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Eucalyptus archeri Maiden & Blakely, Crit. Revis. Eucalyptus
8: 58 (1929).
T: Western Mts, Tas., Jan. 1848, W.H.Archer; holo: NSW; iso:
CANB.
Small tree or mallee to 12 m tall. Forming a lignotuber.
Bark smooth, grey-green, grey, pinkish, white or brown, sometimes
with horizontal black scars.
Juvenile growth (coppice or field seedlings to 50 cm):
stem rounded or square in cross-section, warty or smooth; juvenile
leaves opposite, sessile and orbicular for at least 25 nodes, becoming
alternate, petiolate, orbicular to ovate, 1.3-3.9 cm long, 0.9-3.2
cm wide, margin crenulate or entire, green or grey-green (only tip
growth and newly expanded juvenile leaves glaucous).
Adult leaves alternate, petiole 0.8-2.2 cm long; blade lanceolate
to elliptical, 4-9 cm long, 0.9-3 cm wide, flat (rarely undulate),
base tapering evenly to petiole, margin entire, concolorous or slightly
discolorous, glossy, green to grey-green, side-veins
greater than 45° to midrib,
densely to very densely reticulate, intramarginal vein parallel to
and well removed from margin, oil glands scattered, intersectional.
Inflorescences axillary unbranched, peduncles 0.1-0.7 cm long;
buds 3, shortly pedicellate or sessile (often only central bud pedicellate),
oblong to ovoid to clavate, green, usually slightly angular, scar
present, operculum conical, rounded or slightly beaked, stamens inflexed,
anthers cuboid to oblong, versatile, dorsifixed, dehiscing by longitudinal
slits (non-confluent), style short or long, locules 3 or 4, the placentae
each with 4 vertical ovule rows (sometimes with an incomplete fifth
row); flowers white.
Fruit sessile to shortly pedicellate, cylindrical, barrel-shaped,
obconical or hemispherical, 0.5-0.8 cm wide, disc descending, valves
3 or 4, near rim level or enclosed.
Seed dark brown or blackish, 1.2-2 mm long, ovoid or flattened-ovoid,
often pointed at one end, usually lacunose, dorsal surface smooth
or shallowly pitted, hilum ventral.
Cultivated seedlings (measured at ca node 10): cotyledons bilobed;
stems usually squared in cross-section, sometimes slightly winged,
often slightly warty; leaves opposite and sessile for many nodes,
orbicular to ovate, 1.5-2.7 cm long, 1.2-2.5 cm wide, base amplexicaul
to rounded, apex rounded, glaucous weathering to green.
NOTES
Eucalyptus archeri (after William H. Archer, 1829-1874. For
some years Archer was secretary of the Royal Society of Tasmania,
as well as being a fellow of the Royal Society and the Linnean Society.
He was a keen collector of botanical specimens and in 1848 collected
specimens from the Western Mountains of Tasmania which eventually
became the type material for the name Eucalyptus archeri).
A small tree endemic to Tasmania, E. archeri is distinguished
from the related E. gunnii
which has glaucous buds and fruits. From other 3-budded species in
Tasmania it is distinguished by the combination of cupular fruit and
orbicular to cordate juvenile leaves.
Eucalyptus
archeri belongs in Eucalyptus
subgenus Symphyomyrtus section Maidenaria, a large group
of species more or less restricted to south-eastern Australia, characterized
by bilobed cotyledons, simple axillary inflorescences, buds with two
opercula, stamens with versatile anthers and flattened seeds with
a ventral hilum. Within this section, E.
archeri, with 9 other species, forms series Orbiculares
having orbicular to cordate juvenile leaves opposite for many nodes,
a grey-green to green crown, and buds in 3s. Series Orbiculares
is confined to far south-eastern New South Wales, eastern Victoria
and Tasmania.
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