculacea) in laboratory culture. American Malacological Bulletin 4(1):81 88.

King, R. H. and A. C. Miller. 1982. Proposed man made lotic habitat in the Tombigbee River near Columbus, MS. Journal of the Mississippi Academy of Science 27(Supplement):63. [Abstract]

A lotic habitat consisting of riffle and pool communities is being designed for and will be built in a 2.4 km long experimental section of the Tombigbee River in the vicinity of the Columbus Lock and Dam. The purpose of this study is to construct a habitat that will support higher densities and diversities of lotic invertebrates with an emphasis on the naiad mussels. An existing gravel bar in the Buttahatchie River was chosen as a prototype due to its close proximity to the experimental section and its diverse faunal communities. Many physical, chemical and biological characteristics of the Buttahatchie River were monitored during August 1981, using universally accepted limnological techniques. Seventy one taxa of invertebrates were collected during August 1981 from the gravel bar. The Insecta were the dominant macroinvertebrates with 43 species followed by the Mollusca with 19 species. The most abundant insect species were the chironomids Glyptotendipes nr. senilis, Tanytarsus querla group, and T. glabrescens group, the net spinning caddisflies Chimarra and Cheumatopsyche, and the mayfly Stenonema spp. The ubiquitous Corbicula fluminea was the most abundant bivalve with nine others considered to be common. The uncommon mussel Epioblasma penita and Pleurobema descisum were present. The proposed design of this lotic habitat is primarily based on the physical and biological characteristics of the Buttahatchie gravel bar.

Kingzett, B. and D. Tillapaugh. 1999. The shellfish culture industry in British Columbia. IN: Proceedings of the Workshop on Mussel Production Capacity (Part 2) held at Aquaculture Canada. Bulletin of the Aquaculture Association of Canada 99-3:42-44..

The three main species of shellfish cultured in British Columbia are pacific oysters Crassostrea gigas, Manila clams Corbicula manilensis and Japanese (Pacific) weathervane scallops Patinipecten caurinus. This report provides a brief overview of the British Columbia shellfish culture industry and covers current industry initiatives relating to quality assurance and the Farm Practices Protection Act, and recent discussions on industry codes of practice.

Kijviriya, V., E. S. Upatham, V. Viyanant and D. S. Woodruff. 1991. Genetic studies of Asiatic clams, Corbicula, in Thailand: Allozymes of 21 nominal species are identical. American Malacological Bulletin 8(2):97-106.

Freshwater clams of the genus Corbicula, collected from 40 sites up to 1500 km apart in Thailand, and representing 21 nominal species, show no significant geographic variation at 24 electrophoretically detected allozyme loci and are most probably all referable to the widespread Asian species, C. fluminea (Müller, 1774). Thai Corbicula have very little genetic variability. Eighty-eight percent of the samples, including one referable to Corbicula fluminea, cluster at Nei's genetic distance values of D < 0.01. Only five samples from northeast Thailand stand slightly apart from the others. Twenty nominal Thai species are synonymized according with C. fluminea; another seven nominal species are candidates for synonymy.

Kira, S., Y. Nogami, K. Taketa and H. Hayatsu. 1996. Comparison of techniques for monitoring water-borne polycyclic mutagens: efficiency of blue rayon, Sep-Pak C18, and a biota, Corbicula, in concentrating benzo(a)pyrene in a model water system. Bulletin of Environmental Contamination and Toxicology 57(2):278-83.

Kira, T. 1961. Colored Illustrations of the Shells of Japan. Hoikusha Publishing Co., Ltd. (Osaka).

The shells of Corbicula leana, Corbicula sandai, and Corbicula japonica are described and illustrated.

Klippel, W. E. and P. W. Parmalee. 1979. The naiad fauna of Lake Springfield, Illinois: an assessment after two decades. The Nautilus 94(4):189 197.

A survey of the naiad fauna of Lake Springfield during 1953 produced nine species of freshwater mussels. A second survey of the identical collection localities conducted in 1977, produced the same species. Patterned quantitative changes in the fauna were observed. Qualitative changes have resulted from the introduction of four previously unrecorded species. Of the four species established since 1953, Corbicula manilensis (Philippi) was found in the greatest frequency. It made up 28% of the total specimens recovered in the 1977 survey and was second in abundance only to Quadrula quadrula. Variations in the naiad populations have been discussed in terms of observed changes in other artificially formed lentic habitats as well as unimpounded fluvial systems.

