Citation: R. Br. ex J. Knight, Cult. Proteaceae 120 (1809).

Derivation: After Charles Francis Greville, 1749-1809, horticulturalist and Vice-President of the Royal Society of London.

Synonymy: Not Applicable

Common name: Grevilleas or spider-flowers.

Description:
Shrubs or trees, sometimes suckering; indumentum of T-shaped eglandular hairs, rarely simple and erect; leaves petiolate or sessile, simple or compound, the blade or segments entire or lobed or toothed, upper side differing from the lower in venation and persistence of pubescence, margins recurved, rarely (Grevillea nematophylla) subterete, obscurely grooved and glabrous.

Inflorescence terminal, rarely axillary, racemes of flowers arranged in pairs, sometimes several in panicles, sometimes umbelliform through reduction of the rhachis, not developing in an involucre of bracts; flowers bisexual, pedicellate; perianth in bud irregular or regular, with the tube cylindrical, curved below the limb, often greatly, or (outside S.Aust.) straight, the segments at anthesis, through expansion of the pistil, splitting apart equally or fully down one side only; anthers all perfect, ovate, sessile in the limb, the connective not produced beyond the apex; hypogynous glands united into a single semi-annular or semi-circular gland, rarely completely surrounding the ovary or (outside S.Aust.) absent; ovary short- or long-stipitate, 2-ovulate, style elongating faster than the perianth in bud, splitting the perianth tube but held in the limb and so arched to one side of it, finally breaking free, style-end dilated gradually or abruptly into a pollen-presenter which is either an erect cone or an oblique or lateral circular or cuneate-truncate disc bearing the stigma on a short central protuberance.

Fruit a follicle, the concave valves thinly woody, opening down one side only, rarely (outside S.Aust.) woody and opening into 2 valves, with style persisting or only the base remaining; seeds 1 or 2, flat or fusiform when young, finally flat, orbicular or oblong, surrounded by a narrow membranous wing or shortly winged at one end only, or (outside S.Aust.) entirely wingless.

Distribution:  About 250 species throughout Australia; a few species in New Caledonia, New Guinea and the Celebes. Many species are grown in gardens as ornamentals; the silky oak, Grevillea robusta Cunn., a handsome tree with large bipinnatisect leaves and conspicuous racemes of golden flowers, is commonly planted.

Biology: Owing to the ready dehiscence of the fruits, mature seeds have not been seen for most species. Young seeds have been seen for a number of these.

Taxonomic notes: Species of Grevillea in South Australia belong to four informal groups, defined below. These groups are mentioned in the key. GROUP A:

Key to Species:

1. Leaves either consistently divided (pinnatipartite) or lobed or toothed (predominantly Group A)
2. Leaves lobed or toothed, not divided almost to the midrib into linear segments
3. Flower-subtending bracts c. 1.5-4 mm long, more or less persistent at flowering; style abruptly expanded into the pollen-presenter; indumentum on branchlets, leaves, rhachis, perianth and ovary of raised curled hairs	Grevillea aquifolium 1.
3. Flower-subtending bracts c. 1 mm long, deciduous at bud stage; style on dorsal side continuous with the pollen-presenter; indumentum on branchlets, leaves, rhachis, perianth and ovary of appressed straight hairs	Grevillea ilicifolia 4.
2. Leaves pinnatipartite. [Note: if character combinations other than those present at couplet 4, go to couplet 7.]
4. Final segments of leaves 3-18, usually over 7; racemes 1-sided, elongated, the rhachis 1.5-5.5 cm long; pedicel 0-3.8 mm long; ovary hirsute; style 16-30 mm long
5. Leaves with petiole 1.5-5 cm long, final segments 0.5-3.5 cm long, the midrib narrower than the blade either side below, hardly prominent above; perianth green. [Go to couplet 3.]
5. Leaves with petiole 0.5-1 cm long, final segments 0.7-1.5 cm long, the midrib much broader than the blade on either side below, prominently raised above; perianth red	Grevillea treueriana 5.
4. Final segments 3-9; racemes umbelliform, the rhachis 0.6-2 cm long; pedicel 6-9 mm long; ovary glabrous; style 1.7-12 mm long
6. Leaf segments narrow-linear, needle-like, c. 0.7 mm wide; flowers white; perianth 3-3.5 mm long, splitting into 4 free segments; pollen-presenter an erect cone; fruit coarsely muricate-rugose	Grevillea biternata 2.
6. Leaf segments linear, 1-2 mm wide; flowers pink; perianth 15-24 mm long, splitting fully down one side only; pollen-presenter an oblique disc; fruit smooth	Grevillea huegelii 3.
1. Leaves entire or rarely a few on a branch pinnatipartite
7. At least the majority of leaves on a branch longer than 9.5 cm (Group B)
8. Leaves linear, 3-6 mm wide, with 5-13 longitudinal veins below	Grevillea striata 11.
8. Leaves narrow-linear, 0.9-2.6 mm wide, with no prominent veins below but subterete or with 2 distinct or fine longitudinal grooves below
9. Leaves subterete, with 1 or 2 obscure longitudinal grooves, with no obvious midrib; style 3.5-5.5 mm long; pollen-presenter an erect cone	Grevillea nematophylla 8.
9. Leaves flat, with 2 prominent fine longitudinal grooves between the midrib and margins on the lower side; style 5-20 mm long; pollen-presenter an oblique rarely almost horizontal disc
10. Leaf mucro hooked; style 5-6.5 mm long (straightened); fruit greatly compressed, with style lateral, broken down to the base, reflexed	Grevillea stenobotrya 10.
10. Leaf mucro straight; style 9-20 mm long (straightened); fruit never with above character combination
11. Inflorescences umbelliform, with 10-20 or fewer flowers, rhachis 0.4-0.7 cm long; perianth pink; ovary and fruit glabrous	Grevillea umbellifera 12.
11. Inflorescences elongated, with 15-200 flowers, rhachis 5-26 cm long; perianth white to orange.; ovary hirsute; fruit pubescent
12. Leaves 4-15 cm long; indumentum on branchlets, rhachis, pedicels and perianth externally appressed- pubescent; flowers white; perianth 2.5-3.5 mm long; style 9-13 mm long (straightened); fruit slightly compressed	Grevillea pterosperma 9.
12. Leaves 6-30 cm long; indumentum on branchlets, rhachis, pedicels and perianth externally woolly- tomentose; flowers yellow to orange; perianth 6.5-10 mm long; style 16-20 mm long (straightened); fruit greatly compressed
13. Leaves mid-green to greenish-grey; racemes dense-flowered, with the rhachises towards the base 3.5-6 mm diam.; pedicel 3-4 mm long; pollen-presenter an almost horizontal disc; fruit on a short stout stipe	Grevillea eriostachya 6.
13. Leaves green-yellow, rarely greyish-green; racemes more open, with the rhachises towards the base 2-3 mm diam.; pedicel 8-22 mm; pollen-presenter an oblique disc; fruit on a long slender stipe	Grevillea juncifolia 7.
7. All or the majority of the leaves on a branch less than 9.5 cm long
14. Racemes with c. 100-200 yellow to orange flowers, with rhachis 14-26 cm long, towards the base of the apical raceme 3.5-6 mm diam.; fruit greatly ccompressed, inserted laterally on and perpendicular to a short stout stipe (Group B)	Grevillea eriostachya 6.
