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Eucalyptus annuliformis Grayling & Brooker, Nuytsia 8: 214 (1992).
T: SE of Dandaragan (30°49'S,
115°47'E),
10 June 1986, M.I.H.Brooker 9351, A.H.Popplewell & B.A.Rockel;
holo: PERTH; iso: CANB, MEL, NSW.
Mallee to 3 m tall. Forming a lignotuber.
Bark smooth throughout, greyish.
Branchlets lacking oil glands
in the pith.
Juvenile growth (coppice or field seedlings to 50 cm):
juvenile leaves always petiolate, alternate, elliptical to broadly
ovate, 5-7 cm long, 2-3.5 cm wide, dull, green.
Adult leaves alternate, petioles 1-1.5 cm long; blade elliptical
to broadly lanceolate, 4-6.5 cm long, 1-1.7 cm wide, base tapering
to petiole, margin entire, apex acute, concolorous, dull, green, side-veins
usually greater than 45° to midrib or sometimes acute, reticulation
dense, intramarginal vein close to margin, oil glands scattered intersectional,
large.
Inflorescences axillary unbranched, peduncles 1-1.5 cm long;
buds 7, pedicellate, ovoid, scar present, operculum conical or sometimes
slightly beaked, outer stamens erect, inner stamens inflexed, anthers
oblong, versatile, dorsifixed, dehiscing by longitudinal slits, style
long and straight, stigma blunt, locules 3 or 4, the placentae each
with 4 vertical rows of ovules; flowers white.
Fruit pedicellate, usually hemispherical, 1-1.4 cm wide, disc
broad and flat sloping inwards slightly at the inner edge, valves
3 or 4, at rim level.
Seed rarely formed and when formed not fertile; brown, 1-2
mm long, flattened-ovoid, dorsal surface more or less smooth, hilum
ventral. Fruit contain mostly chaff particles.
Cultivated seedlings not seen.
NOTES
Eucalyptus annuliformis (Latin, annuliformis,
ringlike, referring to the disc of the fruit).
A mallee endemic to Western Australia, occuring north of Perth where
known only from a few plants on Badgerabbie Hill south-east of Dandaragan
and 2 farms to the north. Bark is smooth and the crown dull green.
Eucalyptus annuliformis probably belongs in Eucalyptus
subgenus Symphyomyrtus section Bisectae sub-section
Destitutae because buds have two opercula, branchlets lack
oil glands in the pith and internal bud features are like other species
in the group. Cotyledons however have not been seen. Within this sub-section
E. annuliformis fits best in series Curviptera, one
of about 30 closely related species and subspecies which are further
characterized by having large buds in umbels of 1, 3 or 7,
staminal filaments erect or oblique (rarely inflexed) in bud, and
large fruit usually with an ascending disc and exserted valves.
E. annuliformis appears to be closely related to E. drummondii
and may be a hybrid species deriving from it although the other
parent species is not obvious. It differs by the larger, non-glaucous
buds with beaked opercula, and by the fruit with an inward-sloping
disc which is unusual for this group of species. It produces heavy
bud and fruit crops but repeated collections have resulted in a copious
yield of chaff, very few seed none of which has germinated.
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