Knowlton, F. H. 1909. The stratigraphic relations and paleontology of the "Hell Creek beds", "Ceratops beds" and equivalents, and their reference to the Fort Union Formation. Proceedings of the Washington Academy of Science 11:179 238.

Corbicula subelliptica (Meek and Hayden, 1856) is reported from the Hell Creek beds of Montana and the Laramie Cretaceous of Colorado.

Kobayashi, T. and K. T. Kurohagi. 1968. A study of the ecology of chum salmon fry, Oncorhynchus keta (Walbaum), in Abashiri Lake and its protection. Scientific Reports of the Hokkaido Salmon Hatchery 22:37 71. [Japanese with English summary]

In 1963 1966, the downstream migration of chum salmon fry was from early April to late June and the majority of fry migrated seaward after the break up of the lake ice cover. It is highly probable that the downstream migration closely relates with the low amount of food in the lake and the turbid conditions in the lake waters during ice break up. During the period from March to early May, the stomach contents of the salmon fry was small and their growth rate was very slow. From mid May to June, feeding was greater and growth rapid. The condition of the lake is changing as the water is becomming brackish. At the surface the salinity has increased about 5 times since 1927 and there is undissolved oxygen and high dissolved hydrogen sulfate below 8 m depth. The number of freshwater plankton in the lake decreased and that of the brackish or salt water increased as a result of increased salinity. The number of Chironomidae and Corbicula japonica in the lake have increased since 1936. The Chironomidae were abundant at 1 or 2m depth in the coastal area. The intercepting net set to protect the salmon fry checks the movement of the fry in the lake before the break up of the ice cover, but after the ice melts, the net shows almost no effect.

Kobayashi, T. and K. Suzuki. 1936. Non marine shells of the Jurassic Tetori series in Japan. Japanese Journal of Geology and Geography 13(1 2):35 51.

Kobayashi, T. and K. Suzuki. 1936. Non marine shells of the Haktong Wakino series. Japanese Journal of Geology and Geography 13(3 4):243 257.

Kobayashi, T. and K. Suzuki. 1939. The brackish Wealden fauna of the Yoshimo Beds in Province Nagato, Japan. Japanese Journal of Geology and Geography 16:213 224.

The brackish water fauna of the Cretaceous Wealden Yoshimo Formation of Nagato Province, Japan, is described and discussed. Paracorbicula subgen. nov. is erected with Corbicula (Paracorbicula) sanchuensis Yabe and Nagao, 1926, designated as the type species.

Kobelt, W. 1873. Nachtrage und Berichtingungen zu meinem catalog der im europaischen Faunengebiete lebenden Binnenconchylien. Malakozoologische Blätter 21:177 290.

Since the genus Corbicula is distributed throughout the entire Middle East, it must be included in the catalogue of European fauana. The European types, all belonging to the subgenus Corbicula are: Corbicula fluminalis (Müller, 1774) [Near East], Corbicula purpurea Prime [Tigris River], Corbicula saulcyi Bourguignat [Palestine], Corbicula crassula Mousson [Syria], and Corbicula consobrina Cailliaud [Nile River].

Kobelt, W. 1879. Fauna Molluscorum Extramarinorum Japoniae. Nach den von Professor Rein Gemachten Sammlungen. Abdruk a. d. Abhandlungen der Senckenbergischen Naturforschenden Gesellschaft. 171 pp.

Notes on the distribution, taxonomy, and systematics of the following species are given: Corbicula sandai Reinhardt, 1878, Corbicula straminea Reinhardt, 1878, Corbicula biformis Reinhardt, 1877, Corbicula transversa (von Martens, 1877), Corbicula pexata Prime, 1864, Corbicula martensii Clessin, 1877, Corbicula reiniana Clessin, 1879, Corbicula leana Prime, 1864, and Corbicula japonica Prime, 1864.

Kobelt, W. 1879. Fauna japonica extramarina nach den von Professor Rein gemachten Sammlungen. Abhandlungen Senckenbergischen Naturforschenden Gesellschaft 11:284  455.

See above.

Kobelt, W. 1881. Catalogue der Paläarctischen Binnenconchylien, 2nd Ed.

