title: Pathological Changes Associated with Eggs and Larvae of Unionicola sp. (Acari: Unionicolidae) Infecting Strophitus connasaugaensis (Bivalvia: Unionidae) from Alabama Creeks.
abstract: We detail gross and histopathological changes associated with infection by the eggs, larvae, and cuticular remnants of Unionicola sp. in the mantle, gill, and visceral mass of 25 Alabama creekmussels, Strophitus connasaugaensis, collected during May 2010 through July 2012 from 2 Alabama streams. A multitude (estimated mean intensity >100) of mite eggs and larvae typically infected mantle, gill, and visceral mass integument. Pathology associated with eggs (prevalence = 0.57) and larvae (prevalence = 0.39) typically consisted of localized distension of the infection site; a host response to these infections was indeterminate. However, larval mites embedded in suprabranchial connective tissues were typically encapsulated (prevalence = 0.89). Mite remnants (prevalence = 0.5) occurred in mantle, gill, visceral mass integument, foot, heart, pericardial gland, intestinal lamina propria, and were typically encapsulated. We speculate that S. connasaugaensis clears some infections but is recolonized by autoinfection or horizontal dispersal of mites in the stream. Noteworthy is that high-intensity infections seemingly do not markedly impact the histological picture of mussel tissues, indicating that mites are relatively benign symbionts that are of little concern to mussels under normal environmental conditions.
authors.affiliation: Department of Biological Sciences, College of Liberal Arts and Sciences, State University of New York at Oswego, 392 Shineman Center, Oswego, New York 13126.
authors.forename: Andrew
authors.initials: A
authors.lastname: McElwain
authors.affiliation: Department of Biological Sciences, College of Liberal Arts and Sciences, State University of New York at Oswego, 392 Shineman Center, Oswego, New York 13126.
authors.forename: Ryan
authors.initials: R
authors.lastname: Fleming
authors.affiliation: Department of Biological Sciences, College of Liberal Arts and Sciences, State University of New York at Oswego, 392 Shineman Center, Oswego, New York 13126.
authors.forename: Megan
authors.initials: M
authors.lastname: Lajoie
authors.affiliation: Department of Biological Sciences, College of Liberal Arts and Sciences, State University of New York at Oswego, 392 Shineman Center, Oswego, New York 13126.
authors.forename: Colleen
authors.initials: C
authors.lastname: Maney
authors.affiliation: Department of Biological Sciences, College of Liberal Arts and Sciences, State University of New York at Oswego, 392 Shineman Center, Oswego, New York 13126.
authors.forename: Brian
authors.initials: B
authors.lastname: Springall
authors.affiliation: Department of Biological Sciences, College of Liberal Arts and Sciences, State University of New York at Oswego, 392 Shineman Center, Oswego, New York 13126.
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Bullard
mesh_terms: D000053:Acari / Q000502:physiology* / Q000648:ultrastructure; D000407:Alabama; D000818:Animals; D005260:Female; D007814:Larva / Q000502:physiology / Q000648:ultrastructure; D008297:Male; D008855:Microscopy, Electron, Scanning; D009758:Nymph / Q000648:ultrastructure; D010063:Ovum / Q000502:physiology; D045483:Rivers; D049876:Unionidae / Q000469:parasitology*