Leaves usually sessile or subsessile, leaves on short axillary shoots often clustered and smaller than leaves on main stems; stipules minute or absent.
Flowers solitary and terminal or apparently axillary, pedunculate or sessile in a whorl of floral leaves and bracts. Sepals 5, glabrous or hairy; the 2 'outer' sepals marginally overlap the 3 'inner' ones. Petals 5, yellow. Stamens few or numerous, surrounding carpels and usually arranged in ± 3 groups or sometimes all on one side of the carpels, occasionally some reduced to staminodes; anthers erect, generally oblong, dehiscing by longitudinal slits or [terminal pores]. Carpels usually 2–5, free or nearly so; ovules usually 2–6 in each carpel; styles filiform.
This genus is under revision. Intermediates occur between some taxa and these complicate the delineation and identification of certain species.
| | Key to the species | |
| 1 | Stamens inserted all around the carpels, but sometimes more numerous on one side; staminodes occasionally present; carpels 1–many | 2 |
| Stamens all on one side of the carpels; usually all stamens fertile or sometimes staminodes present and surrounding the carpels; carpels usually 2 | 25 |
| 2 | Carpels glabrous, usually 1 or 3 or more | 3 |
| Carpels hairy, usually 2 or 3
Back to 1 | 19 |
| 3 | Climbing or trailing shrubs with stems to 4 m long; most leaves more than 15 mm wide | 4 |
| Erect or prostrate shrubs, not climbing; most leaves less than 10 mm wide
Back to 2 | 5 |
| 4 | Leaves tapering at the base, sessile and stem-clasping; margins usually entire | Hibbertia scandens |
| Leaves with lamina obtuse at base, distinctly petiolate; margins toothed
Back to 3 | Hibbertia dentata |
| 5 | Leaves narrow-linear to more or less terete, mostly less than 1 mm wide | 6 |
| Leaves linear to obovate or elliptic, more than 1 mm wide
Back to 3 | 8 |
| 6 | Leaves clustered, margins incurved | 7 |
| Leaves scattered (sometimes appearing clustered owing to growth of short axillary shoots), margins tightly involute
Back to 5 | Hibbertia virgata |
| 7 | Leaves less than 10 mm long; stamens 8–12 | Hibbertia fasciculata |
| Leaves more than 15 mm long; stamens 15–20
Back to 6 | Hibbertia elata |
| 8 | Stamens less than 30 | 9 |
| Stamens more than 30. (The species H. obtusifolia s.str., H. sp. B, H. kaputarensis and H. acuminata may be included under this extremely variable species or complex as Hibbertia obtusifolia s. lat.)
Back to 5 | 15 |
| 9 | Leaves linear-cuneate, cuneate or oblanceolate, folded longitudinally, generally with several prominent teeth on the truncate apex or apex emarginate; plants erect; stamens 10–12 or 15–30; carpel solitary or 3 | 10 |
| Leaves not folded longitudinally, variable in shape and generally entire but if not, then teeth or lobes lateral and plants prostrate; apex variable but not toothed-truncate; plants prostrate or erect; stamens more than 14; carpels more than 1
Back to 8 | 11 |
| 10 | Stamens 10–12; carpel solitary; leaves and stems generally glabrous | Hibbertia monogyna |
| Stamens 15–30; carpels usually 3; leaves and stems glabrous or more often hairy
Back to 9 | Hibbertia circumdans |
| 11 | All sepals silky; leaves mostly more than 30 mm long | Hibbertia saligna |
| Sepals glabrous to hairy but never with all sepals silky; most leaves less than 30 mm long
Back to 9 | 12 |
| 12 | Leaves with length to width ratio of less than 4:1 | 13 |
| Leaves with length to width ratio of more than 4:1
Back to 11 | 14 |
| 13 | All sepals glabrous; leaves with lateral teeth or lobes or leaves less than 6 mm long; plant more or less prostrate; leaves and stems glabrous or occasionally with short hairs | Hibbertia diffusa |
| Outer sepals villous in upper half; leaves generally entire and more than 6 mm long; plant erect; stems and leaves villous with whitish hairs 1–3 mm long