Kobelt, W. 1895 1897. Iconographie der Land  und Süsswasser Mollusken von Rossmässler, Fortgesetzt von Kobelt. N.F. I, Supplementband (Wiesbaden). pp. 60 68.

Kock, K. N. de and J. A. van Eeden. 1969. Die verspreiding en habitatseleksie van die Mollusca in die Mooirivier, Transvaal. Wetenskaplike Bydraes van die P. U. vir C. H. O., Reeks B: Natuurwetenskappe No. 8:1 119.

Koel, T. Mm. and K. E. Stevenson. 2002. Effects of dredge material placement on benthic macroinvertebrates of the Illinois River. Hydrobiologia 474(1-3):229-238.

Since the 1930s, dredge material has been removed from the Illinois River and placed along the main channel border in shallow depths to maintain a 2.7 m deep main channel for commercial navigation. Placement of this material changes the sediment composition from primarily silt/clay to primarily sand, and it buries pre-existing benthic invertebrates. During 1997 and 1998, the benthos of an 125 km reach of the middle Illinois River (La Grange Reach) was studied by extracting 1065 Ponar samples from randomly-selected sites which had never received dredge material, received dredge material one year previous, or received dredge material during the current year. Although total numbers of macroinvertebrates collected was lower in 1998 than in 1997, relative abundances of eight targeted taxa were highly similar between years. Chironimidae were most abundant and comprised >66% of all macroinvertebrates collected both years. Differences in densities of Chironomidae, Ephemeroptera, Sphaeriidae, Corbicula fluminea (Muller, 1774), Dreissena polymorpha (Pallas, 1771), Odonata, and Gastropoda among the three classes of dredge material placement were all significant (P< 0.05). For all taxa, densities were highest at sites that had never received dredge material; and, for all taxa except Chironimidae, densities were lowest at sites that received dredge material during the current year. No significant recovery by macroinvertebrates was noticed on dredge areas of this reach after one year (P>0.05). Future operations to maintain a channel for navigation should consider preexisting densities of macroinvertebrate taxa. Because benthic macroinvertebrates are an important component of the food web and shifting sand does not support diverse macroinvertebrate communities, strategic placement of dredge material by avoiding islands or other areas of high macroinvertebrate diversity could improve overall system productivity and biotic integrity of large river-floodplains.

Koizumi, Y., I. Nagaike and T. Inoue. 1974. Isolation and purification of amylase isozyme from Corbicula japonica. Physico Chemical Biology (Chiba) 18:201 203.

Koizumi, Y., K. Nagaike and T. Inoue. 1975. Biochemical studies of alpha amylase isozyme in the crystalline style of Corbicula japonica. Report of the Zoological Magazine 84(4):356 357.

Komaru, A. 2000. All maternal chromosomes are extruded as two polar bodies in the androgenetic clam Corbicula leana--anti-tubulin immunofluorescence. Genetics in Aquaculture VII, Townsville, Australia, 15-22 July.

Komaru, A., T. Kawagishi and K. Konishi. 1998. Cytological evidence of spontaneous androgenesis in the freshwater clam Corbicula leana Prime. Development Genes and Evolution 208(1):46-50.

Cytological observations and DNA microfluorometry of the hermaphrodite freshwater triploid clam Corbicula leana revealed unusual androgenetic development as follows: (1) the maternal genome of zygotes was extruded as two polar bodies just after karyokinesis of the first meiosis, (2) only chromosomes derived from one male pronucleus constituted the metaphase of the first cleavage of zygotes, (3) DNA content of 7-day-old veliger larvae was identical to the somatic cells of the parent. This spontaneous androgenetic process in C. leana zygotes is the first case in the phylum Mollusca and may be related to the specialized mode of reproduction; i.e. hermaphroditism and self-fertilization.

Komaru, A., K. Komaru and K. Konishi. 1999. Non-reductional spermatozoa in three shell color types of the freshwater clam Corbicula fluminea. Zoological Science 16(1):105.

Komaru, A. and K. Konishi. 1996. Ultrastructure of biflagellate spermatozoa in the freshwater clam, Corbicula leana (Prime). Invertebrate Reproduction and Development 29(3):193-197.

