Transversotrema Witenberg, 1944 (Trematoda: Transversotrematidae) from inshore fishes of Australia: description of a new species and significant range extensions for three congeners

Abstract

Four transversotrematid trematodes are reported from commercial teleost species in Australian waters. Transversotrema hunterae n. sp. is described from three species of Sillago Cuvier (Sillaginidae) from Moreton Bay, south-east Queensland. Molecular characterisation using ITS2 rDNA confirmed this stenoxenic specificity of Transversotrema hunterae n. sp., with identical sequence data from Sillago maculata Quoy & Gaimard, S. analis Whitley and S. ciliata Cuvier. Phylogenetic analysis, based on 28S rDNA data, demonstrates that T. hunterae n. sp. belongs to the 'Transversotrema licinum clade' and is most closely related to Transversotrema licinum Manter, 1970 and T. polynesiae Cribb, Adlard, Bray, Sasal & Cutmore, 2014, with the three species forming a well-supported clade in all analyses. We extend the known host and geographical ranges of three previously described Transversotrema species, T. licinum, T. elegans Hunter, Ingram, Adlard, Bray & Cribb, 2010 and T. espanola Hunter & Cribb, 2012. The new records represent significant range extensions for the three species and permit further examination of the patterns of biogeographical distribution in Australian waters. Host-specificity of Transversotrema species is examined, and the degree to which morphological analysis can inform taxonomic studies of this group is discussed.

Lepocreadiidae Odhner, 1905 and Aephnidiogenidae Yamaguti, 1934 (Digenea: Lepocreadioidea) of fishes from Moreton Bay, Queensland, Australia, with the erection of a new family and genus

“…A single base difference is consistent with the minor geographical variation found between these locations for other trematodes (e.g. Cutmore et al, 2016 ; Brooks et al, 2017 ); however, given that this single base difference (an A to T transversion) is within the in the first 15 bases of the start of the sequence, and that this base position is an A in all other taxa included in the analysis, we predict that the difference in FJ788485 is a sequencing misread. This species has also been reported from the same host in the waters off New Caledonia by Bray & Justine ( 2012 ).…”

“…Considering the recognition that Gibsonivermis warrants a separate family-level status within the Lepocreadioidea, the phylogenetic status of these other distinctive, apparent “southern endemics”, is of great interest. Since 1999, only records of opecoelids and transversotrematids have been added to the known sillaginid digenean fauna (Aken’Ova, 2003 ; Aken’Ova et al, 2008 ; Cutmore et al, 2016 ).…”

Lepotrema Ozaki, 1932 (Lepocreadiidae: Digenea) from Indo-Pacific fishes, with the description of eight new species, characterised by morphometric and molecular features

“…In the face of this somewhat conflicting information, we propose a conservative approach, interpreting the forms from H. polylepis as a single species that demonstrates geographical genetic variation. This approach (interpreting low-level genetic differences in worms from the same or very similar hosts over geographic range as intra-specific variation) has been adopted for several trematode taxa of late [Cryptogonimidae: Miller et al ( 2010b ); Faustulidae: Diaz et al ( 2013 ); Fellodistomidae: Downie et al ( 2011 ); Monorchiidae: McNamara et al ( 2014 ); Transversotrematidae: Cutmore et al ( 2016 )] although of these, only the study of the Monorchiidae incorporated both ITS2 and cox 1 sequence data. Ultimately, we think that we do not yet know enough about the nature of the distribution of trematodes in the Indo-Pacific to be able to reliably interpret circumstances such as these.…”

An Anomalous Phylogenetic Position for Deraiotrema platacis Machida, 1982 (Lepocreadiidae) from Platax pinnatus on the Great Barrier Reef

“…The protocols for molecular analysis were as described by Cutmore et al [5] and Wee et al [6]. The complete ITS2 rDNA region was amplified and sequenced using the primers 3S [7] and ITS2.2 [8], the partial D1-D3 28S rDNA region using LSU5 [9], 300F [10], ECD2 [11] and 1500R [12] and the partial cox1 mtDNA region using Dig_cox1Fa [6] and Dig_cox1R [6].…”