title: Morphological and molecular differentiation of Clinostomum complanatum and Clinostomum marginatum (Digenea: Clinostomidae) metacercariae and adults.
abstract: The separation of Clinostomum complanatum Rudolphi, 1814 and Clinostomum marginatum Rudolphi, 1819 has long been unclear. Recent data confirm the validity of the junior species, C. marginatum , by ∼ 1% differences in its 18S rDNA sequences. We collected adults and metacercariae of C. complanatum and C. marginatum and found reliable morphological differences in the genital complex at both developmental stages. In addition, we identified basic morphometrics (distance between suckers, body width) in metacercariae that may be useful for discriminating the species. The morphological differences were supported by the comparison of sequences of internal transcribed spacers of ribosomal DNA and of the mitochondrial gene cytochrome c oxidase I (COI) from 39 specimens. In 36 specimens, the average divergence between the species was 7.3% in ITS and 19.4% in COI sequences. Two specimens from North America and 1 from Europe had sequences that did not allow them to be clearly allied with either species.
authors.affiliation: Department of Veterinary Medical Sciences, Alma Mater Studiorum Università di Bologna, Via Tolara di Sopra 50, 40064 Ozzano Emilia (BO), Italy. monica.caffara@unibo.it
authors.forename: Monica
authors.initials: M
authors.lastname: Caffara
authors.forename: Sean A
authors.initials: SA
authors.lastname: Locke
authors.forename: Andrea
authors.initials: A
authors.lastname: Gustinelli
authors.forename: David J
authors.initials: DJ
authors.lastname: Marcogliese
authors.forename: Maria L
authors.initials: ML
authors.lastname: Fioravanti
mesh_terms: D000818:Animals; D001001:Anura; D001717:Birds; D004272:DNA, Mitochondrial / Q000737:chemistry; D004275:DNA, Ribosomal / Q000737:chemistry; D021903:DNA, Ribosomal Spacer / Q000737:chemistry; D016002:Discriminant Analysis; D003576:Electron Transport Complex IV / Q000235:genetics; D005399:Fishes; D050259:Genes, Mitochondrial / Q000235:genetics; D007558:Italy; D058488:Metacercariae / Q000033:anatomy & histology / Q000145:classification / Q000235:genetics; D008969:Molecular Sequence Data; D009656:North America; D016133:Polymerase Chain Reaction; D025341:Principal Component Analysis; D012335:RNA, Ribosomal / Q000235:genetics; D016415:Sequence Alignment; D014200:Trematoda / Q000033:anatomy & histology / Q000145:classification* / Q000235:genetics
chemical_list: D004272:DNA, Mitochondrial; D004275:DNA, Ribosomal; D021903:DNA, Ribosomal Spacer; D012335:RNA, Ribosomal; D003576:Electron Transport Complex IV