First record of viviparity in polystomatid flatworms (Monogenea: Polystomatidae) with the description of two new species of Madapolystoma from the Madagascan anuran hosts Blommersia domerguei and Mantella expectata

Abstract

Two frog species, Blommersia domerguei and Mantella expectata, are reported as hosts for new species of Madapolystoma. Phylogenetic analyses and genetic divergences observed in the genus supported the distinction of two morphotypes infesting selectively each host species and morphological investigation combining marginal hooklet morphometrics, genital spine number and measurements further showed that polystomes from the two host species differed from each other and from all other known polystomes. Madapolystoma magnahami n. sp. and Madapolystoma isaloensis n. sp. are therefore described as two new species. Advanced in utero development was illustrated in both polystome species following the observation of well developed hamuli and two pairs of haptoral suckers in developing embryos. Inside some of these in utero embryos a F2 generation embryo was also observed. This is the first report of true viviparity among polystomatid flatworms.

First record of Metapolystoma (Monogenea: Polystomatidae) from Boophis tree frogs in Madagascar, with the description of five new species

“…While Boophis is not the single representative of the family Mantellidae infected by polystomes in Madagascar, mantellid frogs of the two genera Mantella and Blommersia which both exhibit a derived mode of reproduction, are infected by polystomes of another genus, i.e. Madapolystoma (see Verneau et al, 2009 ; Du Preez et al, 2010 ; Landman et al, 2018 ). In addition, Verneau et al (2009) reported another undescribed species of Metapolystoma from Aglyptodactylus madagascariensis (Duméril, 1853).…”

“…When it comes to amphibian diversity, Madagascar is globally ranked in the top twelve ( Andreone et al, 2008 ). Its unique herpetofauna serve as hosts for an equally unique and diverse assemblage of parasites (see Wohltmann et al, 2007 ; Junker et al, 2010 ; Rocha et al, 2012 ; Kuzmin et al, 2013 ; Landman et al, 2018 ). However, little is known about Madagascar's anuran polystome flatworm diversity, since only 86 of the 356 known frog species ( Frost, 2020 ) have been screened for polystomes at a few accessible localities in the past ( Verneau et al, 2009 ).…”

“…Besides these two species, Kankana manampoka Raharivololoniaina et al 2011 was described from Cophyla pollicaris (Boulenger, 1888). Five other species of Madapolystoma were reported from mantellids, namely Madapolystoma biritika Du Preez et al (2010) from Mantella madagascariensis (Grandidier, 1872), M. isaloensis Landman et al (2018) from Mantella expectata Busse and Böhme, 1922 and M. magnahami Landman et al (2018) from Blommersia domerguei Guibé, 1974. Madapolystoma cryptica Berthier et al 2014 and M. ramilijaonae Berthier et al 2014 were conversely described from the same host species Guibemantis liber (Peracca, 1893).…”

“…Up to the present, the three known Metapolystoma species have been described from grass frogs belonging to Ptychadena : M. brygoonis from P. mascareniensis in Madagascar, M. cachani ( Gallien, 1956 ) from Ptychadena longirostris (Peters, 1870) in Ivory Coast and Metapolystoma porosissimae du Preez and Kok 1992, from Ptychadena porosissima (Steindachner, 1867) in South Africa. It was therefore likely that many Madagascan polystomes awaited discovery ( Landman et al, 2018 ).…”

Classification of pleurodire polystomes (Platyhelminthes, Monogenea, Polystomatidae) revisited with the description of two new genera from the Australian and Neotropical Realms

“…As an outcome, the first molecular phylogenies on polystomes were published in the early 2000s with Sinnappah et al (2001) , Bentz et al (2001 , 2006) and Verneau et al (2002 , 2009) , providing a phylogenetic framework for discussion of both their evolution since their origin in the Paleozoic period and dispersal in more recent times. Though other publications contributed later to a better understanding of their evolution through time and space ( Badets et al, 2011 ; Héritier et al, 2015 ), molecular phylogenies also proved to be an essential tool to the taxonomy of amphibian polystomes ( Berthier et al, 2014 ; Chaabane et al, 2019 ; Du Preez et al, 2007 , 2010 , 2014 ; Fan et al, 2020 ; Landman et al, 2018 , 2021 ; Raharivololoniaina et al, 2011 ; Yildirimhan et al, 2012 ) as well as chelonian polystomes ( Du Preez et al, 2017 ; Dutton et al, 2021 ; Héritier et al, 2018 ).…”