A regional examination of the mistletoe host species inventory

Downey (1998) collated an inventory of mistletoe host species based on herbaria records for every aerial mistletoe species (families Loranthaceae and Viscaceae) in Australia. In this paper the representative nature of those host lists is examined in an extensive field survey of mistletoes and their host species in south-eastern New South Wales (including Australian Capital Territory). Four new host species not in the 1998 inventory, and eight new mistletoe-host combinations (i.e. a previously recorded host but not for that particular mistletoe species) were collected. These new records were distributed throughout the survey area. Interestingly, these new host-mistletoe combinations were for
mistletoe species that were well represented in the national inventory (i.e. with many herbarium collections and numerous host species). The initial inventory was incomplete, at least for south-eastern New South Wales, indicating the need for (i) more targeted surveys similar to this one, and/or (ii) regular updates of the host inventory based on voucher specimens. A possible reason why information on host-mistletoe combinations is incomplete may be that such combinations may be dynamic (i.e. mistletoe species may be expanding their suite of potential hosts, either fortuitously or as result of evolutionary pressures).