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Swainsona maccullochiana F.Muell.
Ashburton Pea

Fragm. 7:25-26 (1869)
Conservation Code
Not threatened
Naturalised Status
Native to Western Australia
Name Status

Erect, single-stemmed annual, herb, (0.2-)0.5-3 m high. Fl. purple-red/purple-blue-pink, Jul to Oct. Loamy & gravelly soils. Low-lying moist areas, near watercourses.

Grazyna Paczkowska, Descriptive Catalogue, 5 August 1996

Scientific Description

Genus Swainsona. Form erect. Habit herb. Stems Indumentum hairy, Pustules or glands absent, Striation (stems ribbed) striate, Cross section terete, Spiny on any part of plant not spiny. Leaves or phylloclades Presence clearly present, Position alternate, Leaves compound, Leaves or phylloclade continuous with stem not continuous with stem, Cross section of leaf or leaflet flat with flat margins, Margins of leaf or leaflet entire, Tuberculate tubercles absent, Pustules or glands absent. Length Leaf length 95-320. Width (entire leaves only) Leaf width NaN (?). Scale leaves length mm long NaN (?). Leaflets Number more than three, Number of leaflets (if more than three) 15-23, Arrangement pinnately arranged. Terminal leaflet Presence present, Stalk stalked. Indumentum Presence hairy, Type simple. Stipules Presence present and persistent to older leaves, Glands without glands, Ribs ribless. Length Stipule length 10-11.5. Bracteoles Presence present and persistent, Indumentum hairy, Striation not striate. Length Bracteole length 2-2.5. Pedicel Presence present, Indumentum hairy. Length Pedicel length 4-6. Calyx Pustules or glands absent, Ribs ribless, Enlarged in fruit not accrescent. Length Calyx length 9-14.5. Indumentum Presence hairy, Type with simple hairs. Corolla Colour patterning multicoloured, Colour (when multicoloured - choose one colour) pink, red, purple or blue, Colour (when multicoloured - choose a second colour) pink, red, purple or blue, Petal claws ( the narrow base of the petals present. Length Corolla length 25-32. Indumentum Presence absent. Standard Indumentum glabrous, Auricles not auriculate. Length Standard length 24-30. Wings Auricles auriculate. Length Wing length 16-28. Keel Auricles auriculate, Indumentum glabrous, Beak not beaked. Length Keel length 25-32. Stamens Number ten. Anthers anther length 1.2-1.9, Position at two different levels (filaments alternately long and short). Filaments Fusion united in an open sheath with one free stamen. Length Filament length 16-26. Ovary Placement stipitate. Indumentum Presence hairy or glandular. Style Indumentum hairy or glandular towards the base, Bearded ( with a tuft of hairs at apex ) bearded (with a tuft of hairs at apex), Apex terete. Length Style length 20-34.5. Fruit Type dehiscent (a pod or follicle), Constriction not constricted between the seeds, Compression round in cross-section, Placement stipitate. Length Fruit length 30-35. Width Fruit width 9-12. Indumentum Presence hairy, Indumentum type with simple hairs. Flowering time July, August, September or October. Distribution Botanical Province Eremaean, IBRA Bioregion Pilbara or Gascoyne.

C. Hollister and K.R. Thiele, 17 April 2024


IBRA Regions
Carnarvon, Gascoyne, Pilbara.
IBRA Subregions
Ashburton, Augustus, Chichester, Fortescue, Hamersley, Roebourne, Wooramel.
Local Government Areas (LGAs)
Ashburton, Carnarvon, East Pilbara, Karratha, Meekatharra, Upper Gascoyne.