In contrast to "primitive" uniflagellate spermatozoa of marine and freshwater bivalves, spermatozoa of the freshwater clam, Corbicula leana (Prime) have two flagella. One flagellum (50 μm in length) originates from each of the two centrioles. The axoneme of both flagella exhibit the typical 9+2 pattern. On each side of the flagellum is a thin membranous wing which originates from the plasma membrane of the flagellum. The sperm head (17 μm in length) is elongated and tapers with a slight curve. The indistinct midpiece contains a minimum of five mitochondria and a set of centrioles. The mitochondria form a complex structure and envelop the posterior end of the nucleus like a calyx. The altered morphology of the spermatozoa from C. leana is discussed in relation to its specialized mode of reproduction, i.e. hermaphroditic with possible self-fertilization and brooding of young.

Komaru, A. and K. Konishi. 1999. Non-reductional spermatozoa in three shell color types of the freshwater clam Corbicula fluminea in Taiwan. Zoological Science 16(1):105-108.

Three distinct shell color types were found in samples of the freshwater clam Corbicula fluminea Müller collected at Hou Don, Keelung, Taiwan. DNA microfluorometric analysis revealed that these three types consisted of both diploids and triploids. DNA microfluorometry on sperm and somatic cells showed that both diploid and triploid produced non-reductional spermatozoa. These characteristics are similar to triploid C. leana Prime sampled in Japan. These findings suggest that Corbicula fluminea at different ploidy levels may be reproducing by androgenesis as already shown in C. leana from Japan.

Komaru, A., K. Konishi, K. Kawamura and H. Sakai. 1998. Morphological remarks on a Corbicula species collected in Saga Prefecture, Japan. Bulletin of National Research Institute of Aquaculture, Japan 27:37-41.

Shell morphology of freshwater Corbicula specimens collected from Saga Prefecture, southern Japan was considerably different from that of C. leana Prime. The anterior lateral teeth (ALT) of the Saga specimens is narrow in width and sharp in ridge angle while that of C. leana collected in Mie is wide and blunt: mean ratio of basal width to height of ALT was 0.69 in Mie and 1.34 in Saga specimens. General morphological feature of the Saga specimens closely resembles that of a Chinese species C. fluminea (Müller) collected from Taiwan. Further studies on such as mode of reproduction, chromosome number in Corbicula species should be required for specific identification.

Komaru, A, K. Konishi, I. Nakayama, T. Kobayashi, H. Sakai and K. Kawamura. 1997. Hermaphroditic freshwater clams in the genus Corbicula produce non-reductional spermatozoa with somatic DNA content. Biological Bulletin 193(3):320-323.

Hermaphroditic freshwater clams in the genus Corbicula produce non-reductional spermatozoa. The DNA content of spermatozoa was almost identical with that of somatic cells in C. leana from Mie Prefecture, Japan. Hermaphroditic C. aff. fluminea from Saga Prefecture and C. fluminea from Taiwan also produce non-reductional spermatozoa. On the other hand, spermatozoa of the dioecious C. sandai had half the DNA found in somatic cells. Analysis of chromosome numbers suggests that C. leana (3n = 54 in somatic cells and 18 in meiotic cells) from Mie Prefecture and C. aff. fluminea (2n = 36 in gills and 18 bivalents in meiotic cells) from Saga Prefecture are triploids and diploids, respectively. C. leana, C. aff. fluminea, and C. fluminea may lack either first or second meiosis, resulting in non-reductional spermatozoa. It is assumed that gynogenetic reproduction occurs in both species; maternal chromosomes are also nonreductional, and spermatozoa activate development of the eggs, but do not contribute to the offspring.

Komaru, A., K. Ookubo and M. Kiyomoto. 2000. All meiotic chromosomes and both centrosomes at spindle pole in the zygotes discarded as two polar bodies in clam Corbicula leana: unusual polar body formation observed by antitubulin immunofluorescence. Development Genes and Evolution 210(5):263-269.

To understand the unusual polar body formation in the androgenetic clam, Corbicula leana, whole-mount eggs stained with monoclonal antibodies against alpha-tubulin, gamma-tubulin, and 4'-6'-diamidino-2-phenylindole were examined. The meiotic spindle was located at the peripheral region of the egg at metaphase I, and its axis was parallel to the egg surface. After segregation of chromosomes at anaphase I, cytoplasmic bulges formed at both meiotic spindle pole sites. Centrosomes were located at the apical portion of the each bulge. From the apical portion of the bulge a bundle of astral microtubules radiated toward the bulge base in late anaphase resembling a half spindle. Maternal chromosomes and both centrosomes were all distributed in two first polar bodies and were eventually discarded. After the polar body formation only one male pronucleus existed in the egg cytoplasm. The present study showed that the anaphase microtubules originating from a single aster can induce the polar body formation without overlapping of microtubules from the opposing aster.

