Protistan parasite QPX of hard-shell clam Mercenaria mercenaria is a member of Labyrinthulomycota
http://www.int-res.com/articles/dao/42/d042p185.pdf

Mark A. Ragan, Greg S. MacCallum, Colleen A. Murphy, Jamie J. Cannone, Robin R. Gutell, Sharon E. McGladdery, Diseases of Aquatic Organisms


This Diseases of Aquatic Organisms scholarly article (PDF) reports that the Protistan parasite, QPX (Quahaug Parasite X) that affects the hard-shell clam Mercenaria mercenaria is a member of phylum Labyrinthulomycota, within which it appears as a specific relative of Thraustochytrium pachydermum. Obtained by DNA sequencing of the nuclear gene encoding the 18S RNA of the small-subunit ribosomal (ssu-rDNA) and subsequent phylogenetic analysis, these results confirm the provisional assignment of QPX to the Labyrinthulomycota made previously on the basis of morphological and ultrastructural characters found in some, but not all, geographic isolates.

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Subject: Biology:Ecology:Habitats:Marine, Biology:Ecology:Symbiotic Relations:Mutualism, Biology:Evolution:Patterns, Biology:Microbiology, Microbiology:Methods of Microbiology :Molecular Methods, Biology:Microbiology:Microbiology and Health
Resource Type: Scientific Resources:Research Results
Grade Level: Graduate/Professional, College Upper (15-16), College Lower (13-14)
Ocean Environments: Coastal and Estuarine
Topics: Biosphere:Evolution:Patterns, Biosphere:Microbiology, Ecology:Habitats:Marine, Biosphere:Methods of Microbiology:Molecular Methods , Biosphere:Ecology:Symbiotic Relations:Parasitism, Biosphere:Microbiology and HealthKeyword: Quahog Parasite Unknown