Eucalyptus alligatrix L.A.S.Johnson & K.D.Hill, Austral.
Syst. Bot. 8: 509 (1995) subsp. alligatrix.
T: Victoria: Big River, near junction with Taponga River, SW of Jamieson,
24 Apr. 1973, L.A.S.Johnson 7675; holo:NSW.
Tree to 15 m tall, rarely multi-stemmed from base. Forming
Bark rough to small branches or rarely the branches <8cm
diam. smooth, rough bark thick, fibrous, coarsely furrowed down trunk,
dark grey; branchlets glaucous or non-glaucous.
Juvenile growth (coppice or field seedlings to 50 cm):stem
rounded or square in cross-section, glaucous or not glaucous, warty
or smooth; juvenile leaves always opposite, sessile, orbicular or
broadly ovate, 2-4.5 cm long, 2.5-5.2 cm wide, margin entire or crenulate,
blue-green, grey-green or glaucous.
Crown composed of opposite, petiolate intermediate leaves and
alternate adult leaves.
Adult leaves petiole 0.6-2.4 cm long; blade lanceolate to falcate,
5.4-20 cm long, 1-4.7 cm wide, base tapering to petiole, margin entire,
concolorous, glossy or dull, green, blue-green or grey-green, side-veins
greater than 45° to midrib,
moderately to densely reticulate, intramarginal vein parallel to and
just within margin or well removed from it, oil glands numerous, mostly
Inflorescences axillary single, peduncles 0.3-0.7 cm long;
buds 3, pedicellate or sessile, ovoid to diamond-shaped, green or
glaucous, scar present, operculum conical, stamens inflexed, anthers
cuboid or cuneate, versatile, dorsifixed, dehiscing by longitudinal
slits (non-confluent), style long, locules 3 or 4, the placentae each
with 4 vertical ovule rows; flowers white.
Fruit sessile or shortly pedicellate, cup-shaped, obconical
or campanulate, 0.4-0.8 cm wide, sometimes glaucous, disc raised or
level, valves 3 or 4, strongly exserted or near rim level.
Seed dark brown, 1-2.2 mm long, ovoid or flattened-ovoid, D-shaped
or pointed at one end, usually lacunose, dorsal surface smooth or
shallowly pitted, hilum ventral.
Cultivated seedlings (measured at ca node 10): cotyledons bilobed
to oblong; stems rounded or squared in cross-section, glaucous; leaves
sessile and opposite for many nodes, orbicular to cordate, 2.5-4.5
cm long, 2.2-6.5 cm wide, base amplexicaul to rounded, apex emarginate,
rounded or pointed, glaucous to grey-green.
Eucalyptus alligatrix (
Latin alligatrix, she who binds together, refers to the relationship
of the species to E. cinerea and E. cephalocarpa ).
A small to medium-sized tree of undulating to montane south-eastern
Australia inland from the Great Dividing Range.
E. alligatrix has extensive, thick rough fibrous bark, glaucous
juvenile leaves and a crown of adult and intermediate leaves.
It has three subspecies differing in geography and proportion
of adult and sub-adult leaves in the crown:
From the Eildon - Jamieson - Big River area of Victoria with
buds in 3s and crown a mixture of alternate narrow adult and opposite
broader intermediate leaves.
subsp. limaensis (after the farming district, Lima, in north-east
Victoria, where the subspecies occurrs).
Occurs further north than subsp. alligatrix, only near Swanpool
in Victoria. A taller tree with a completely adult crown of consistently
alternate narrow leaves, buds in 3s and the smallest fruit of the
subsp. miscella (Latin miscella, mixed, refers to the
3 and 7-flowered inflorescences on the same tree).
Has a very restricted distribution near Rylstone, New South Wales,
and is a smaller spreading woodland tree with a completely adult crown
but with broader leaves than subsp. limaensis. Buds clusters
are a mixture of 3s and 7s on the same tree.
alligatrix 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.
alligatrix belongs in series Argyrophyllae having longitudinally
furrowed fibrous rough bark throughout, orbicular or ovate juvenile
leaves opposite for many nodes and small diamond-shaped buds in 3s
or mixed 3s and 7s. E. alligatrix has a greener, more adult-leaved
crown than E. cinerea and E. conspicua whilst E.
cephalocarpa and E. nova-anglica have buds in 7s. These
5 species form series Argyrophyllae.