Dr. Murai Éva szerk.: Parasitologia Hungarica 18. (Budapest, 1985)
other hand further new information on the amphistomes of Vietnamese vertebrates are preS' ented. MATERIALS AND METHODS The majority of the test material of fishes, amphibians and turtles (Tesjcudj^ejtongjata^ Z* impjr_3ssa_ T£^nyji_steijidacjineri) were collected from hosts deposited in formaline in the Department of Vertebrate Zoology, Hanoi University, and the lesser part of it was bought at the Hanoi market. The test material of mammalian hosts is deposited at the Department of Parasitology, Vietnamese Scientific Research Center, Hanoi, collected from Bos_prj.mJ.g_enius f. taurus, Bubah^j3_arnee_f. bubalia, Capjja_ae^a_rjgu s f . hifcus, Çeryus^nicolor, Muntiacus muntjak and Su_s^c_rofa_f. domestica. Whole mounts were stained in carmine, median sagittal sections were prepared by the usual method and the technique applied for examination of surface topography was the same as described by the author elsewhere (SEY, 1985b). RESULTS AND DISCUSSION Amphistomes were recovered from all of the vertebrate groups except reptiles (turtles). AMPHISTOMES OF FISHES Helminth parasites of freshwater fishes have been infrequently investigated (OSHMARIN, 1965; HA KI, 1969; SEY, 1969a). Of the trematodes described, one species of amphistome, Amurotrema dombrowskajae was recorded by HA KI (19 69) from SpjniJ3arJ^cJ_thy_s_o_^^ _tus__ I have found this species in the same host. Histomorphological examination of its muscular organs showed that it had a new type of pharynx, Amurotrema (characterized by primary pharyngeal sacs longer than the pharynx itself, as well as by the presence of a moderately developed middle circular layer. Fig. 13). The acetabulum is of a Cleptodiscus-type (SEY, 1986b). Further three fish amphistomes (Neocladorchis multilobularis , Platycladorchis microace- tabularis , P. macroacetabularis) have been described elsewhere (SEY, 1986 a). AMPHISTOMES OF AMPHIBIANS Two species of amphistomes ( Diplodiscus amphichrus Tubangui, 1933 and D. mehrai Pande, 1937) were found in frogs and salamaders. The former species was described for the first Legend to figures Figs 1-12: Scanning electron microscopy of surface topography: 1-3 Gastrodiscoides hominis (1= general view of oral opening, X54; 6-7 genital opening, 6= X190, 7= X695); 4-7 Orthocoelium saccocoelium (4-5 general view of oral opening, 4= X81, 5= X196, 6-7 genital opening, 6=X85, 7= X180); 8-10 Gastrothylax crumenifer (8-9 general view of oral opening, 8= X78, 9= X266, 10= genital opening, X73); 11-12 Carmyerius synethes (general view of oral opening, 11= X186, 12= X990). Figs 13-30: Median sagittal sections of muscular organs: Amurotrema dombrowskajae (13 = pharynx), Diplodiscus amphichrus (14= pharynx), D. mehrai (15= pharynx), Hawkesius hawkesi (16= pharynx, 17= genital opening, 18= dorsal and 19 = ventral halves of acetabulum), Paramphistomum ichikawai (20= genital opening, 21= dorsal half of acetabulum), Calicophoron microbothrioides (22= oesophagus, 23= genital opening, 24= dorsal half of acetabulum), Orthocoelium dinniki (25 = oesophagus, 26= genital opening), O. saccocoelium (29 = pharynx, 30 = genital opening, 27 = dorsal and 28= ventral half of acetabu lum).
