Redescriptions of two echinostomes from birds in Paraguay, with comments on Drepanocephalus Dietz, 1909 and Paryphostomum Dietz, 1909 (Digenea: Echinostomatidae)

Abstract

Two species of echinostomatid trematodes from Paraguayan birds are redescribed: these are Drepanocephalus spathans Dietz, 1909 from Phalacrocorax olivaceus and Paryphostomum segregatum Dietz, 1909 from Coragyps atratus. The genera Drepanocephalus Dietz, 1909 and Paryphostomum Dietz, 1909 are redefined and the species previously assigned to them reviewed. Paryphostomum mexicanum (Lamothe-Argumedo & Pérez-Ponce de León, 1989) n. comb. and P. parvicephalum (Rietschel & Werding, 1978) n. comb. are transferred from Drepanocephalus to Paryphostomum. A key to the species of Paryphostomum is presented, and the nominal species of Echinostoma Rudolphi, 1809, Nephrostomum Dietz, 1909 and Artyfechinostomum Lane, 1915 previously ascribed to this genus are commented upon. New combinations for species previously attributed to Paryphostomum are: Echinostoma pentalobum (Verma, 1936) n. comb.; E. baiyangdienense (Ku, Pan, Chiu, Li & Chu, 1973) n. comb.; Nephrostomum dollfusi (Agarwal, 1959) n. comb.; and Artyfechinostomum neotoma (Jain, 1953) n. comb. Species attributed to Paryphostomum which are here considered species inquirendae are: Paryphostomum (Lepustomum) mehrii Jain, 1953 sp. inq.; P. fragosum (Dietz, 1909) sp. inq.; P. horai Baugh, 1950 sp. inq.; P. huaccaci Ibáñez, 1974 sp. inq.; P. agrawali Gupta & Singh, 1986 sp. inq.; P. siddiqui Gupta & Singh, 1986 sp. inq.; P. durgensis Sapre, 1969 sp. inq.; and P. globorchum Oshmarin, 1970 sp. inq.

Experimental Bolbophorus Damnificus (Digenea: Bolbophoridae) Infections in Piscivorous Birds

“…This trematode was identified as D. spathans, which has been previously reported from this species (Threlfall, 1982;Fedynich et al, 1997;Flowers et al, 2004). Infections by trematodes in the genus Drepanocephalus have also been reported in other Phalacrocorax species (Nasir and Marval, 1968;Lamothe-Argumedo and PerezPonce de Leon, 1989;Kostadinova et al, 2002). Drepanocephalus spathans has not been reported to infect channel catfish.…”

“…However, a single gravid adult trematode was recovered from DCCO 1. This trematode was stained for morphologic comparison and identified as Drepanocephalus spathans (Yamaguti, 1958;Rietschel and Werding, 1978;Kostadinova et al, 2002;Jones et al, 2005).…”

The occurrence of metacercariae of Petasiger (Digenea: Echinostomatidae) in an unusual site, within the lateral line scales of cyprinid fishes

“…All measurements are given in micrometres unless otherwise indicated. For species identification, the keys of Kostadinova et al (2002) and Faltýnková et al (2008) were used.…”

“…After thawing, each intestine was cut open along its full length and its contents washed into a 1 litre glass beaker; the water was changed several times and the sediment checked for the presence of parasites. The trematodes found were studied unfixed and identified using the keys of Kostadinova (2005), Kostadinova et al (2002) and Faltýnková et al (2008). From the identified specimens, two Petasiger phalacrocoracis and three Paryphostomum radiatum, were selected for molecular studies.…”

Artyfechinostomum malayanum: Metacercariae Encysted in Pila sp. Snails Purchased from Phnom Penh, Cambodia

“…However, Premvati and Pande [24] acknowledged the genus Artyfechinostomum and synonymized A. sufrartyfex with A. malayanum . Kostadinova et al [33] were of opinion that A. sufrartyfex is probably conspecific with A. malayanum . However, a molecular study on internal transcribed spacers (ITS1 and ITS2) of rDNA revealed that the synonymy between A. malayanum and A. sufrartyfex seemed not valid because there were 18 variable nucleotide positions out of 699 sequences examined; among them 17 could be used as diagnostic positions between these 2 sibling species [29].…”