Korean J Parasitol.  2017 Feb;55(1):39-45. 10.3347/kjp.2017.55.1.39.

Platynosomum fastosum (Trematoda: Dicrocoeliidae) from Cats in Vietnam: Morphological Redescription and Molecular Phylogenetics

• Nguyen HM
• Van Hoang
• Ho LT

• KMID: 2374801
• DOI: http://doi.org/10.3347/kjp.2017.55.1.39

Abstract

The present study was performed to reveal the morphological characteristics and molecular phylogenetic position of Platynosomum fastosum Kossack, 1910. A total 167 specimens of P. fastosum were collected in 8 (4.9%) out of 163 sets of gall-bladders and bile ducts of cats. The number of worms was 1-105 per infected cat. This species was characterized by having a long and slender body, slightly larger ventral sucker than the oral sucker, indistinct prepharynx, small pharynx, short esophagus, bifurcation midway between 2 suckers, and ceca extending to the posterior end of the body. The length of the partial sequences of ITS1 and 5.8S rDNA of P. fastosum were 990 bp, GC-rich. AT/GC ratio was 0.9, there were 9 polymorphic sites, and intraspecific variations ranged from 0.1% to 0.9%. Phylogenetic analyses by neighbor-joining phylogram inferred from ITS1 rDNA sequences revealed that the genetic distance between P. fastosum specimens ranged from 0.3 to 1.5% while the smallest interspecific distance among dicrocoeliid species was 20.9 %. The redescription and genetic characters of P. fastosum are taxonomically important to recognize future different species of the genus Platynosomum showing high intraspecific and morphological variability.

Keyword

Platynosomum fastosum; nuclear ribosomal DNA; morphometry; phylogenetics; dicrocoeliid; hepatic trematode

MeSH Terms

Animals
Bile Ducts
Cats*
DNA, Ribosomal
Esophagus
Pharynx
Vietnam*
DNA, Ribosomal