Komendantov, A. Y. 1984. Osmoregulation capacities of Corbicula japonica (Bivalvia, Corbiculidae) in waters of various salinity. Zoologicheski Zhurnal 63(5):769 771. [Russian with English summary]

Komendantov, A. Y., V. V. Khlebovich, and N. V. Aladin. 1985. Osmotic and ionic regulation in clams as the function of environmental conditions. Ekologiya 5:39 46. [Russian]

Experiments with freshwater Anodonta piscinalis Nilss., Anodonta subcircularis Clessin, brackish water Dreissena polymorpha Pallas, Corbicula japonica Prime and euryhaline marine Mya arenaria Linné, Macoma balthica balthica Linné, Macoma balthica takahokoensis Yamamoto et Habe, and Laternula limnicola Reeve indicated hyperosmoregulation in all the bivalves, exposed to low salinity exclusive of Laternula limicola. Osmoregulation and salt tolerance were found to be dependent on ambient temperature and ionic composition. It is shown that the Na⁺ concentration in the blood of the freshwater bivalves at low and high salinities remain at a higher and lower level, respectively, than in plain water.

Kong, Z.-L., L.-C. Chiang, F. Fang, F., K. Shinohara and P. Pan. 1997. Immune bioactivity in shellfish toward serum-free cultured human cell lines. Bioscience, Biotechnology, and Biochemistry 61(1):24-28.

The biologically functional effect of eight kinds of hot-water extracts of shellfish on cultured human cell lines was examined in a serum-free medium model. Meretrix lusoria and Sinonovacula constricta extracts enhanced IgM secretion of both hybridoma HB4C5 and SI102 cells when cultured with the respective extracts. The purified principle exhibited remarked activity in the adsorbed fraction in hydroxyapatite and Concanavalin A columns. The extracts of Corbicula fluminea, Crassostreas gigas, Meretrix lusoria, Anadara granosa, and Sinonovacula constricta enhanced in nitroblue tetrazolium (NBT)-reducing ability of macrophage U-M cells. Meretrix lusoria, Anadara granosa, and Sinonovacula constricta were specifically cytotoxic to both cultures of MCF-7 breast cancer cells and HuH-6KK hepatoblastoma. These findings imply that the extracts of shellfish that were examined exhibited a differential effect on immune cells and tumor cells.

Konishi, K., M. Hara, K. Kawamura, H. Furuita and A. Komaru. 1998. Morphological aspects of spermatozoa in freshwater clams of the genus Corbicula. Aquaculture '98 Book of Abstracts. p. 305.

Spermatozoa of the hermaphroditic freshwater clam, Corbicula aff. fluminea Müller from the southern part of Japan are described from light and electron microscopy. The mature spermatozoon consists of an elongated head with a rod-like acrosome, indistinct midpiece, and two long flagella with thin undulating membrane. Comparison of the sperm morphology between Corbicula species recognized two distict groups, uniflagellate and biflagellate. The uniflagellate group includes C. sandai Reinhardt and C. japonica Prime which are sexually dioecious and have a nonbrooding habit in development. The biflagellate group contains C. ieana Prime, C. fluminea Müller and the present species which are hermaphrodite and have a brooding habit. In the biflagellate group, the spermatozoa of C. leana and C. aff. fluminea were distinguished by their size and the number of mitochondria. Comparison with spermatozoa of other freshwater and marine bivalves shows various primitive and modified types. In freshwater bivalves, it has been suggested that the presence or absence of acrosomal structures can be correlated with the brooding of developing young. The spermatozoa of Corbicula species, however, have prominent acrosomes although the developmental style is different even in the same genus: i.e., C. leana broods the larvae while C. sandai releases eggs to the surrounding water. This suggests that the presence or absence of acrosomes in freshwater bivalves might not be directly related with the developmental style.

Konishi, K., K. Kawamura, H. Furuita and A. Komaru. 1998. Spermatogenesis of the freshwater clam Corbicula aff. fluminea Müller (Bivalvia: Corbiculidae). Journal of Shellfish Research 17(1):185-189.

