Larvae metamorphose into juvenile mussels on the fish and then release from the host to find a suitable substrate, usually the gravel or sandy bottoms of streams and rivers with moderate currents. The glochidia parasitize the fish host for a variable length of time, likely depending upon water temperature, fish species and other factors. Recent research suggests that the required fish host for the Southern Clubshell is the Blacktail Shiner (Cyprinella venusta). Fish will be attracted to this lure and this increases the probability that fish will come in contact or consume the mass of larvae, thus allowing the glochidia to attach to the gills of the proper host fish. A conglutinate is a mass of glochidia that resembles a fish or another organism that is used to attract fish. Recent studies have determined that females release glochidia in the form of conglutinates. The parasitic glochidia must find and attach to the gills or fins of the appropriate host fish to complete development. Glochidia continue to develop and are released into the water column when fully matured. These fertilized eggs develop into special larva called glochidia. Sperm enters females through siphon-like regions and fertilization of eggs occurs within female shells. Male Southern Clubshell mussels release sperm into the shallow water of streams and rivers with moderate currents. Some of the specific details about the complex life cycle of Pleurobema decisum are not currently known, but the life history of this endangered mussel is presumed to be similar to related species. Young specimens have green rays or spots on portions of the outer shell surface. This thick-shelled species is more or less rectangular in shape and the periostracum (outer shell surface) is yellow to yellow-brown in color. View-only: Anyone with access to the file via link can only view it.The Southern Clubshell is a medium-sized freshwater mussel that averages about 2.8 inches (70 mm) in length.Edit: Anyone with access to the file via link can edit it.Off: Team members can specify their own default permissions for shared links.This setting controls the default permissions for shared links created by team members. Only people invited: Team members must invite someone to access the link they create.Anyone with link: Anyone can access shared links by default, regardless of whether or not they’re part of the team.Team members: Only team members can access shared links by default.This setting controls the default privacy of shared links created by team members. They don’t apply to Signatures activity, Dropbox Replay, Dropbox Capture, Dropbox Transfer, or “Send and track” links. These settings apply to files shared by links. Under the Allow sharing outside your team section, click Manage next to Share Capture links to open up Capture and manage shared links directly.This setting applies to links sent using Dropbox Capture. Under the Allow sharing outside your team section, click Manage next to Share Replay links to open up Replay and manage shared links directly.This setting applies to links sent using Dropbox Replay. Under the Allow sharing outside your team section, toggle Share files using Transfer on.This setting applies to files sent using Dropbox Transfer.
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