Byssus

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The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Byssus

 

(1) An excretion of the byssal gland, found in the so-called feet of many bivalve mollusks. Immediately upon expulsion, byssus hardens and forms durable silky filaments by which mollusks fasten themselves to underwater objects. In antiquity a special cloth, vysson, was prepared from the byssus excreted by the large mollusk pinna.

(2) A roe disease of freshwater fish caused by certain fungi of the genera Saprolegnia and Achy la.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Byssal thread production was also measured in juvenile mussels transplanted to high and low predation sites.
Attachment strength is related to the number and tensile strength of the byssal threads (including the plaque) and is a critical adaptive response for mussels, allowing them to resist dislodgment (Caro et al.
Mussel beds consist of one or more layers of individuals, attached to each other and to the substratum by a reticulum of byssal threads (Fig.
Salinity and sediment-mediated byssal thread production by Mytilus edulis Linnaeus and Geukensia demissa Dillwyn from New Jersey salt marshes.
Mussels of the Mytilidae, which includes all marine species, have a byssal complex with three main components: a root that is attached to the byssal retractor muscles; a stem that extends from the root and consists of a series of overlapping cuffs; and fibrous byssal threads that individually project off of each cuff (Bell and Gosline, 1996).
When compared with controls held at pH 8.1-8.2, pearl oysters (Pinctada fucata, Gould) held at pH 7.8 and pH 7.6 showed no significant difference in the number of byssal threads produced or total distance traveled.
These individuals were not included in the calculation of mean daily byssal thread production.
This increased byssal production in younger individuals has also been reported in Pinctada maxima, when individuals moved twice within a 24-h period and produced more new byssal threads, suggesting that when a pearl oyster voluntarily ejects the byssus, it can reattach more rapidly than after a mechanical severing (Taylor et al.
Clams and cockles bury themselves in the sand, oysters cement themselves to a rock or reef, and mussels use their "beards" of strong byssal threads to anchor themselves on rocks or pilings.
Truncilla macrodon was located by observing tracks in the substrate, such that one individual, for example, was attached to a conglomeration of sand by byssal threads. A fine deposit of mud layering the substratum was documented at our site, indicating a recent decrease in discharge.
For example, if byssal threads adjoin both valves at the ventral margin, valve movement and, therefore, foot extension, may be more limited than if the byssal threads were not attached near the gape.
After hatching from eggs, bay scallops go through a free-swimming stage before attaching themselves to submerged supports via secreted stems (byssal threads).