Muellerina flexialabastra, common name Hoop pine mistletoe, is a hemiparasitic aerial shrub in the family Loranthaceae.

[3] The inflorescence is a terminal raceme off a central axis, and the pink to red tubular flowers occur in strongly reflexed, decussate pairs with a central sessile flower.

[3] The main host on which M. flexialabastra grows is Hoop pine (Araucaria cunninghamii).

[3] An inventory of host plants for Muellerina flexialabastra is given by Downey.

[3] The species was first described by Paul Downey and Carol Wilson in 2004 as Muellerina flexialabastra.