Paynes Find Mallee (Eucalyptus crucis subsp. Praecipua) Interim Recovery Plan 2004-2009

Western Australian Threatened Species and Communities Unit (WATSCU)
© The Western Australian, Department of Conservation and Land Management, 2004

4. Term of Plan

This Interim Recovery Plan will operate from June 2004 to May 2009 but will remain in force until withdrawn or replaced. If the taxon is still ranked Endangered after five years, the need for further recovery actions will be determined.

5. References

Brooker, M.I.H. and Hopper, S.D. (1982) New subspecies in Eucalyptus caesia and in E. crucis (Myrtaceae) of Western Australia. Nuytsia 4(1), 113-128.

Brooker, M.I.H. and Hopper, S.D. (1993) New series, subseries, species and subspecies of Eucalyptus (Myrtaceae) from Western Australia and from South Australia. Nuytsia 9(1), 1-68.

Brooker, M.I.H. and Kleinig, D.A. (1990) Field Guide to Eucalypts, Volume 2 South-western and Southern Australia. Inkata Press, Melbourne.

Brown, A., Thomson-Dans, C. and Marchant, N. (Eds). (1998) Western Australias Threatened Flora. Department of Conservation and Land Management, Western Australia.

Chippendale, G.M. (1988) Eucalyptus. Flora of Australia 19: 1-447. Australian Biological Resources Study, Canberra.

Department of Conservation and Land Management (2003) Western Australian Herbarium FloraBase 2 Information on the Western Australian Flora. Accessed 2003. http://www.calm.wa.gov.au/science/

Department of Conservation and Land Management (1995) Policy Statement No. 29 Translocation of Threatened Flora and Fauna. Perth, Western Australia.

Department of Conservation and Land Management (1994) Policy Statement No. 50 Setting Priorities for the Conservation of Western Australias Threatened Flora and Fauna. Perth, Western Australia.

Department of Conservation and Land Management (1992) Policy Statement No. 44 Wildlife Management Programs. Perth, Western Australia.

Department of Conservation and Land Management (1990 onwards) Threatened Flora Database (DEFL). Perth , Western Australia. Accessed 2003.

IUCN (2000) IUCN Red List Categories prepared by the IUCN Species Survival Commission, as approved by the 51st Meeting of the IUCN Council. Gland, Switzerland.

Nicolle, D. (2001) Notes on Eucalyptus series Orbifoliae (Myrtaceae) including a new species from central Australia. Nuytsia 13(3), 487-493.

Sampson, J.F. (1988) The population genetic structure of Eucalyptus rhodantha Blakely & Steedman and its allies Eucalyptus crucis Maiden and Eucalyptus lane-poolei Maiden. PhD Thesis, University of Western Australia.

Sampson, J.F., Hopper, S.D. and James, S.H. (1988) Genetic Diversity and the Conservation of Eucalyptus crucis Maiden. Australian Journal of Botany 36, 447-460.

Yates, C.J., Hopper, S.D., Brown, A. and van Leeuwen, S. (2003) Impact of two wildfires on endemic granite outcrop vegetation in Western Australia. Journal of Vegetation Science 14, 185-194.

6. Taxonomic Description

Brooker, M.I.H. and Hopper, S.D. (1993) New series, subseries, species and subspecies of Eucalyptus (Myrtaceae) from Western Australia and from South Australia. Nuytsia 9(1), 1-68.

Eucalyptus crucis subsp. praecipua

It differs from subspecies lanceolata in the larger adult leaves, buds and fruits.

Distribution: Only known from the type locality.

Conservation status: Vulnerable, declared as Rare Flora.

Flowering period: Not known.

Etymology: From the Latin praecipua special, in allusion to its distinct morphology and isozyme constituents.

Notes: Apart from the morphological distinction of the new subspecies, a study by Sampson et al. (1988) on isozymes showed that the maximum genetic distance between the morphologically similar subsp. lanceolata and subsp. praecipua was much larger than the distance of subsp. lanceolata from the morphologically dissimilar subsp. crucis.

Brooker, M.I.H. and Hopper, S.D. (1982) New subspecies in Eucalyptus caesia and in E. crucis (Myrtaceae) of Western Australia. Nuytsia 4(1), 113-128.

Eucalyptus crucis subsp. lanceolata

A large erect mallee to 15 m tall with imperfectly decorticated, crisped Minni Ritchi bark on stems to about 30 cm diameter. Young branchlets smooth, white, glaucous. Seedling and juvenile leaves remaining opposite for many nodes, sessile, orbicular or broader than long, conspicuously mucronate, to 5 x 3.5 cm, with minute black oil dots, greyish green. Intermediate leaves opposite or sub-opposite, sub-sessile or shortly and distinctly petiolate, ovate, to 6 x 2 cm, grey-green. Adult leaves alternate, on slender petioles 5-15 mm long, lanceolate to narrow-lanceolate, to 10 x 2 cm, tapering to a fine, sometimes curved point, with many minute, black oil dots. Inflorescences axillary, 7-flowered; peduncles and pedicels slender; buds glaucous, to 6 x 4 mm, hypanthium hemispherical, operculum obtusely or acutely conical, outer operculum lost early in bud development. Fruit on long, slender pedicels, hemispherical, glaucous, to 16 x 10 mm; disc broad, flat or slightly ascending; valves 4, stout, strongly exserted.

Distribution. (Figure 5) Restricted to a number of granite rocks in the central wheatbelt of Western Australia.

Ecology. Eucalyptus crucis subsp. lanceolata occurs in shallow granitic sands and loams associated with large outcrops of granite rocks. It displays a clumped distribution at any particular location. It is sometimes associated with Eucalyptus caesia subsp. magna (e.g. at Chiddarcooping Hill, Ballyacatting Hill), and with E. orbifolia at Jouerdine Hill. It has not been found in sympatry with E. crucis subsp. crucis.

Discussion. Eucalyptus crucis subsp. lanceolata and E. crucis subsp. crucis differ in having adult leaves and juvenile leaves respectively in their mature canopies. They show no obvious differences in the morphology of their fruits, buds or flowers. Elsewhere in Eucalyptus, related adult-leaved and juvenile-leaved taxa have been recognised as distinct species (e.g. E. gamophylla F. Muell. E. odontocarpa F. Muell., E. risdonii Hook. f. E. tenuiramis Miq., E. fruticosa M.I.H. Brooker E. foecunda Schau.). However, in E. crucis, the typical subspecies shows a range in leaf form from populations stabilised for orbicular, apetiolate, fully juvenile leaves (e.g. at Sandford Rock) to populations with ovate, shortly petiolate leaves that are intermediate between the juvenile and adult conditions (e.g. at Moorine Rocks or Warren Double Cunyan) (Figure 5 and Table 1). These intermediate populations indicate that the genetic fixation of a fully juvenile-leaved form in E. crucis subsp. crucis has not yet occurred. Hence we feel it appropriate to recognise the two forms in E. crucis as subspecies rather than separate species.

Previously, E. crucis subsp. lanceolata has been confused with a number of species, including E. leptopoda, E. drummondii and E. orbifolia (e.g. Gardner, 1954). However it is clearly distinct from the first two of these three taxa in having crisped Minni Ritchi bark and in its restriction to granite rocks. It differs from E. orbifolia in having acute, non-emarginate, lanceolate to narrow-lanceolate leaves.