Dr. Murai Éva szerk.: Parasitologia Hungarica 23. (Budapest, 1990)

MATERIAL AND METHODS In the period between 1962 and 1989 more than 200 muskrats were examined for helminth parasites (185 specimens from Fertőrákos, Lake Fertő and 17 specimens from Keszthely, Lake Balaton). The hosts were captured by various techniques and methods and dead animals were dissected in fresh condition. After removal from the organs in question, the flukes were fixed in 70 % alcohol and whole mounts were stained in carmine. RESULTS Skrjabinoplagiorchis ondatrae (Andrejko, 1965) (Fig. 1) Description Body medium in size, elongate oval in form, 1.6-2.0 mm long and 0.1-0.5 mm wide. Cuticle with small spines along its length. Oral sucker terminal 0.25-0.41 by 0.21-0.41 mm in size, pharynx 0.20-0.20 by 0.18-0.20 mm in size; oesophagus absent; caeca in lateral field, extending to posterior extremity of body. Ventral sucker 0.30-0.35 by 0.30-0.35 mm in size. Testes lying symmetrically in posterior part of body; they are elongated oval; right testis 0.60-0.80 by 0.30-0.35 mm, left testis 0.48-0.75 by 0.30-0.35 mm in size. Vas deferens running medially. Cirrus pouch well developed, arcuate in position in middle region in front of ventral sucker, 0.35-0.40 by 0.20 mm in size. It contains oval and convoluted seminal vesicle and pars prostatica. Ovary entire, on right side to ventral sucker, measuring 0.25-0.35 by 0.25-0.30 mm. Uterus strongly developed, situated in area between ventral sucker and caecal ends, mostly intertesticular. Uterine eggs oval, 70-80 by 35-40 mm with miracidia. Genital pore left to median line, in front of ventral sucker. Vitellaria strongly developed, follicules small, extending along both sides from pharynx to extremity of body; anteriorly they penetrate to median fields. Excretory pore at tip of posterior extremity. Host: Ondatra zibethicus Habitat: liver (biliary duct). Distribution: Moldavia, Hungary (Lake Fertő, Lake Balaton). Specimens: (4 expl.) Department of Zoology, University of Agricultural Science, Keszthely, Hungary. Troglotrema srebarni Genov, 1964 (Fig. 2) Description Body small, pyriform, 0.85-1.2 mm long and 0.70-0.98 mm wide at level of ventral sucker. Cuticle with spines along whole body. Oral sucker 0.32-0.34 by 0.24-0.36 mm in size; pharynx 0.09-0.10 by 0.12-0.14 mm in size; oesophagus absent, caeca in lateral fields, extending to posterior extremity. Ventral sucker in anterior half of body, median, 0.25-0.27 by 0.22-0.24 mm in size. Testes lying symmetrically or slightly diagonal. Right testis 0.33-0.38 by 0.22-0.29 mm, left testis 0.25-0.32 by 0.23-0.31 mm in size.