Systematic position and life cycle of Asymphylotrema macracetabulum comb. Nov. (Trematoda, Monorchidae)

Asymphylotrema macracetabulum (Belous, 1953) c. n. is described and diagnosis of the new genus Asymphylotrema in the subfamily Asymphylodorinae (the fam. Monorchidae) is given. The life cycle is studied and morphological characteristics of larval stages of this trematode in intermediate (freshwater molluscs Valvata sibirica and V. amurensis) and additional (Planaria sp.) hosts is given.     

Polylekithum percai n. sp. (Trematoda: Allocreadiidae) from Percichthys trucha (Perciformes: Percichthydae) in Patagonia,Argentina, and a redescription of Homalometron papilliferum (Szidat, 1956) n. comb.

Two species of Digenea are recorded from the intestine of Percichthys trucha (Percichthydae) from Patagonian water bodies. Polylekithum percai n. sp. (Allocreadiidae) is distinguished by its body size, the relative size of the suckers, the anterior extension of the vitelline fields, the number of eggs in the uterus and the different species of fish host from the two previously described species of Polylekithum. Homalometron (= Austrocreadium) papilliferum (Szidat, 1956) n. comb. is redescribed. Due to its spined tegument and the absence of a cirrus-sac, this species is considered a member of the family Apocreadiidae.