home | glossary | about eucalypts | about EUCLID | browse species

Eucalyptus angustissima subsp. quaerenda



Eucalyptus angustissima subsp. quaerenda L.A.S.Johnson & K.D.Hill, Telopea 4: 598 (1992).

T: Western Australia: 100 metres S of south shore of Lake Chinocup, 13 Nov 1986, K.D.Hill 2460, L.A.S.Johnson & D.F.Blaxell; holo: NSW; iso CANB, MEL, PERTH.


Mallee to 4 m tall, often rounded, with foliage to ground. Forming a lignotuber.
Bark smooth throughout, mottled pale grey, pale brown, pinkish-grey and whitish, ribbons sometimes present on lower trunks.
Branchlets lacking oil glands in the pith.
Juvenile growth (coppice or field seedlings to 50 cm): stems rounded in cross-section; juvenile leaves sessile to shortly petiolate, alternate, 4.5-8 cm long, 0.3-0.6 cm wide, lower leaves dull, bluish green, upper leaves green and glossy.
Adult leaves erect, alternate, petioles 0.2-0.5 cm long
; blade linear, 5.5-9 cm long, 0.4-0.7 cm wide, base tapering to petiole, margin entire, apex finely pointed and sometimes uncinate, concolorous, dull and bluish green at first soon maturing glossy, green, side-veins greater than 45° to midrib or obscure, reticulation moderate to dense or obscure, oil glands intersectional, +/- round.
Inflorescences axillary, single, peduncles 0.1-0.6 cm long; buds 7, pedicellate, ovoid (egg-in-eggcup) with hypanthium widest below the join with operculum, scar present, operculum rounded to conical, stamens inflexed, anthers oblong to reniform, versatile, dorsifixed, dehiscing by short lateral slits, style long, straight, stigma more or less blunt, locules 3, the placentae each with 4 vertical rows of ovules; flowers creamy white.
Fruit pedicellate or +/- sessile, broadly and shallowly cupular to obconical or flattened-globose and often swollen below rim, 0.5-0.7(0.8) cm wide, disc usually level, sometimes obliquely descending, valves 3, at rim level.
Seed tan, 1.0-2.5 mm long, flattened-ovoid, dorsal surface +/- smooth, at times slightly furrowed, hilum ventral.


Cultivated seedling (measured at ca node 10): cotyledons
Y-shaped (bisected); stem rounded in cross-section, smooth to slightly warty; leaves usually sessile, the lower nodes sometimes crowded, opposite for ca 6 nodes then alternate, linear, thickened and slightly incurved, 4.5-9 cm long, 0.2-0.5 cm wide, green to grey-green, margin may be entire or irregular.


NOTES

Eucalyptus angustissima (Latin, the superlative of angustus, narrow, referring to the leaves).

A mallee endemic to Western Australia. The species occurs in southern coastal and subcoastal areas from Lake Chinocup and north-west of Ravensthorpe eastwards to Esperance and Israelite Bay. The bark is smooth and the crown of erect, dull to glossy, green leaves. The species is notable for the narrowest adult leaves of all eucalypts.

Eucalyptus angustissima belongs in Eucalyptus subgenus Symphyomyrtus section Bisectae sub-section Destitutae because buds have two opercula, cotyledons are Y-shaped and branchlets lack oil glands in the pith. Within this sub-section E. angustissima is closely related to only two other species, viz. E. foliosa and E. misella , together forming series Angustissimae, characterized by the erect leaves, egg-in-eggcup buds and stamens with more or less reniform anthers. The habitat of both subspecies of E. angustissima is similar to that of E. foliosa being white sands in the vicinity of salt lakes, whilst E. misella occurs away from salt lakes on sand with gravel high in the profile.

E. angustissima differs from E. misella and E. foliosa in having leaves always less than 0.8 cm wide, buds only in umbels of 7s (7, 9 and 11 in the other two species).

There are two subspecies of E. angustissima:

subsp. angustissima,

leaves less than 0.4 cm wide; found sporadically from north of Esperance to Israelite Bay.

subsp. quaerenda (from Latin, quaerendus, to be sought, alluding to early searches for these plants),

leaves 0.4-0.7 cm wide; found at Lake Chinocup and between Ravensthorpe and Lake King.