Formwachstumsversuche an Sphaerium corneum

1. Crepidostomum farionis inhabits the gall bladder, as well as the intestine and pyloric caeca, of the trout and grayling.2. The life history of Crepidostomum farionis has been worked out and is based on the similarity of organisation of the cercaria, encysted larval trematode and the adult.3. The first intermediate hosts in the life history of this trematode are Pisidium amnicum (Müll.) and Sphaerium corneum (L.) though the latter is unusual.4. The second intermediate host is the larva of the mayfly, Ephemera danica (Müll.).5. There are two generations of rediae, the first gives rise to daughter rediae, which in turn produce cercariae.6. The rediae are characterised by the absence of ambulatory processes and a functional intestine.7. The cercaria (n.sp.) possesses “eye spots,” stylet and gland cells (salivary?), and the excretory vesicle is tube-shaped.8. The excretory system of the redia and the cercaria has been worked out in detail.9. The relation of the parasites to their respective hosts is discussed. On account of the need for further observations definite conclusions are held over for a later paper.

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Zur tagesperiodizität der filtrationsleistung von Dreissena polymorpha und Sphaerium corneum (Bivalvia)

Hydrobiologia ◽

10.1007/bf00016534 ◽

1980 ◽

Vol 69 (1-2) ◽

pp. 45-48 ◽

Cited By ~ 15

Author(s):

H. -G. Benedens ◽

W. Hinz

Keyword(s):

Dreissena Polymorpha ◽

Sphaerium Corneum

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Memoirs: On the Anatomy of Cerearia Macrocerca from Spliaerium Corneum

Journal of Cell Science ◽

10.1242/jcs.s2-82.326.311 ◽

1940 ◽

Vol s2-82 (326) ◽

pp. 311-326

Author(s):

G. G. VICKERS

Keyword(s):

Mechanical Effect ◽

Excretory Vesicle ◽

Large Numbers ◽

Sphaerium Corneum ◽

Gill Lamellae

A detailed anatomical description is given of the sporocyst and cercaria of Cercaria macrocerca (Fil.) from the gills of Sphaerium corneum (Linn.). The development of the large cells surrounding the excretory vesicle of the cercaria is described. It has been found that the granules with which these cells are packed originate round the nucleus and afterwards migrate towards the lumen of the vesicle. These granules do not appear to be discharged on encystment of the cercaria to act as cystogenous material; they are shed gradually into the excretory vesicle, and it is therefore natural to suppose that they are granules of excretory material. In heavy infestations the mechanical effect of large numbers of sporocysts between the gill lamellae of the host completely prevents reproduction of the mollusc. Cercariae escaping from the sporocysts continually rupture the gill lamellae of the host, and large areas of the gills are thus put out of action.

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Recent distribution of Sphaerium nucleus (Studer, 1820) (Bivalvia: Sphaeriidae) in the Czech Republic

Malacologica Bohemoslovaca ◽

10.5817/mab2008-7-26 ◽

2008 ◽

Vol 7 ◽

pp. 26-32

Author(s):

Tereza Kořínková ◽

Luboš Beran ◽

Michal Horsák

Keyword(s):

Czech Republic ◽

Human Impact ◽

Conservation Status ◽

Water Bodies ◽

Lowland River ◽

Museum Collections ◽

The Czech Republic ◽

Small Water ◽

Sphaerium Corneum ◽

Voucher Specimens

Recent data about the distribution of Sphaerium nucleus in the Czech Republic are summarized and used in an attempt to evaluate its conservation status. During the last ten years, this species was found at 40 sites, mostly shallow small water bodies situated in lowland river alluviums. These types of habitats are generally endangered due to the huge human impact and exploration of these areas. The revision of voucher specimens of Sphaerium corneum s.lat. deposited in museum collections yielded a further 22 old records of S. nucleus.

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Croissance et productivité d'une population du Sphaerium corneum (L.) (Bivalvia: Pisidiidae)

Canadian Journal of Zoology ◽

10.1139/z88-063 ◽

1988 ◽

Vol 66 (2) ◽

pp. 439-445 ◽

Cited By ~ 2

Author(s):

Jean-Michel Le Gallo ◽

Jean-Claude Moreteau

Keyword(s):

