Mitogenomic and nuclear ribosomal transcription unit datasets support the synonymy of Paragonimus iloktsuenensis and P. ohirai (Paragonimidae: Platyhelminthes)

Nuclear ribosomal transcription units in Asian Paragonimus species (Paragonimidae: Platyhelminthes): structure, polymorphism, and implications for intersubordal phylogeny

“…The P. heterotremus species is a complex species found in northeastern India, southern and southwestern China, Laos, Myanmar, Thailand, and Vietnam (Le et al 2006;Singh et al 2009;Sanpool et al 2013;Blair 2019; Chai and Jung 2019). The P. ohirai species complex includes P. ohirai, P. iloktsuenensis, and P. sadoensis, all of which are clearly synonyms of the P. ohirai nominal species (Habe and Agatsuma 1985;Blair et al 1997; Le et al 2023) and are found in eastern China, Taiwan, parts of Japan, and Korea (Ryu et al 2000; Agatsuma and Habe 1986; Lee and Chung 2001). There is evidence of natural hybridization or genetic polymorphism between these two or three species (Agatsuma and Habe 1985;1986;Blair et al 1997; Le et al 2023).…”

“…The P. ohirai species complex includes P. ohirai, P. iloktsuenensis, and P. sadoensis, all of which are clearly synonyms of the P. ohirai nominal species (Habe and Agatsuma 1985;Blair et al 1997; Le et al 2023) and are found in eastern China, Taiwan, parts of Japan, and Korea (Ryu et al 2000; Agatsuma and Habe 1986; Lee and Chung 2001). There is evidence of natural hybridization or genetic polymorphism between these two or three species (Agatsuma and Habe 1985;1986;Blair et al 1997; Le et al 2023). The P. skrjabini miyazakii complex appears to have more species and subspecies.…”

“…Among 11 mtDNA sequences, there are seven mtDNA sequences of P. westermani: two strains from Korea (GenBank: AF540958 and AF219379), three strains from India (KX943544; KM280646; and CM017921), two strains from China (MN412705 and MN412706); two sequences of P. heterotremus: one from Vietnam (KY952166) and one from China (MH059809); and one sequence for each of P. ohirai (KX765277); P. iloktsuenensis (ON961029); and P. s. miyazakii (ON782295). However, few full nuclear ribosomal transcription units (rTUs) have been published to provide reference sequences for genetic comparisons among Paragonimidae species (Le et al 2023). In recent investigations, Le et al (2019;2023) produced two complete rTU-coding sequences from P. iloktsuenensis and P. ohirai and used their datasets to successfully support the synonymy between these two taxa.…”

“…However, few full nuclear ribosomal transcription units (rTUs) have been published to provide reference sequences for genetic comparisons among Paragonimidae species (Le et al 2023). In recent investigations, Le et al (2019;2023) produced two complete rTU-coding sequences from P. iloktsuenensis and P. ohirai and used their datasets to successfully support the synonymy between these two taxa. rTUs are hundreds of copies of sequentially repeated units contained in chromosomal nucleolar organizer regions (NORs) (Potapova and Gerton 2019).…”

“…In this study, we present near-complete rTU (coding region, from the 5' terminus of the 18S rRNA gene to the 3' terminus of the 28S rRNA gene) sequences from seven Paragonimidae species or strains, two of which were partially characterized in our earlier report (Le et al 2023). We determined the structure and order of the rTU-coding regions and gave thorough information about each ribosomal gene and intergenic region, with a focus on internal transcribed spacers (ITS1) and genetic composition.…”