Table 2.

Parasites and pathogens associated with Gammarus roeselii (n = 156) during this study. The prevalence of each pathogen and parasite in the population sampled from Chojna, Poland, is stated alongside the reference image, if available

Parasite group	Species/Disease	Prevalence (%)	Image ref.
Viruses	Gammarus roeselii Bacilliform Virus	12.2	Fig. 2
	Putative gut virus	2.7	Fig. 1f
Bacteria	Epibiotic filamentous bacteria	100	Fig. 1b
	Putative rickettsia-like organism	< 1.0	Fig. 1g
Microsporidia	Cucumispora roeselii n. sp.	12.2	Figs. 3–5
	Microsporidium sp. from the hepatopancreas	< 1.0	Fig. 1j
Protists	Epibiotic, stalked, ciliated protists	83.9	Fig. 1a, b
	Epibiotic embedded ciliated protists	83.9	Fig. 1c
	Parasitic ciliated protists	< 1.0	Fig. 1d
	Gut-dwelling gregarines	50.0	Fig. 1e
Metazoa	Epibiotic rotifer	48.6	Fig. 1a
	Digenean trematodes	1.4	Fig. 1h
	Polymorphus minutus	1.4	Fig. 1i
	Pomphorhynchus sp.	4.1	No image