Growth Rate ◽

Growth Function ◽

Von Bertalanffy ◽

Daily Growth ◽

Small Stream ◽

Sphaerium Corneum ◽

Von Bertalanffy Growth Function ◽

Field Data Analysis ◽

Annual Mortality ◽

Ecological Differences

The growth pattern of Sphaerium corneum from a small stream population (Mérantaise, Île-de-France) has been established from the analysis of annual modal evolution. Preliminary data obtained by other authors suggested that the von Bertalanffy growth model was the most suitable, but that the growth rate varied with the season. The largest and smallest heights of animals observed in the field allowed us to determine the parameters of the model: H (asymptotical height) = 11.5 mm and h0 (initial height) = 2 mm. The daily growth rate (k) varied from 2.5 × 10−4 in November to 4.3 × 10−3 in May and its seasonal variation is described with a model that allows its incorporation into the von Bertalanffy growth function. Mortality was studied considering the evolution of cohort size; the annual mortality rate was about 80%, which suggests a 3-year life-span. Productivity was estimated by analysis of a theoretical cohort evolution and by field data analysis. Productivity (P) determined from monthly samplings varied between 9 and 10.3 g m−2 according to the method; the productivity to biomass per square meter ratio (P/B) was between 3.7 and 4.4. The same ratio obtained from the theoretical cohort was 4.5. Comparison of these values with those reported by other workers reveals notable variations that might be related to ecological differences in the ecosystem.

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Vodní měkkýši Labe mezi Pardubicemi a Hřenskem [Aquatic molluscs of the Elbe River between Pardubice and Hřensko (Czech Republic)]

Malacologica Bohemoslovaca ◽

10.5817/mab2002-3-78 ◽

2005 ◽

Vol 3 ◽

pp. 78-88

Author(s):

Luboš Beran

Keyword(s):

Czech Republic ◽

Dreissena Polymorpha ◽

Native Species ◽

Corbicula Fluminea ◽

Elbe River ◽

Bithynia Tentaculata ◽

Sphaerium Corneum ◽

Theodoxus Fluviatilis ◽

The Elbe River ◽

Radix Auricularia

Aquatic molluscs of the Elbe River between Němčice (near Pardubice, Eastern Bohemia, Czech Republic) and Hřensko (Northern Bohemia, Czech Republic) at 27 localities were investigated from 1994 to 2004. Altogether 40 species (24 gastropods, 16 bivalves) from 77 species known on the territory of the Czech Republic were found at sites under study. A gradual invasion of 6 non-native species (Potamopyrgus antipodarum, Physella acuta, Menetus dilatatus, Ferrissia clessiniana, Corbicula fluminea) and an extinction of another species (Theodoxus fluviatilis, Planorbis carinatus, Unio crassus, Pisidium amnicum) were documented in comparison with historical records. Rare mussel Pseudanodonta complanata and rare pea mussel Pisidium moitessierianum were found at several localities under study and these finds document survival of these bivalves in the Elbe River. Molluscan communities of particular localities were most often usually compounded from species Viviparus viviparus (downstream of loc. 9), Bithynia tentaculata, Radix auricularia, Radix ampla, Unio pictorum, Anodonta anatina, Corbicula fluminea (downstream of loc. 8), Sphaerium rivicola (downstream of loc. 7), Sphaerium corneum s. lat., Pisidium supinum, Dreissena polymorpha.

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Changes of malacofauna in a small lowland river in eastern Poland

Annales Universitatis Paedagogicae Cracoviensis Studia Naturae ◽

10.24917/25438832.5.5 ◽

2020 ◽

pp. 66-80

Author(s):

Beata Jakubik ◽

Krzysztof Lewandowski ◽

Aleksandra Biernat

Keyword(s):

Species Richness ◽

Species Composition ◽

Left Bank ◽

Lowland River ◽

Anodonta Cygnea ◽

Bithynia Tentaculata ◽

Sphaerium Corneum

In 2016, the species composition and the structure of the dominance of molluscs in the Muchawka River (left-bank tributary of the Liwiec River) were assessed. The occurrence of 19 species of molluscs were recorded, including 11 species of snails and 8 species of mussels. The eudominant was Pisidium casertanum, which, only in the last two sites, constituted 43.1% of all molluscs. Two other species of molluscs from the Sphaeriidae family were also eudominants – Pisidium subtruncatum (22.8%) and Sphaerium corneum (10.3%). Snails were most frequently represented by the dominant Bithynia tentaculata, constituting 5.4% of all molluscs, and the subdominant Bathyomphalus contortus at 2.8%. Sixteen years after the first malacological analysis, an increase in species richness and differences in the dominance of molluscs were found in the Muchawka River. Clams from the Sphaeriidae family invariably dominated but with a different species composition. The disappearance of the protected Anodonta cygnea and Sphaerium rivicola has been noted, and the occurrence of the protected Unio crassus has also been noted.

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