Bolbophorus damnificus n. sp. (Digenea: Bolbophoridae) from the channel catfish Ictalurus punctatus and American white pelican Pelecanus erythrorhynchos in the USA based on life-cycle and molecular data

Abstract

The common pathogenic prodiplostomulum metacercaria in the flesh, mostly near the skin, of pond-produced channel catfish Ictalurus punctatus has been demonstrated to be Bolbophorus damnificus Overstreet & Curran n. sp. The catfish acquires the infection from the snail Planorbella trivolvis, the only known first intermediate host, and the species is perpetuated through the American white pelican Pelecanus erythrorhynchos, as confirmed by experimental infections with nestling and dewormed adult pelican specimens in conjunction with molecular data. It differs from the cryptic species Bolbophorus sp., also found concurrently in the American white pelican, by having eggs 123-129 microm rather than 100-112 microm long and consistent low values for nucleotide percentage sequence similarity comparing COI, ITS 1/2, 18S rRNA and 28S rRNA fragments. Bolbophorus sp. is comparable but most likely distinct from B. confusus (Kraus, 1914), which occurs in Europe and has eggs 90-102 microm long. Its intermediate hosts were not demonstrated. The adults of neither of the confirmed North American species of Bolbophorus were encountered in any bird other than a pelican, although several shore birds feed on infected catfish, and B. damnificus can survive but not mature when protected in the mouse abdominal cavity. B. ictaluri (Haderlie, 1953) Overstreet & Curran n. comb., a species different from B. damnificus, is considered a species inquirenda.

Parasites of the American White Pelican

“…Overstreet et al (2002) have shown that at least some of those records represent one and in some cases two related species of Bolbophorus. Whether B. confusus, which we consider to be a European species, exists in North America still has to be determined (Overstreet et al 2002).…”

“…Whether B. confusus, which we consider to be a European species, exists in North America still has to be determined (Overstreet et al 2002). One of the two species previously reported in part as B. confusus by at least some authors (e.g., reviews by Olson 1966, Overstreet et al 2002, Appendix 1) was considered as B. damnificus, and it can be readily acquired by the AWP from feeding on infected channel catfish (Ictalurus punctatus) (Overstreet et al 2002, Overstreet andCurran 2004). The other species is referred to as Bolbophorus sp.…”

The occurence of black spot disease in Astyanax aff. fasciatus(characiformes: characidae) in the Guaíba Lake basin, RS, Brazil

“…The disease is usually caused by the metacercaria stage of several species from different digenetic trematodes genres and families (usually Diplostomidae) (Overstreet et al, 2002).…”

“…The life cycle of these trematodes is complex, involving a series of at least 3 hosts, thus several fish serve as intermediate host in the development of the parasite. Usually the adult parasites are located in the piscivorous bird's intestine (Overstreet et al, 2002).…”

Infection by a black spot-causing species of Uvulifer and associated opercular alterations in fishes from a high-desert stream in Wyoming

“…When an adult is unknown and a diplostomoid metacercariae lacks pseudosuckers but encysts, that digenean is referred to as Neascus (e.g. Overstreet et al 2002). The life cycle of these trematodes is complex, involving a series of at least 3 hosts with various fishes serving as a second intermediate host in the development of the parasites.…”