Spermatogenesis of the hermaphrodite freshwater clam, Corbicula aff. fluminea Müller was described from light and electron microscopy. During the spermatogenetic process, difference between primary and secondary spermatocytes was hardly recognized. Mature spermatozoon consists of an elongated head (13.9 ± 0.32 μm in length) with a rod-like acrosome, indistinct midpiece, and two long flagella, 2.5 times as long as the head, each flagellum with a very thin undulating membrane. Comparison of the sperm morphology in Corbicula species presents two major groups, uniflagellated and biflagellated. Spermatozoa of C. leana and C. aff. fluminea, in spite of their close similarity, were distinguished by their size and number of mitochondria.

Kool, S. P., C. C. Coney, D. H. Stansbery and A. E. Bogan. 1981. Fresh water mollusks of the Little Pee Dee River in South Carolina. Bulletin of the South Carolina Academy of Science 43:93. [Abstract]

New records of freshwater molluscan species in the Little Pee Dee River, a tributary of the Great Pee Dee River, South Carolina, are presented. Molluscan faunal lists for the Pee Dee River system do not include any records for the Little Pee Dee River, which has apparently never been researched for Mollusca. Mollusca that can be found in the Little Pee Dee River are: Elliptio lanceolata   complex form E. fischeriana (Lea, 1838), Elliptio icterina (Conrad, 1834)   species complex, Elliptio raveneli (Conrad, 1834)   species complex, Uniomerus obesus (Lea, 1831), Corbicula leana Prime, 1864, Viviparidae   cf. Campeloma sp. and Ancylidae   cf. Laevapex sp.

Kormos, T. 1910. Uj adatok a balatonmelleki also pleiztocen retegek geologiajahoz es faunajahoz. [Neue Beitrage zur Geologie und Fauna der unteren Pleistocänschichten in der Umgebung des Balotonses]. Resultes Wissenschaftliche Erforschung des Balatonsees I(1). Tiel. Paleont. Anhang. (Budapest). pp. 42 44.

Kormos, T. 1910. Les preuves faustiniques de changements de climat de l'époque pleistocène et post pleistocène en Hongrie. Die Verànderungen des Klimas seit dem Maximum der letzten Eiszeit (Stockholm). pp. 130, 132.

Kornijow, R., J. A. Szczerbowski, T. Krzywosz and R. Bartel. 2001. The macrozoobenthos of the Iraqi lakes Tharthar, Habbaniya and Razzazah.. Archiwum Rybactwa Polskiego/ Archives of Polish Fisheries, Olsztyn 9(1):127-145. [English with Polish summary]

The Polish studies undertaken to evaluate benthic macrofauna as a fish food source were carried out monthly from March 1982 to February 1983. The total number of taxa of various taxonomic ranks found in the Iraqi lakes was 40 in Tharthar, 33 in Habbaniya and 13 in Razzazah. Chironomid larvae, oligochaetes and molluscs were the most numerous components of the zoobenthos. The most abundance chironomids inpermanently flooded areas belonged to the genera Limnochironomus, Tanytarsus, Cryptochironomus and Chironomus in Lake Tharthar, to Lauterborniella, Cryptochironomus, Chironomus and Tanypus in lake Habbaniya, and to Chironomus in Lake Razzazah. Oligochaeta consisted mainly of Limnodrilus hoffmeisteri in lakes Tharthar and Habbaniya and of Paranais in Lake Razzazah. Mollusks were predominated by Corbicula fluminea in lakes Tharthar and Habbaniya, and by Potamopyrgus antipodarum and Melanoides tuberculata in Lake Razzazah. The maximum biomass was found in the following sediments layers: 3-6 cm in Tharthar, 10-15 cm in Habbaniya, 0-1 cm in Razzazah. Patterns of seasonal changes in biomass were similar in each of the lakes studied; the maximum occurred during winter and spring and the minimum in summer. Analyses of the zoobenthos suggest that the most suitable condition for foraging by benthivorous fish in the lakes were in Razzazah, followed by Habbaniya and Tharthar.

Korniushin, A. V. 2004. A revision of some Asian and African freshwater clams assigned to Corbicula fluminalis (Müller, 1774) (Mollusca: Bivalvia: Corbiculidae), with a review of anatomical characters and reproductive features based on museum collections. Hydrobiologia 529(1):255-270.

