Prevalence and geographic range of Nadelspora canceri (Microspora) in Dungeness crab Cancer magister

Abstract

The prevalence and geographic distribution of Nadelspora canceri, a recently described microsporidian parasite of the Dungeness crab Cancer magister, was studied and prevalences were analyzed by sex and size of host crab and date of collection. Nadelspora canceri was widely distributed along the United States Pacific Coast in estuaries from Bodega Bay, California, to southern Washington. Prevalence of the parasite was high in crabs from most estuaries sampled, ranging from a low of 0.4 % (Gray's Harbor, Washington) to 41.2 (Tillamook Bay, Oregon) with an overall mean of 14 X . The parasite also occurred offshore of California and Oregon, but was not found in Puget Sound, Washington or in Glacier Bay, southeastern Alaska. The prevalence of infection in crabs captured in the open ocean was low (0.3%), and in crabs taken from nearshore at estuary mouths it was intermediate between estuarine and open-ocean levels. The infection was most prevalent (22.4 %) in 2 yr old crabs (13 cm carapace width) and males had approximately 2.5 times hlgher rate of infection than did females (10.7 vs 3.3 % ) No significant annual or seasonal variations in infection prevalence were detected.

Ameson metacarcini sp. nov. (Microsporidia) infecting the muscles of Dungeness crabs Metacarcinus magister from British Columbia, Canada

“…In contrast to Childers et al (1996) who found that N. canceri was 3 times more likely to infect male Dungeness crabs compared to females, we only observed gross signs of microsporidian infection (orange-colored joints) in female crabs from spring and fall assessments during the period from 2011 to 2013 and in the single sample from 2003. Prior to the current study, gross signs of infection were observed in 5 male crabs captured in 1998; however, the presence of microsporidia was not confirmed microscopically.…”

“…Olson et al (1994) in the original description of N. canceri only encountered needle-like spore forms infecting M. meta car cini. However, in a subsequent study, 3 of 1134 M. metacarcini infected with microsporidia were found to harbor a microsporidian with ovoid spores morphologically dissimilar to N. canceri (Childers et al 1996). Recent studies combining ecological, morphological, and molecular data have demonstrated significant plasticity in morphological features within certain taxa (Vossbrinck & Debrunner-Vossbrinck 2005, Stentiford et al 2010, 2013b.…”

“…The microsporidian N. canceri has unique needle-shaped spores and was originally described in Dungeness crabs from Alsea Bay, Oregon (Olson et al 1994), and was later identified in Dungeness crabs from Bodega Bay, California, to Gray's Harbor, Washington (Childers et al 1996). Prevalence of the parasite ranged from 0.4% in crabs from Gray's Harbor, Washington, to 41.2% in crabs from Tillamook Bay, Oregon.…”

“…Prevalence of the parasite ranged from 0.4% in crabs from Gray's Harbor, Washington, to 41.2% in crabs from Tillamook Bay, Oregon. The only other known reports of microsporidian infections in Dungeness crabs is the brief mention of an undescribed species (family Nosematidae) in 2 conference abstracts (Morado & Sparks 1988a,b), the mention of a microsporidian separate from N. canceri infecting 3 of 1134 Dungeness crabs from Puget Sound, Washington, and Winchester Bay, Oregon (Childers et al 1996), and the mention of an undescribed microsporidium causing 'pink crab' in a small percentage (<1%) of Dungeness crabs from Yaquina Bay, Oregon (www. dfw.…”

Enterospora canceri n. gen., n. sp., intranuclear within the hepatopancreatocytes of the European edible crab Cancer pagurus

“…Of those species described in decapods, the majority infect the skeletal muscle (Sprague 1970, 1977, Sprague & Couch 1971, Johnston et al 1978, Couch 1983, McGriff & Modi 1983, Herbert 1987, Alderman & Polglase 1988, Lightner 1988, Overstreet 1988, Flegel et al 1992, Dennis & Munday 1994, Olson et al 1994, Clotilde-Ba & Toguebaye 1995, Childers et al 1996, Mori & Salvido 2000, Azevedo 2001), whilst some, including Pleistophora spp., can also infect heart muscle and gill, stomach, hepatopancreatic epithelial cells (Overstreet 1973) and ovary (Viosca 1943, Sprague 1970. Few microsporidians have been described infecting the hepatopancreas alone (Azevedo 1987, Anderson et al 1989.…”