Stephanoprora amurensis sp. nov., Echinochasmus milvi Yamaguti, 1939 and E. suifunensis Besprozvannykh, 1991 from the Russian southern Far East and their phylogenetic relationships within the Echinochasmidae Odhner 1910

Abstract

Mature worms of Stephanoprora amurensis sp. nov. were obtained in an experimental study of its life cycle. In the Russian southern Far East, this trematode circulates using freshwater snails Parajuga subtegulata, freshwater fish and birds as the first, second intermediate and final hosts, respectively. Stephanoprora amurensis sp. nov. differs from the well-known representatives of Stephanoprora in a number of morphometric indicators of the developmental stages. The validity of the species was also confirmed by nuclear and mitochondrial DNA markers. In addition, new genetic data were obtained for Echinochasmus suifunensis and Echinochasmus milvi. An analysis of phylogenetic relationships within Echinochasmidae based on the 28S rRNA gene and ITS2 region identified two clusters, one of which combines species of Echinochasmus with 20–22 collar spines and short-tailed cercariae, and the other which includes Stephanoprora spp. and a number of representatives of Echinochasmus with 24 collar spines and long-tailed cercariae. The results of phylogenetic analysis based on ITS2 data show interfamily level of differences between the two clusters and intergeneric differentiation between the three subclusters uniting the species of Stephanoprora and Echinochasmus.

Echinostoma chankensis nom. nov., other Echinostoma spp. and Isthmiophora hortensis in East Asia: morphology, molecular data and phylogeny within Echinostomatidae

“…These factors provide strong grounds for considering East Asian and European worms to be of different species. Similar results were obtained for some representatives of Echinochasmidae Odhner 1910 (Tatonova et al ., 2020).…”

Molecular identification of trematode parasites infecting the freshwater snail Bithynia siamensis goniomphalos in Thailand

“…(2017) and Tatonova et al . (2020) all noted that Echinochasmus was not monophyletic in their molecular studies. Sequences of our cercaria and of E .…”

“…(2020). Cercariae of the two main clusters of Echinochasmus differ in morphology (Tatonova et al ., 2020). The ITS2 region (ON312616) had a 97.53% match with a number of sequences from E .…”

“…coaxatus fell within Cluster 1 of Tatonova et al . (2020). Cercariae of the two main clusters of Echinochasmus differ in morphology (Tatonova et al ., 2020).…”

“…Several amphistomes have been reported from Thailand. Sey & Prasitirat (1994) Tkach et al (2016), Besprozvannykh et al (2017) and Tatonova et al (2020) all noted that Echinochasmus was not monophyletic in their molecular studies. Sequences of our cercaria and of E. japonicus and E. coaxatus fell within Cluster 1 of Tatonova et al (2020).…”