Abstract
Adult blood flukes of the genera
Hapalotrema
Looss, 1899 and
Learedius
Price, 1934 were collected from turtles off Queensland and the Hawaiian Islands. Specimens were identified as
Hapalotrema pambanensis
Mehrotra, 1973,
H. synorchis
Luhman, 1935,
H. postorchis
Rao, 1976 and
Learedius learedi
Price, 1934 on the basis of morphology. No major morphological differences were found between specimens from this study and previously published descriptions. DNA was also extracted and sequences obtained using custom spirorchiid-specific primers for the ITS2 and 28S rDNA regions, in order to confirm species identification and investigate phylogenetic relationships. Intraspecific genetic variation was generally low. However the ITS2 region of
H. postorchis
and to a lesser extent that of
L. learedi
showed considerable variation between specimens from the Pacific and Atlantic oceans. Further studies will be required to determine whether this variation should be considered inter- or intra-specific. Maximum likelihood phylogenetic analyses were completed for both sequenced genes.
Learedius learedi
was unequivocally nested among species of
Hapalotrema
, suggesting that the status of the genus
Learedius
may need to be reassessed.