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Mantle Cavity (mantle + cavity)

Distribution by Scientific Domains

Life Sciences	83%

Selected Abstracts

Larvae of Chironomids (Insecta, Diptera) Encountered in the Mantle Cavity of Zebra Mussels, Dreissena polymorpha (Bivalvia, Dreissenidae)

INTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 1 2005
Sergey E. Mastitsky
Abstract The paper includes data on species composition of chironomid larvae which were encountered in the mantle cavity of zebra mussels (Dreissena polymorpha) within 7 waterbodies in the Republic of Belarus. All were found to be free-living species commonly present in periphyton and/or benthos. A long-term study of the seasonal dynamics of these larvae in Dreissena did not reveal any typical pattern. Our data suppose that chironomids do not have an obligate association with zebra mussels and possibly enter their mantle cavity inadvertently. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

The biology and functional morphology of Arca noae (Bivalvia: Arcidae) from the Adriatic Sea, Croatia, with a discussion on the evolution of the bivalve mantle margin

ACTA ZOOLOGICA, Issue 1 2008
Brian Morton
Abstract In the Croatian Adriatic, Arca noae occurs from the low intertidal to a depth of 60 m; it can live for > 15 years and is either solitary or forms byssally attached clumps with Modiolus barbatus. The shell is anteriorly foreshortened and posteriorly elongate. The major inhalant flow is from the posterior although a remnant anterior stream is retained. There are no anterior but huge posterior byssal retractor muscles and both anterior and posterior pedal retractors. The ctenidia are of Type B(1a) and the ctenidial,labial palp junction is Category 3. The ctenidia collect, filter and undertake the primary sorting of potential food in the inhalant water. The labial palps are small with simple re-sorting tracks on the ridges of their inner surfaces. The ciliary currents of the mantle cavity appear largely concerned with the rejection of particulate material. The mantle margin comprises an outer and an (either) inner or middle fold. The outer fold is divided into outer and inner components that secrete the shell and are photo-sensory, respectively. The latter bears a large number of pallial eyes, especially posteriorly. The inner/middle mantle fold of A. noae, possibly representative of simpler, more primitive conditions, may have differentiated into distinct folds in other recent representatives of the Bivalvia. [source]

Larvae of Chironomids (Insecta, Diptera) Encountered in the Mantle Cavity of Zebra Mussels, Dreissena polymorpha (Bivalvia, Dreissenidae)

The biology and functional morphology of Humphreyia strangei (Bivalvia: Anomalodesmata: Clavagellidae): an Australian cemented ,watering pot' shell

JOURNAL OF ZOOLOGY, Issue 1 2002
Brian Morton
Abstract Amongst the watering pot shells of the Clavagellidae (Anomalodesmata), the least well known is Humphreyia, with a single species H. strangei. Unlike representatives of the other extant clavagellid genera, i.e. Clavagella and Brechites, however, where juveniles are unknown, there is a single juvenile (plus adult specimens) of H. strangei available for study. The Clavagellidae contains the weirdest of all bivalves, encased in a huge (in proportion to the tiny juvenile shell) adventitious tube with an anterior ,watering pot'. The juvenile H. strangei is dimyarian with a large foot and byssal groove, and a large pedal gape; the entire body is enclosed within a bag-like periostracum-covered mantle cavity. Upon permanent residence, however, the anterior watering pot component of the adventitious tube is cemented to the chosen substratum, the adductor muscles are lost and the foot and pedal gape greatly reduced; the fourth pallial aperture closes and the pedal gape and the tubules of the watering pot are similarly occluded. Once cementation is achieved, further growth anteriorly is impossible and the adventitious tube is secreted posteriorly, to house the long siphons, and subsequently can be added to as growth increments. Anatomically, H. strangei has a typical anomalodesmatan arrangement of mantle cavity and digestive organs so that it is, probably, a suspension feeder. Inside the pericardium, however, is a pair of unique proprioreceptors which probably serve to monitor rectal tonus and thus control defecation, co-ordinated with siphonal retraction and extension. They probably also prevent over-filling of the capacious rectum. It is believed that cementation and adventitious tube formation occur at the time of sexual maturity and this change in lifestyle between juvenile and adult represents a form of metamorphosis , quite distinct from that which occurs in all bivalves between the pediveliger and juvenile stages , and seems to be unique to Humphreyia and probably Brechites. This family of anomalodesmatan bivalves is thus actually stranger than the already aberrant watering pot would suggest. [source]

SOME LESSER KNOWN FEATURES OF THE ANCIENT CEPHALOPOD ORDER ELLESMEROCERIDA (NAUTILOIDEA, CEPHALOPODA)

PALAEONTOLOGY, Issue 3 2007
BJÖRN KRÖGER
Abstract:, Three specimens of the small breviconic ellesmeroceratid Paradakeoceras minor Flower, 1964 from the Tremadocian of the New York area preserve the annular elevation and muscle scars in moulds of the body chamber. The annular elevation is positioned at the base of the body chamber and is wider on the convex side of the shell than on the concave side. Multiple paired muscle scars can be seen within this annular elevation. A well-preserved body chamber of the breviconic ellesmeroceratid Levisoceras cf. edwardsi Ulrich, Foerste and Miller is described. Its body chamber shows a strong anterior,posterior asymmetry, which is common within the Ellesmeroceratida. The shape of the body chamber and of the soft body attachment structures has led to a reconstruction of an ellesmeroceratid soft body that is organized like a primitive conchiferan mollusc. Based on this reconstruction, a tryblidian cephalopod ancestor is supported. An evolutionary scenario is reconstructed from an ancestral nautiloid that is stretched along the anterior,posterior axis, and has serially arranged shell muscles and a small mantle cavity, towards a modern cephalopod with a dorsal,ventral body orientation, reduced number of shell muscles and a large mantle cavity. [source]