SPECIES OF MEDIORHYNCHUS (ACANTHOCEPHALA: GIGANTORHYNCHIDAE) IN AUSTRALIAN BIRDS WITH THE DESCRIPTION OF MEDIORHYNCHUS COLLURICINCLAE N. SP

Four species of Mediorhynchus are identified from Australian birds. New locality records are given for Mediorhynchus alecturae (Johnston and Mawson, 1947) Golvan, 1962 and new host and locality records for M. corcoracis Johnston and Edmonds, 1951. Mediorhychus grandis has been reported from Australian hosts, but this record could not be verified. Two females from Acanthogenys rufogularis and the anterior portion of a single female from a “gull” had characters of proboscis armature, lemnisci, and eggs that precluded them being assigned to any of the presently known species of Mediorhynchus. Mediorhynchus colluricinclae n. sp. was found in pomatostomatids from South Australian localities. A high degree of host specificity is recorded for M. corcoracis and M. colluricinclae. Selection of specific dietary items may be one filter that influences the degree of host specificity encountered.