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Eucalyptus mannensis subsp. vespertina

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Eucalyptus | Symphyomyrtus | Bisectae | Destitutae | Micrantherae | Bakerianae

Eucalyptus mannensis subsp. vespertina L.A.S.Johnson & K.D.Hill, Telopea 4: 600–1 (1992).

T: Western Australia: 12km W of road from 'Coburn' to 'Hamelin', 8 Oct. 1975, D.F.Blaxell W75/101 & M.I.H.Brooker; holo: NSW; iso: CANB, PERTH.
Mallee or a straggly tree, to 10 m tall. Forming a lignotuber.
Bark usually rough for up to 4 m of trunk, sometimes extending to ca 8 cm diameter branches, grey-brown, flaky and fibrous, smooth above, grey to white or pale orange.
Branchlets lacking oil glands in the pith.
Juvenile growth (coppice or field seedlings to 50 cm): not seen.
Adult leaves
alternate, petioles 0.5–2 cm long; blade narrowly lanceolate to linear, (6.5)7–14 cm long, 0.5–1.5 cm wide, base tapering to petiole, apex finely pointed, concolorous, usually dull, green to bluish green, side-veins greater than 45° to midrib, densely reticulate, intramarginal vein close to margin, oil glands conspicuously intersectional.
Inflorescence axillary unbranched, peduncles 0.3–1 cm long, buds 7, 9 or 11, pedicellate (pedicels 0.1–0.4 cm long). Mature buds ovoid to more or less fusiform (0.6–0.8 cm long, 0.35–0.5 cm wide), scar present, operculum conical (rarely with a short beak), a few outer stamens erect, inner inflexed, anthers oblong to reniform (wider than long), versatile, sub-basifixed, dehiscing by short oblique slits, style long, arising between three prominent lobes on the ovary roof, stigma blunt, locules 3, the placentae each with 4 vertical ovule rows, ovary roof 3-lobed at the style base with the line of each septum bisecting a lobe. Flowers creamy white.
Fruit pedicellate (0.1–0.4 cm long), hemispherical to slightly truncate-globose, 0.3–0.8 cm long, 0.5–0.9 cm wide, disc usually level but may be slightly raised or even obliquely descending, valves 3, exserted, each valve with an apical notch often containing part of the base of the style.
Seeds dark brownish grey, 1–2.5 mm long, flattened-ovoid, dorsal surface shallowly reticulate, hilum ventral.

Cultivated seedlings (measured at ca node 10): cotyledons Y-shaped (bisected); stems rounded in cross-section; leaves always petiolate, opposite for 4–7 nodes then alternate, narrowly lanceolate, 6–10 cm long, 1–1.5 cm wide, dull green to grey-green.
Flowering Time

Flowering has been recorded in January, April, May and November.

Eucalyptus mannensis is a small to large mallee species scattered and widespread from central Australia, south of the Everard Range in South Australia and west to the Indian Ocean, usually on sandy plains. The bark is rough and the adult leaves are glossy green, with numerous oil glands.

Eucalyptus mannensis belongs in Eucalyptus subgenus Symphyomyrtus section Bisectae subsection Destitutae because buds have two opercula, cotyledons are Y-shaped and branchlets lack oil glands in the pith. Within this subsection E. mannensis is closely related to only three other species, E. micranthera (in Western Australia from near Esperance), E. bakeri (from northern New South Wales and southern Queensland) and E. jutsonii (in Western Australia from north of Kalgoorlie and near Morowa), all of which have a peculiar three-lobed ovary roof in which the base of the style is inserted, and leaves with conspicuous intersectional oil glands.

In its natural distribution E. mannensis is not likely to be confused with any other species because of its glossy green leaves with conspicuous irregular intersectional oil glands, thick-rimmed fruit with exserted "valves" that are minutely three-partite at the tips.

There are two subspecies:

E. mannensis subsp. mannensis
Occurs over the major part of the distribution of the species, i.e. from east of Shark Bay in Western Australia  to central Australia. Subsp. mannensis has very glossy adult leaves.

E. mannensis subsp. vespertina
Restricted to sub-coastal Western Australia from Murchison River to Shark Bay area. Subsp. vespertina is weakly distinguished by predominantly narrower adult leaves ( 0.5-1.5 cm wide in subsp. vespertina, 0.7-2.5 cm wide in subsp. mannensis) which are at first dull, blue-green and mature to glossy green.
Origin of Name
Eucalyptus mannensis: referring to the Mann Range in northern South Australia.

subsp. vespertina: Latin vesper, western, referring to the far western distribution of the subspecies.
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