Petenaea cordata (from northern Central America) was first described in Elaeocarpaceae and later placed in Tiliaceae, but most authors have been uncertain about its familial affinities.

It was considered a taxon incertae sedis in the Angiosperm Phylogeny Group classification (APG III).

Molecular analyses based on a recent collection from Guatemala indicate a distant, weakly supported sister-group relationship to the African genus Gerrardina (Gerrardinaceae; Huerteales).

Leaves minutely stipulate; petioles 5–11 cm, densely short villous, red; blades 8.5-15.5 × 6.5-14.5 cm, chartaceous, densely villous below, glabrescent above, turning red with age, palmately veined at base with 5-7 primary veins, the secondary venation reticulate, the base broadly cordate, the margins minutely denticulate, the apices acute to broadly short-acuminate.

Flowers with the sepals c. 4 mm, valvate, lanceolate, attenuate from the base to the apex, reflexed, reddish pink, the base bearing 2-3 obovoid subsessile glands, and densely villous with hairs c. 2 mm, moniliform, pink; petals absent; disc annular, glandular; stamens 8-12, glabrous, the anthers yellow, opening by an apical pore-like slit; ovary superior, sessile, tomentose; style slender; stigma discoid.