Grevillea burrowa Molyneux & Forrester

Burrowa Grevillea

Muelleria 34: 47-54 (2015) APNI

Taxonomic status:Accepted

Occurrence status:Endemic

Establishment means:Native

Threat status:Victoria: vulnerable (v)

Spreading shrub 1.5–4(–6) m high, 2–4(–7) wide. Branchlets densely subsericeous. Leaves entire, oblong, ovate to ovate-elliptic to broadly so, (25–)65-80(–110) mm long, 25–35(–55) mm wide; upper surface initially sparsely sericeous, soon glabrous; margins recurved; lower surface densely white sericeous or occasionally subsericeous, reticulum evident or absent. Conflorescences usually terminal or axillary, declined, decurved, simple to 3-branched. Primary peduncles (0–)2–12 mm long, densely subsericeous; floral rachises (10–)12–20(–32) mm long. Limb of flower buds usually with subpyramidal face or occasionally obtuse in some flowers; flower buds reflexed at or less than 90 degrees to rachis. Limb-segments of tepals (mature pre-anthesis flowers) not or slightly keeled along external midline. Dorsal tepals 25–28 mm long. Perianth outer surface (below limb) red-pink; inner surface bearded. Pistil 20-24 mm long, ovary stipitate, with or without scattered, minute, simple, patent hairs, style pink-red; face of pollen presenter concurrent with style, flat or marginally concave. Fruits glabrous or with simple, minute, patent hairs, soon deciduous. Flowers late Aug.- Jan., and sporadically in early autumn.

Montane dry woodland and rocky outcrop shrubland.

Apparently endemic to the Burrowa Plateau in north-eastern Victoria, where it is currently known by two populations, c. 3 kms apart. Recently segregated from the Grevillea oxyantha species complex. Its closest affinity appears to be with G. oxyantha subsp. ecarinata (which is found in NSW), based on the following shared characters. Leaves are similar in shape and size, with the indumentum of the lower surface sericeous or subsericeous or occasionally subtomentose in subsp. G. oxyantha subsp. ecarinata (the hairs are straight, but are never curled or curved as in G. oxyantha subsp. oxyantha, which is found in NSW, ACT). Floral rachises are longer than in G. oxyantha subsp. oxyantha, the limb of immature flower buds is less acute than in G. oxyantha subsp. oxyantha, and the limb-segments of tepals are not or only slightly keeled (pronounced longitudinal keel in G. oxyantha subsp. oxyantha). Immature flower buds show none or only some reflexing > 90 degrees (strongly reflexed at > 90 degrees in G. oxyantha subsp. oxyantha).

Grevillea burrowa differs from G. oxyantha subsp. ecarinata (a variable taxon) mainly in having on average shorter floral rachises and correspondingly fewer flowers per unit conflorescence (variable in same population), greater percentage of unbranched conflorescences, juvenile flower buds reflexing to c. 90 degrees (to or > 90 degrees in G. oxyantha subsp. ecarinata), purpotedly broader perianth tubes, and in having occasional hairs on the ovary. Molyneux & Forrester (2015) do not indicate whether the hairy ovary character is constant, or variable. The hairy ovary character is shared with G. victoriae subsp. brindabella, however, in that taxon some plants in the same population have hairs on the ovary, and other plants have glabrous ovaries. Recently, hairy ovaries have also been observed in G. callichlaena. Examination of cultivated plants of G. burrowa at the Royal Botanic Gardens in Melbourne shows that individual plants have some conflorescences that have flowers with hairy ovaries, and other conflorescences in which the flowers lack hairs on the ovary. Grevillea burrowa is probably better treated as a subspecies of G. oxyantha.

Created by: Val Stajsic, 2016-09-06
Updated by: Val Stajsic, 2018-03-14
 
References

Molyneux, W.M. & Forrester, S.G. (2015). A new species of Grevillea burrowa (Proteaceae) from the Burrowa-Pine Mountain National Park, North Eastern Victoria, Muelleria 34: 47–54.

Hero image
life Life
kingdom Plantae
phylum Tracheophyta
superorder Proteanae
order Proteales
family Proteaceae
genus Grevillea
Higher taxa