Back to 12 | Hibbertia villosa |
| 14 | Sepals 10–15 mm long; carpels generally 4 | Hibbertia procumbens |
| Sepals 5–6 mm long; carpels usually 3
Back to 12 | Hibbertia linearis |
| 15 | Sepals glabrous, sparsely hairy or margins ciliate | 16 |
| All sepals densely hairy
Back to 8 | 17 |
| 16 | Stems and leaves greyish, shortly tomentose to glabrous; margins of leaves usually recurved | Hibbertia obtusifolia |
| Stems whitish-tomentose, leaves with white hairs towards base, otherwise glabrous except for ciliate margins; leaves more or less flat
Back to 15 | Hibbertia sp. B sensu Harden (1990) |
| 17 | Sepals obtuse to acute; leaves and young stems shortly greyish-tomentose to glabrous | 18 |
| Sepals acuminate; young leaves and stems with scattered long whitish hairs
Back to 15 | Hibbertia acuminata |
| 18 | Sepals rusty- to whitish-tomentose | Hibbertia kaputarensis |
| Sepals greyish-pubescent
Back to 17 | Hibbertia obtusifolia |
| 19 | Leaves more or less oblong to linear or narrow-lanceolate, usually less than 10 mm long and less than 2.5 mm wide, margins recurved or revolute; stems, calyces and leaves glabrous or shortly hairy, hairs mostly simple | 20 |
| Leaves elliptic, oblong or oblanceolate to spathulate, usually more than 10 mm long and more than 2.5 mm wide, more or less flat; stems, calyces and lower surface of leaves shortly stellate-hairy or with long simple hairs
Back to 2 | 23 |
| 20 | Peduncles longer than the leaves | Hibbertia pedunculata |
| Flowers sessile or on obscure peduncles 1–2 mm long
Back to 19 | 21 |
| 21 | Sepals glabrous except for ciliate margins or rarely minutely hairy; staminodes absent | Hibbertia serpyllifolia |
| Sepals densely and conspicuously hairy; staminodes usually present
Back to 20 | 22 |
| 22 | Sepals villous, hairs simple; stamens c. 30 | Hibbertia vestita |
| Sepals velvety to pubescent, hairs stellate; stamens 6–12
Back to 21 | Hibbertia cistoidea |
| 23 | Stamens less than 20; stems, calyces and at least lower surface of leaves densely hairy with short stellate hairs | 24 |
| Stamens more than 20; stems, calyces and leaves pilose with more or less simple or sparsely branched hairs
Back to 19 | Hibbertia marginata |
| 24 | Most leaves more than 25 mm long; stamens 6 | Hibbertia hexandra |
| Leaves generally less than 25 mm long; stamens more than 9
Back to 23 | Hibbertia hermanniifolia |
| 25 | Carpels glabrous; outer surface of sepals glabrous or rarely sparsely hairy | 26 |
| Carpels hairy, sometimes sparsely hairy to glabrescent; outer surface of sepals generally hairy but sometimes glabrous
Back to 1 | 30 |
| 26 | Leaves crowded and clustered; older stems brownish, not polished | Hibbertia fasciculata |
| Leaves scattered; older stems reddish, polished
Back to 25 | 27 |
| 27 | Flowers axillary on peduncles c. 10 mm long | 28 |
| Flowers terminal, ± sessile
Back to 26 | 29 |
| 28 | Stamens 4; leaves mostly <8 mm long | Hibbertia rufa |
| Stamens 6–8; leaves usually >8 mm long
Back to 27 | Hibbertia acicularis |
| 29 | Weak-stemmed plant with trailing stems; stamens 4, filaments fused; form confined to the New England and Gibraltar Ra. districts | Hibbertia rufa |
| Stout-stemmed plant with erect stems; stamens c. 6, filaments not fused; southwards from Sydney district and Blue Mtns
Back to 27 | Hibbertia cistiflora |
| 30 | Flowers pedunculate, peduncles 2–15 mm long | 31 |
| Flowers sessile or almost so
Back to 25 | 39 |
| 31 | Leaves pungent or rarely not pungent, upper surface ± glabrous; sepals glabrous to sparsely hairy, hairs usually ± hooked | Hibbertia acicularis |
| Leaves not pungent, apex acute to obtuse, upper surface distinctly hairy; sepals stellate-hairy or silky
Back to 30 | 32 |
