Eucalyptus saxicola J.T.Hunter - removal of endangered species

NSW Scientific Committee - final determination

The Scientific Committee, established by the Threatened Species Conservation Act, has made a Final Determination to remove Eucalyptus saxicola J.T.Hunter from the Schedules of the Act by omitting reference to this species from Part 1 of Schedule 1 (Endangered species). The omission of this species from the Schedules is provided for by Part 2 of the Act.

 

The Scientific Committee has found that:

 

1. Eucalyptus saxicola J.T.Hunter (family Myrtaceae) was described by Hunter (2001) as: “Small tree 6–15 m tall with a box bark persistent to larger branches, then shed in long strips. Stems terete, glandular to erect-warty on juvenile and sucker stems. Juvenile leaves orbicular becoming broadly ovate, glaucous, 1.5–4 cm long, 1.5–4 cm wide, margins crenulate and slightly recurved, opposite becoming subopposite at about the fourth internode, apex rounded and mucronate to shortly acute, base deeply cordate, sessile. Intermediate leaves broadly ovate elliptic to broad lanceolate, 4–13 cm long, 3–6.5 cm wide, falcate, alternate, ± glaucous, apex acuminate and ± hooked, base rounded to attenuate and oblique, with petioles 1–4 cm long. Adult leaves alternate, linear to narrow lanceolate, 12.5–23 cm long, 1.1–2.3 cm wide, with conspicuous oil dots, conspicuously glossy and dark green, never glaucous, falcate, margins entire, apex acuminate and often hooked, base attenuate and oblique, petiole terete to flattened, channeled, 2–4 cm long, venation 25–35 degrees to midrib, intramarginal vein 0.8–1.4 mm from the margin, midrib flat to channelled above. Inflorescence of 7-flowered axillary umbellasters. Peduncle flattened to ovoid in section, 1–4 mm long in bud, 3–9 mm long in fruit; pedicel 1–2.4 mm long in bud, absent or to 3 mm long in fruit. Buds turbinoid to clavoid, 3.5–4.5 mm long, 2.3–2.7 mm wide, not glaucous; calyptra hemispherical to shortly beaked hemispherical, 1.5–2.3 mm long, 2.3–2.7 mm wide; hypanthium obloid, 1.5–2.4 mm long, 2.2–2.6 mm wide. Ovules in 4 rows; style terete, 2–3 mm long. Stamens irregularly inflexed; filaments 2.5–3.5 mm long; anthers dorsifixed, parallel, 0.5–0.6 mm long, white, dehiscence longitudinal; connective oil gland orbicular and abaxial. Fruits hemispherical, 3.5–5.2 [mm] long, 4.3–6 mm wide, slightly ribbed, often splitting on one side, disc level to convex, 0.4–0.8 mm wide, scar distinct; valves 3–4, level to exserted. Seeds smooth to shallowly reticulate, red-brown to yellow-brown, cuboid, strongly angular, rounded terminal or central hilum on flat polygonal surface, 0.9–1 mm long, 0.5–0.8 mm wide. Cotyledons bilobed.”

 

2. Hill (2002), in the Flora of New South Wales, alludes to this taxon as a possible segregate from E. bridgesiana R.T.Baker. However, the National Herbarium of New South Wales currently considers E. saxicola to be a synonym of E. bridgesiana (NSW Flora online accessed 4 Nov. 2011).

 

3. Brooker et al. (2006) assess this taxon as follows: “In 2001 Eucalyptus saxicola was described from small populations near the summit of Mount Canobolas, near Bathurst, New South Wales, differing from E. bridgesiana primarily in having smaller juvenile leaves (< 4 cm wide and long), more hemispherical operculum, and in being a smaller plant. From our field and herbarium experience E. bridgesiana frequently has juvenile leaves < 4 cm wide and long, and opercula varying from conical to hemispherical, often with a beak or apiculum, throughout its wide geographic range from Stanthorpe and Ballandean in Queensland south to Suggan Buggan, Bairnsdale and Glenrowan in Victoria. Stature, flatness of the peduncles and length of the pedicels also are variable throughout the species range. The Mount Canobolas populations lack the exserted valves of the fruit typical of E. bridgesiana, a feature worthy of note but insufficient to maintain a species difference. We therefore synonymize E. saxicola with E. bridgesiana.”

 

4. Dean Nicolle (pers. comm., 19 August 2011) has seen and collected Hunter’s E. saxicola from Mt Canobolas and has grown seed collected on Mt Canobolas at the Currency Creek Arboretum in South Australia. He considers there is no difference in the juvenile leaves of E. saxicola and E. bridgesiana and suggests the plant stature of E. saxicola appears to be environmentally determined. He considers it is synonymous with E. bridgesiana.

 

5. Based on this information Eucalyptus saxicola J.T.Hunter is not currently recognised as a distinct taxon.

 

6. In view of the above the Scientific Committee is of the opinion that Eucalyptus saxicola J.T.Hunter is no longer eligible to be listed as an Endangered species in Part 1 of Schedule 1 of the Act.

 

Associate Professor Michelle Leishman

Chairperson

Scientific Committee

 

Proposed Gazettal date: 17/08/12

Exhibition period: 17/08/12 – 12/10/12

 

References:

 

Brooker MIH, Slee AV, Connors JR, Duffy SM (2006) EUCLID: eucalypts of Australia, ed. 3. CSIRO Publishing.

 

Hill KD (2002) Eucalyptus. In ‘Flora of New South Wales’ (Ed. GJ Harden) Vol. 2, edn. 2, pp. 96–164.

 

Hunter JT (2001) Eucalyptus saxicola (Myrtaceae), a new species from the Central Tablelands of New South Wales (section Maidenaria series Bridgesianae). Telopea 9: 403–407.

 

NSW Flora online (accessed 4 November 2011) http://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Eucalyptus~bridgesiana

Page last updated: 17 August 2012