The Marbled Honeyeater occurs in New Guinea. A survey in the Adelbert Mountains reported that it was common above 1,580 m.
A taxonomic paper comparing Pycnopygius cinereus with P. ixoides describes both as having an olive to dark crown with fine black streaking or scaling, gray to dusky underparts, and no iridescence.
The species account lists forest, forest edges, and secondary growth as habitat, and records fruit and nectar in its diet.
An extinction-risk assessment has not been added yet.