Genetic variation within and among species of Cloacina (Strongyloidea: Cloacinine) from the swamp wallaby, Wallabia bicolor (Marsupialia: Macropodidae)

Molecular characterization of species of Cloacina (Strongyloidea: Cloacininae) from the common wallaroo, Macropus robustus (Marsupialia: Macropodidae) in Australia

“…Previously published ITS sequences of Cloacina atthis and C. clymene (available from GenBank) were also included (Beveridge et al, 2014). The ITS-1 and ITS-2 rDNA sequences of Arundelia dissimilis were used as the outgroup (Shuttleworth et al, 2014). The BI analysis was conducted, employing the Markov Chain Monte Carlo (MCMC) method in Mr Bayes 3.1.2 (Huelsenbeck and Ronquist, 2001;Ronquist and Huelsenbeck, 2003).…”

“…Considering the highly conserved nature of the ITS regions in nematodes (Chilton, 2004;271 Gasser and Newton, 2000) and previous studies utilising the regions to detect potential 272 cryptic species within Cloacina (Chilton et al, 2009;Shuttleworth et al, 2014), it is possible 273 that the nucleotide variation observed in a number of species of Cloacina indicates genetic divergence within species. The existence of cryptic species amongst cloacinine nematodes in macropodid marsupials has been detected previously.…”

“…The most diverse genus within the subfamily is Cloacina, with more than 115 described species (Beveridge, 1998(Beveridge, , 2014Beveridge et al, 2014;. In addition to this morphological diversity, molecular analyses of Cloacina species have revealed extensive genetic variation within the genus, based on the characterization of the first and second internal transcribed spacers (ITS-1 and ITS-2 = ITS) of nuclear ribosomal DNA (rDNA) (Chilton et al, 2009;Shuttleworth et al, 2014). For example, Shuttleworth et al (2014) detected genetic variation within and among nine species of Cloacina from a single host, Wallabia bicolor, suggesting incipient speciation within the species studied.…”

“…In addition to this morphological diversity, molecular analyses of Cloacina species have revealed extensive genetic variation within the genus, based on the characterization of the first and second internal transcribed spacers (ITS-1 and ITS-2 = ITS) of nuclear ribosomal DNA (rDNA) (Chilton et al, 2009;Shuttleworth et al, 2014). For example, Shuttleworth et al (2014) detected genetic variation within and among nine species of Cloacina from a single host, Wallabia bicolor, suggesting incipient speciation within the species studied. Chilton et al (1997) utilised a multilocus electrophoretic approach to explore variation within several species of Cloacina and proposed that some of them represented complexes, comprising morphologically similar but genetically distinct (i.e., cryptic) species.…”

“…The common wallaroo is currently subdivided into four subspecies, three of which are located across the Australian mainland (M. r. robustus along the eastern coast; M. r. erubescens across inland areas; M. r. woodwardi in the tropical north and northwest; Van Dyck and Strahan, 2008). Previous studies investigating genetic variation within the subfamily Cloacininae have found considerable nucleotide variation (Chilton et al, 2009;Shuttleworth et al, 2014;Tan et al 2012), with some evidence suggesting that speciation based upon location may occur within some macropodid hosts (Tan et al, 2012). Given the wide distribution of the common wallaroo and its extensive parasitic diversity, it is possible that speciation of Cloacina species could be occurring within this host.…”