Some mussels release their glochidia inside a spongy, sticky mass called a conglutinate. The conglutinate sometimes resembles a prey item, such as a worm, which attracts the fish. When the fish bumps the conglutinate, it breaks apart and releases the glochidia, which attach to the fish. S. undulatus produces an interesting kind of conglutinate. It is whitish and rod-shaped, up to 7 millimeters long and contains around 12 glochidia.
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The conglutinate has a sticky filament that allows it to adhere to the substrate so it is not washed away. There is also an even more specialized way of dispersal known as a super-conglutinate. The super-conglutinate resembles an aquatic fly larva or a fish egg, complete with a dark area that looks like an eyespot,Watters, G. T. (1999). Morphology of the conglutinate of the Kidneyshell Freshwater Mussel, Ptychobranchus fasciolaris.
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The conglutinate has a sticky filament that allows it to adhere to the substrate so it is not washed away. There is also an even more specialized way of dispersal known as a super-conglutinate. The super- conglutinate resembles an aquatic fly larva or a fish egg, complete with a dark area that looks like an eyespot, and it is appetizing to fish. When a fish consumes it, it breaks up, releasing the glochidia.
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All Unionidae are known to use the gills, fins, or skin of a host fish for nutrients during the larval glochidia stage. Cyprogenia stegaria release into the water a conglutinate mimicking an Oligochaeta worm which contains the mussel's young. When a fish bites into the conglutinate lure, the young glochida are released and latch onto the fish's gills for nutrients.
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The motion helps to squeeze out the glochidia and it may help to attract fish hosts. Sometimes one of the glochidia will attach to a host while remaining attached to the conglutinate; in this case, the other glochidia in the structure may be dragged along with it and have an easier opportunity to parasitize the host.Watters, G. T. (2002). The kinetic conglutinate of the creeper freshwater mussel, Strophitus undulatus (Say, 1817).
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The conglutinate resembles a fly larva,Hartfield, P. and E. Hartfield. (1996). Observations on the conglutinates of Ptychobranchus greeni (Conrad, 1834) (Mollusca: Bivalvia: Unionoidea). American Midland Naturalist 135(2) 370-75. or perhaps a fish egg,USFWS.
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The glochidia of this species are larger than those of most other mussels, measuring up to almost 500 micrometers. The conglutinate moves by itself, making a pulsing motion. This may be caused by the swelling of the structure when it contacts the water.
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Its common name is Ouachita kidneyshell.Ptychobranchus occidentalis. NatureServe. 2012. This mussel packages its larvae, or glochidia, in a membranous conglutinate which resembles a small prey item. When a fish comes to investigate this lure, the glochidia attach to its gills and use it as a host during their development.
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Endangered status for eight freshwater mussels and threatened status for three freshwater mussels in the Mobile River drainage. Federal Register March 17, 1993. When this mussel breeds it releases its larvae, termed glochidia, glued together in packets called conglutinates. The conglutinate has a sticky filament that adheres to the substrate to prevent it from being washed away.
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The larvae, or glochidia, of Unionidae are known to use the gills, fins, or skin of a host fish for nutrients during their development. Ptychobranchus fasciolaris enclose their glochidia in a membranous capsule called a conglutinate that resembles an insect larva or small fish. When a host fish bites the capsule bait, the Ptychobranchus fasciolaris glochidia attach to its gills, where they feed.
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