14. Racemes with 1-42 white, pink or red flowers, sometimes with a yellowish limb, with rhachis 0.05-3 cm long, towards the base less than c. 1.5 mm diam.; fruit hardly compressed, vertically inserted if sometimes sublaterally on the stipe
15. Pistil glabrous, except sometimes for a few hairs or papillae behind the pollen-presenter (predominantly Group C)
16. Leaves narrow-linear to linear, with 2 narrow persistently pubescent grooves below between the rigid recurved margins and midrib
17. Branchlets appressed-pubescent, with a glabrous rib decurrent from each leaf; leaves widely spreading; perianth 2.6-4 mm long, splitting into 4 free segments	Grevillea parviflora 15.
17. Branchlets with tomentum obscuring a fine rib decurrent from each leaf; leaves more or less erect; perianth 5.5-22 mm long, splitting down one side only
18. Leaves 4-15 cm X 1.5-2.6 mm, with venation obscure above; racemes umbelliform, rhachis 0.4-0.7 cm long; pedicel 6-14 mm long; perianth 15-22 mm long; style 10-16 mm long (Group B)	Grevillea umbellifera 12.
18. Leaves 2.5-7 cm X 1-1.2 mm, with several fine longitudinal veins above; racemes elongated, rhachis 2-3 cm long; pedicel 2-3.5 mm long; perianth 5.5-7.5 mm long; style 4 mm long	Grevillea parallelinervis 14.
16. Leaves broad-obovate to narrow-oblong, or linear through the revolution of the margins on drying, often also obscuring the tomentose lower surface
19. Branchlets appressed-tomentose, with 3 glabrous ribs decurrent from each leaf; upper side of leaves with 2 or 3 parallel veins inside each margin, the connecting reticulate venation obscure; torus horizontal; perianth pink, splitting into 4 free segments; style displaced to one side of the segments, pollen-presenter an oblique disc	Grevillea quinquenervis 17.
19. Branchlets lacking prominent ribs; upper side of leaves with obscure or pinnate-reticulate venation; torus oblique; perianth tube red at least in the lower half, splitting fully down one side only; style erect above the perianth, pollen-presenter more or less lateral
20. Branchlets, pedicel and perianth externally raised-tomentose; leaves minutely tuberculate, with yellow pinnate nerves above; racemes with 6-42 flowers, rhachis 1.4-4.5 cm long; perianth red, with yellow- green limb; style 4-6 mm long, pollen-presenter truncate-cuneate	Grevillea aspera 13.
20. Branchlets, pedicel and perianth externally appressed-pubescent; leaves smooth, with obscure venation above; racemes with 1-4 flowers, rhachis 0.1-0.25 cm long; perianth red throughout; style 6-6.5 mm long, pollen-presenter circular	Grevillea pauciflora 16.
15. Pistil hirsute, at least on the gynophore (Group D)
21. Leaves smooth, glabrous above and below except rarely for a few scattered hairs below (obscured by the recurved margins); rhachis, pedicel and perianth externally glabrous, glaucous; perianth red, with the limb recurved to the level of the ovary (almost to the base of the tube); gland circular; ovary glabrous	Grevillea rosmarinifolia 21.
21. Leaves glabrescent, minutely to prominently tuberculate, persistently tomentose below (but often obscured by the recurved margins); rhachis, pedicel and perianth externally pubescent; perianth red, sometimes with a cream limb, the limb recurved to halfway down the tube; gland semi-circular; ovary hirsute
22. Leaves terete, rarely ovate, thick up to the obtuse apex, 0.2-1.2 cm long, mucro 0.2-0.3 mm long; perianth red throughout; style coarsely raised-brown-tomentose throughout; branchlets more or less persistently raised-tomentose, smooth when glabrescent	Grevillea muricata 19.
22. Leaves linear-subulate to elliptic, flat, thin towards the acute apex; perianth red, with a cream limb; style with a raised white pubescence confined to the base or throughout
23. Branchlets with lateral shoots sporadic, usually elongated, smooth when glabrescent; leaves linear to elliptic, 0.2-3.5 cm long, with minute tubercles 0.01-0.05 rarely to 0.06 mm high, mucro 0.5-2 mm long; perianth tube sparsely tomentose	Grevillea lavandulacea 18.
23. Branchlets with short shoots in almost every axil at flowering time, tuberculate like the leaves when glabrescent; leaves linear to subulate, rarely narrow-ovate, 0.2-0.8 cm long, with prominent tubercles 0.05-0.1 mm high, mucro 0.2-0.45 rarely to 0.6 m long; perianth tube glabrous or with a few very short hairs	Grevillea rogersii 20.

Author: Not yet available