| 32 | Stamens 2–9 (usually 4–6) | 33 |
| Stamens 9 (usually 10–12)
Back to 31 | 34 |
| 33 | Lower surface of leaves ± densely hairy with stellate hairs (rarely mixed stellate and hooked simple hairs on juvenile leaves) | Hibbertia aspera |
| Lower surface of leaves (except midrib and near margins) ± covered with simple hooked hairs, or glabrescent
Back to 32 | Hibbertia empetrifolia |
| 34 | Stamens 9–12; petals <10 mm long | 35 |
| Stamens 12–15; petals >10 mm long
Back to 32 | Hibbertia covenyana |
| 35 | Bracts subtending flowers up to half as long as the calyx | 36 |
| Bracts subtending flowers two-third as long as calyx
Back to 34 | 37 |
| 36 | Lower surface of leaves densely covered with stellate hairs; confined to far South Coast (SC) | Hibbertia notabilis |
| Lower surface of leaves (except midrib and near margins) covered with simple hooked hairs; restricted to the Blue Mtns (CT)
Back to 35 | Hibbertia decumbens |
| 37 | Upper surface of leaves and outer calyx lobes usually hairy with simple, rarely stellate hairs | Hibbertia hirta |
| Upper surface of leaves and outer calyx lobes with simple hairs over stellate hairs
Back to 35 | 38 |
| 38 | Leaves 2.7–7 mm wide; stamens 12; only known from the Gibraltar Ra. (NC) | Hibbertia rhynchocalyx |
| Leaves 1–2.5 mm wide; stamens 6–12; widespread, but not common, not recorded for Gibraltar Ra. (NC CC NT CT NWS)
Back to 37 | Hibbertia cistoidea |
| 39 | Leaves flat or with slightly recurved margins, oblanceolate to oblong, mostly >3 mm wide | 40 |
| Leaves with revolute margins, linear to narrow-oblong or oblanceolate, generally <3 mm wide
Back to 30 | 41 |
| 40 | Sepals densely silky | Hibbertia bracteata |
| Sepals glabrous
Back to 39 | Hibbertia nitida |
| 41 | Leaves and branches with simple hairs, or mostly simple, but with a few stellate hairs also present | 42 |
| Leaves and branches with stellate or short and bristle-like with 1–several arising from a tubercle, sometimes mixed with long simple hairs
Back to 39 | 47 |
| 42 | Leaves with lower surface usually exposed between revolute margin and mid-vein; leaves villous to appressed hairy | 43 |
| Leaves with lower surface not exposed between revolute margin and mid-vein; leaves puberulous to glabrescent
Back to 41 | 45 |
| 43 | Leaves (2.4-)3–4.5(-7.5) mm wide; mid-vein not or scarcely raised | Hibbertia praemorsa |
| Leaves up to 2.4 mm wide; mid-vein depressed or slightly to distinctly raised
Back to 42 | 44 |
| 44 | Leaves c. 1 mm wide; mid-vein depressed or only slightly raised; stamens 8–14 | Hibbertia calycina |
| Leaves 1.1–2.4 mm wide; mid-vein distinctly raised and/or broadened; stamens 6–9
Back to 43 | Hibbertia superans |
| 45 | Ovary puberulous to glabrescent, sometimes almost villous; leaves narrowly triangular to almost linear | Hibbertia puberula |
| Ovary hairy (villose or tomentose); leaves more or less linear
Back to 42 | 46 |
| 46 | Calyx lobes with margin recurved and surface strongly accrescent; ovary tomentose | Hibbertia tenuifolia |
| Calyx lobes more or less flat, margin not recurved, surface scarcely accrescent; ovary villose
Back to 45 | Hibbertia simulans |
| 47 | Leaves mostly narrow-oblanceolate, apex cuneate to emarginate | Hibbertia cistoidea |
| Leaves linear to narrowly lanceolate, apex obtuse to acute
Back to 41 | 48 |
| 48 | Branches and leaves greyish, softly hairy; hairs of branches and leaves with of two lengths, short and long; flowers with tuffs of hairs between petals and stamens | Hibbertia incana |
| Branches and leaves mostly green (a greyish hairy form confined to porphyry and granite areas in NT and NWS); hairs of branches and leaves all short, sometimes mixed with longer simple hairs; flowers lacking tuffs of hairs between petals and stamens
Back to 47 | Hibbertia riparia |
