A new species of Dactylogyrus (Monogenea: Dactylogyridae) parasitic on an endangered freshwater fish, Rhodeus atremius atremius, endemic to Japan

Cophylogenetic relationships betweenDactylogyrus(Monogenea) ectoparasites and endemic cyprinoids of the north‐eastern European peri‐Mediterranean region

“…Dactylogyrus Diesing, 1850 (Monogenea) are gill parasites generally exhibiting narrow host specificity and high morphological variability with respect to attachment organ (termed haptor), putatively reflecting adaptations to their different host species or within‐host microhabitats (Gibson, Timofeeva, & Gerasev, ; Šimková, Desdevises, Gelnar, & Morand, , ; Šimková & Morand, ; Šimková, Verneau, Gelnar, & Morand, ). In addition, Dactylogyrus currently represents the platyhelminth genus with the highest species diversity (more than 900 described species according to Gibson et al, ), certainly largely underestimated as new species have recently been described (Aydogdu, Molnár, Emre, & Emre, ; Benovics, Kičinjaová, & Šimková, ; Nitta & Nagasawa, ; Rahmouni, Řehulková, Pariselle, Rkhami, & Šimková, ). This high species richness in Dactylogyrus is associated with their narrow host specificity towards a single host species or closely related species, and with a high diversity of their host species—primarily freshwater fish of Cyprinoidea (considering recent phylogenetic studies, for example Schönhuth, Vukić, Šanda, Yang, & Mayden, ).…”

Dactylogyrids (Platyhelminthes: Monogenea) from Sudanese Labeo spp., with a description of Dogielius sennarensis n. sp. and a redescription of Dogielius fl osculus Guégan, Lambert & Euzet, 1989

“…Therefore, recently there is a trend of increasing number of new monogenean species being described predominantly from the tropical regions (e.g. Musilová et al, 2009; Přikrylová et al, 2009; Knoff et al, 2015; Pulido-Flores et al, 2015; Soo et al, 2015; Nitta & Nagasawa, 2016). Dactylogyrid monogeneans mainly infect freshwater cyprinids (Teleostei: Cypriniformes), with the suborder Dactylogyrinea Bychowsky, 1937 being the most numerous and diverse group (Cribb et al, 2002).…”

Redescription of <i>Dactylogyrus petruschewskyi</i> Gussev, 1955 (Monogenea: Dactylogyridae), a Newly Recorded Alien Monogenean from an Alien Cyprinid, <i>Megalobrama amblycephala</i> Yih, 1955 (Cypriniformes: Cyprinidae), in Ibaraki Prefecture, Central Japan

“…The internal structure of D. petruschewskyi has not been described. The results of our redescription show a common morphological feature between this species and D. bicorniculus Nitta and Nagasawa, 2016, which is the only closely related species whose internal morphology has been described (Nitta and Nagasawa 2016): both the prostatic reservoirs are round and small; the vagina is not sclerotized and leads parallel to the seminal receptacle; the vas deferens and the seminal vesicle do not extend above the male copulatory organ; and the testis is pyriform and located posterodorsal to the germarium. Even in recent years, the internal morphological descriptions of Dactylogyrus species are often neglected.…”

“…Drawings were made with the aid of a drawing tube fitted on an Olympus BX60 light microscope. Sclerotized parts were measured following the methods reported by Nitta and Nagasawa (2016). All measurements are in micrometers and given as the range followed by the mean and the number (n) of specimens examined in parentheses.…”

“…As found through a BLAST search, the newly obtained partial 28S rDNA sequence (LC538183) was identical to D. petruschewskyi (AY548927). Although this accession sequence has been used for molecular phylogenetic studies on dactylogyrids Liao 2004, 2005;Šimková et al 2006, 2017Singh and Chaudhary 2010;Rajvanshi and Agrawal 2013;Tan 2013;Mendoza-Palmero et al 2015, 2017Nitta and Nagasawa 2016, 2017Chiary and Singh 2019;Daghigh Roohi et al 2020), the sequence data were not based on a published record of specimens morphologically identified. The present results support the correctness of the identification.…”