title: Biomphalaria straminea (Mollusca: Planorbidae) as an intermediate host of Drepanocephalus spp. (Trematoda: Echinostomatidae) in Brazil: a morphological and molecular study.
abstract: Species of trematodes belonging to the genus Drepanocephalus are intestinal parasites of piscivorous birds, primarily cormorants (Phalachrocorax spp.), and are widely reported in the Americas. During a 4-year malacological study conducted on an urban lake in Brazil, 27-collar-spined echinostome cercariae were found in 1665/15,459 (10.7 %) specimens of Biomphalaria straminea collected. The cercariae were identified as Drepanocephalus spp. by sequencing the 18S (SSU) rDNA, ITS1/5.8S rDNA/ITS2 (ITS), 28S (LSU) rDNA region, cytochrome oxidase subunit 1 (CO1), and nicotinamide adenine dinucleotide dehydrogenase subunit 1 (ND1) markers. In experimental life cycle studies, metacercariae developed in laboratory-reared guppies (Poecilia reticulata); however, attempts to infect birds and rodents were unsuccessful. Two closely related morphotypes of cercariae were characterized. One species, identified by molecular markers as a genetic variant of Drepanocephalus auritus (99.9 % similarity at SSU, ITS, LSU; 97.2 % at CO1; 95.8 % at ND1), differs slightly from an archived North American isolate of this species also sequenced as part of this study. A second species, putatively identified as Drepanocephalus sp., has smaller cercariae and demonstrates significant differences from D. auritus at the CO1 (11.0 %) and ND1 (13.6 %) markers. Aspects related to the morphological taxonomic identification of 27-collar-spined echinostome metacercariae are briefly discussed. This is the first report of the involvement of molluscs of the genus Biomphalaria in the transmission of Drepanocephalus and the first report of D. auritus in South America.
authors.affiliation: Laboratório de Taxonomia e Biologia de Invertebrados, Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil, C.P. 486, 30123-970. hudsonalves13@ig.com.br.
authors.forename: Hudson A
authors.initials: HA
authors.lastname: Pinto
authors.affiliation: Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Stoneville, MS, 38776, USA.
authors.forename: Matt J
authors.initials: MJ
authors.lastname: Griffin
authors.affiliation: Warmwater Aquaculture Research Unit, Thad Cochran National Warmwater Aquaculture Center, U. S. Department of Agriculture, Stoneville, Stoneville, MS, 38776, USA.
authors.forename: Sylvie M
authors.initials: SM
authors.lastname: Quiniou
authors.affiliation: Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Stoneville, MS, 38776, USA.
authors.forename: Cynthia
authors.initials: C
authors.lastname: Ware
authors.affiliation: Laboratório de Taxonomia e Biologia de Invertebrados, Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil, C.P. 486, 30123-970.
authors.forename: Alan L
authors.initials: AL
authors.lastname: Melo
mesh_terms: D000818:Animals; D001700:Biomphalaria / Q000469:parasitology*; D001715:Bird Diseases / Q000469:parasitology / Q000635:transmission; D001717:Birds; D001938:Brazil; D058487:Cercaria / Q000033:anatomy & histology / Q000235:genetics; D002645:Chickens; D004275:DNA, Ribosomal / Q000737:chemistry; D004450:Echinostomatidae / Q000033:anatomy & histology / Q000145:classification* / Q000235:genetics; D003576:Electron Transport Complex IV / Q000235:genetics; D005819:Genetic Markers; D060106:Lakes; D008018:Life Cycle Stages; D051379:Mice; D011036:Poecilia; D018510:RNA, Helminth / Q000235:genetics; D017422:Sequence Analysis, DNA; D014201:Trematode Infections / Q000635:transmission / Q000662:veterinary
chemical_list: D004275:DNA, Ribosomal; D005819:Genetic Markers; D018510:RNA, Helminth; D003576:Electron Transport Complex IV
keywords: Biomphalaria; Cercariae; Drepanocephalus; Molluscs; Trematodes