Philocryptica is a monotypic genus of moths belonging to the subfamily Tortricinae of the family Tortricidae.

[7] George Hudson discussed and illustrated this species in his 1928 book The butterflies and moths of New Zealand.

Palpi rather short, obliquely ascending, second joint with tolerably appressed scales.

The fore-wings are broad with the costa very strongly and evenly arched and the termen rounded; in female brownish-ochreous with dull blue, deep red, and yellow-brown markings; there is a broad horizontal dull blue band along the costa from the base to nearly 1⁄2 and a very large tornal blotch extending along the termen almost as far as the apex; a broad, very oblique deep red bar extends from the costa at about 3 to the termen below the apex where it joins the tornal blotch; there are several small yellow-brown marks on the dorsum, on the discal edges of the costal band and tornal blotch, and on the pale apical patch; the cilia are blackish.

In the male the fore-wings are almost entirely overspread with dull bluish-black; the red costal bar is very much reduced and margined with black, there are several other indistinct black markings on the costa and in the dise, and a distinct pinkish-ochreous apical patch.[8]P.

[9] The colouration of adult moths ensure the species is well camouflaged when resting against the dead or dying leaves of its host plant.

[10] P. polypodii inhabits native forest where the larval host of the moth, Pyrrosia eleagnifolia, is present.

[7] At the final stage of larval development, the older larvae create a large blotch mine in which it pupates.

[9] The larva will exude a silken thread if shaken from the leaf which they then use to return to their host.

[7] When the adult moth is disturbed it runs about in an unpredictable directions adding pauses in its activity.

[7] It is assumed that insects, spiders and birds feed on the adult moths of this species.