Two new notocotylid trematodes from birds in Tasmania and their life histories

Abstract

Paramonostomwn caec•i n. sp., adults of which occur mainly in the intestinal caeca of Anas superciliosa, Cygnus atratus and I'oliocephalus pol1:ocephalus, is described. It is considered to closely resemble P. maleri.schi from which it differs in being only one-third the size, having a spinose tegument and a cirrus covered with tubercles. P. bur'Scte n. sp., adults of which have been found inhabiting the bursa of Fabricius of Anas super•cil•iosa is described and considered to be most similar to P. alveatum and P. parvum but to differ from them in the distribution of its vitellaria, the position of its ovary relative to the testes and in having a greater number of uterine loops. The domestic duck, Anas platyrhynchos, was found to serve as an experimental host for both new species. A brack ish water snail, Coxiella badgerensis, inhabiting Calverts Lagoon in southeast Tasmania serves as a natural intermediate host for P. caeci n.sp. and P. bursae n.sp. and also for two other undescribed notocotylids. Developmental stages (rediae, cercariae and meta cercariae) of both new Parmnonostomum species are described. The cercaria of I'. caeci n. sp. belongs to the Imbricata group, and that of P. bursae n.sp. to the Yenchingensis group.

Paramonostomum deseado n. sp. (Digenea: Notocotylidae) parasitizing the South American Black Oystercatcher and their atypical life cycle from the Patagonian coast

“…According to this classification, P. deseado n. sp. would belong to the ‘Elongate group’ with a size range between 608 and 784 μ m. The species that are near to this range (597–1130 μ m) are: P. caeci Smith and Hickman, 1983 from Australia, P. actitidis Cable et al ., 1960 from Caribbean and P. alveoelongatum Filimonova, 1971 from Russia (Cable et al ., 1960; Smith and Hickman, 1983; Filimonova, 1985). They differ in the genital pore position, P. deseado n. sp.…”

“…As far as is known, in the life cycles of the rest of the species of the genus and in the majority of notocotylids, the cercariae emerge from the snail and encyst on hard surfaces such as operculum, shell or in the substratum (Kulachkova, 1954; Cable et al ., 1960; Stunkard, 1967; Garkavi, 1968; Graefe, 1968; Velasquez, 1969; Smith and Hickman, 1983; Evans et al ., 1997). Studies of the life cycles of some notocotylid species that recorded the same snail as first and second intermediate hosts but it is not detailed where the metacercariae were found, e.g., Pseudocatatropis joyeuxi Kanev and Vassilev, 1986 encystment occurs ‘in the very body of the mollusc’ (Joyeux, 1922) or ‘inside the first intermediate host’ (Odening, 1966), Ps.…”

“…The internal encystment of metacercariae inside the rediae was corroborated in different sampling sites along the Patagonian coast. The transmission seems to be little affected because many notocotylid species use the same snail as the first and second intermediate host (encysting outside the redia) (Kulachkova, 1954; Cable et al ., 1960; Dollfus, 1966; Stunkard, 1967; Garkavi, 1968; Graefe, 1968; Velasquez, 1969; Winterbourn, 1973; Smith and Hickman, 1983; Evans et al ., 1997; Hechinger, 2012). However, the internal encystment (inside the redia) could result in energy optimization for the parasite, especially if the oystercatcher feeds on a limpet that strongly sticks to the substrate and has a hard shell.…”

“…Ten species (larval stages) of the genus Paramonostomum were previously recorded inhabiting marine and brackish habitats (Table 1), P. alveatum (Melhis in Creplin, 1846) Lühe, 1909; P. parvum Stunkard and Dunihue, 1931; P. pseudoalveatum Price, 1931; P. actitidis ; P. anatis ; P. chabaudi Van Strydonck, 1965; P. antarcticum ; P. philippinense Velasquez, 1969; P. bursae Smith and Hickman, 1983 and P. caeci (Kulachkova, 1954; Cable et al ., 1960; Stunkard, 1967; Garkavi, 1968; Graefe, 1968; Velasquez, 1969; Smith and Hickman, 1983; Evans et al ., 1997). None of these species has abbreviated life cycles, i.e., cercariae encyst within the redia.…”

Pronocephaloid cercariae (Platyhelminthes: Trematoda) from gastropods of the Queensland coast, Australia

“…However, other families of the order Littorinimorpha (Bithyniidae, Hydrobiidae, Littorinidae, Pomatiopsidae and Tateidae) have been reported extensively as hosts for notocotylids (e.g. Stunkard, 1960; Dollfus, 1966; Rohde & Onn, 1967; Graefe, 1968; Smith & Hickman, 1983). Vermetids have the form of tube-worms, forming asymmetrical calcareous tubes encrusting on rocks or among other substrates.…”