The only information I have is from
Natural infections of Nosema ceranae in European honey bees Fries et al
Journal of Apicultural Research 45(3): 230-233 (2006)

Quote
Although the differences in spore size between N. ceranae and  N. apis are
not immediately apparent in light microscopy, there is a consistent size
difference between the spores of the two species, with N. ceranae being
slightly smaller compared to N. apis (Fries et al., 1996). The length of
unfixed spores of N. ceranae isolated from A. cerana measure 4.7?0.46 ?m,
range 3.3 - 5.5 ?m, n=25.The width of the spores measure 2.7?0.25 ?m, range
2.3 - 3.0 ?m n=25 (Fries et al., 1996). Although there is a slight overlap,
with the smallest N. apis spores being smaller than the largest N. ceranae
spores, the average spore size of N. apis is approximately 1 ?m larger in
length . The spores of N. ceranae sometimes appear slightly bent which gives
a less consistent appearance compared to N. apis .
Unquote
Ruary

-----Original Message-----
On Behalf Of Mike Rowbottom

Do you have any data on the variability in dimensions of the two nosema
spores?

****************************************************
* General Information About BEE-L is available at: *
* http://www.honeybeeworld.com/bee-l/default.htm   *
****************************************************