A study of museum specimens of the genus Corbicula from the western Asiatic part of its range (Middle East, the Caucasus and Central Asia) has provided the following diagnostic anatomical characters for Corbicula fluminalis (Müller, 1774): siphons narrow with circular apertures; siphonal papillae rather scarce: about 40 around inhalant siphon (one or two rows) and 12-20 around exhalant siphon (one incomplete row); ring of dark pigment usually present internally at base of each siphon; papillae of fused mantle lobes and free mantle edge numerous, the first organized in one or two rows; radial muscles of mantle edge well developed and arranged in bands. Presence of hermaphroditic specimens, biflagellate type of spermatozoa indicating lonality, and incubation of D-shaped 190-217 μm long larvae in gills were also shown for this taxon. Two conchologically different morphotypes referred to in literature as C. fluminalis s. str. and C. purpurea (Prime, 1864) show also slight differences in size of spermatozoa and may represent different clonal lineages. The lots from North Africa possess the same characters as one of the Asian morphotypes, thus taxonomic distinctness of C. fluminalis consobrina (Cailliaud, 1827) is not supported. In contrast, C. africana (Krauss, 1848) distributed in Lake Malawi and South Africa and treated in some modern reviews as another subspecies of C. fluminalis differs by the patterns of shell sculpture, the lower number of siphonal papillae, the absence of pigmentation on the siphons and their papillae, and the size of spermatozoa; its distinctness is therefore supported, but close affinity to C. fluminalis needs confirmation. All studied African morphotypes are identical in their mode of reproduction. The new data on the anatomy and reproduction of C. fluminalis show strong similarities between this taxon and the `eastern' incubating species C. fluminea (Müller, 1774), but these taxa can be distinguished by their shell characters. The Chinese estuarine non-incubating Corbicula earlier assigned to C. fluminalis shows different anatomical and reproductive characters and is re-considered as C.cf. japonica (Prime, 1864). These results are discussed in the framework of Corbicula phylogeny based on molecular characters.

Korniushin, A. V. and M. Glaubrecht. 2003. Novel reproductive modes in freshwater clams: brooding and larval morphology in Southeast Asian taxa of Corbicula (Mollusca, Bivalvia, Corbiculidae). Acta Zoologica, Stockholm 84(4):293-315.

While the majority of marine bivalves are oviparous, the two freshwater families among the order Veneroida, i.e. Corbiculidae and Sphaeriidae, comprise species with ovoviviparous and viviparous reproduction. Within the Corbiculidae, the genus Corbicula, which is well-known for its invasive and, thus, ecologically important representatives, is characterized by (i) a wide range of limnic habitats, inhabiting both brackish water and freshwater environments, and (ii) contrasting modes of reproduction, including `planktonic' development via a freeswimming larva vs. intrabranchial incubation (brooding) of shelled juveniles. This investigation of five species of Corbicula, from the Indonesian islands Sumatra and Sulawesi, which were hitherto not studied anatomically, adds to the diversity in reproductive patterns in this genus. As a unique feature among Corbicula, we here report on two newly observed modes of brooding in species endemic to Sulawesi, (i) tetragenous brooding (i.e. in both demibranchs) in Corbicula possoensis, Sarasin, 1898 from Lake Poso, and (ii) prolonged incubation in the maternal gills, with juvenile shells reaching up to 1.3 mm in length and with a well-developed hinge in C. linduensis Bollinger, 1914 from the Lindu River system. In contrast, a third method is seen in the following taxa that incubate their young in their inner demibranchs only until the stage of juveniles with straight-hinged shells (D-shaped): C. matannensis Sarasin, 1898 from Lake Matano and Lake Mahalona, C. loehensis Kruimel, 1913 from Lake Masapi (all on Sulawesi) and C. moltkiana Prime, 1878 from Lakes Maninjau and Singkarak (on Sumatra). Details of the anatomical and histological features of ctenidia are described for each type of brooding, and some trends in the evolution of reproductive strategies within the Corbiculidae are discussed, comparing them with those known from other limnic molluscs.

Kraemer, L. R. 1976. An evaluation of the effects of dredging within the Arkansas River navigation system, V. IV. The effects upon the benthic associations. Arkansas WRRC Publication No. 46. pp. 1 357.

Kraemer, L. R. 1977. Corbicula manilensis Philippi in the Arkansas River: should the Corps of Engineers be concerned?