Casuarinaceae

'Cones' of Casuarina equisetifolia, photographed by Atamari.

Belongs within: Faganae.

The Casuarinaceae, sheoaks, are a family of just under 100 species of small trees that bear a superficial resemblance to conifers, with scale-like leaves and cone-like inflorescences. Species of Casuarinaceae are found in south-east Asia and Australasia; the genus Allocasuarina is restricted to Australia but Casuarina is more widespread. Species of Allocasuarina bear 'cones' with thinly woody, prominent bracteoles extending well beyond the body of the cone whereas cones of Casuarina species have thickly woody, convex bracteoles mostly extending only slightly beyond the cone body (Harden 1990).

Characters (from the Angiosperm Phylogeny Website): Roots with N-fixing Frankia, rootlets clustered, of limited growth ; flavonols and biflavonoids present, flavones and myricetin absent; nodes 1:1; stomata usually tetracytic, transversely oriented; leaves 4-16-whorled, scale-like, margins entire, stipules absent; plant monoecious or dioecious, inflorescence capitate-spicate, one flower/bract, bracts and bracteoles more or less well-developed; staminate flowers with perianth ["inner bracteoles"] 2, median, androecium 1, filaments incurved in bud, anthers more or less longer than connective; pollen granular layer absent; pistillode absent; carpellate flowers with bracteoles large; perianth absent; gynoecium naked, only abaxial fertile; ovules bitegmic, outer integument 3-4 cells across, inner integument 2-3 cells across, micropyle endostomal, nucellar tracheids present, vascular bundle branched in chalaza; archesporium multicellular, embryo sac with micropylar and chalazal caecum/haustoria; fruit a samara, freed as the much accrescent bracteoles separate; seed coat adnate to pericarp; endosperm anbsent; n = 8-14.

Casuarinaceae [Casuarinales, Casuarinanae]
    |--Casuaroxylon anglica Goeppert & Stache 1855 CBH93
    |--Gymnostoma CBH93
    |--Haloragacidites harrisii Mildenhall 1980 [=Triorites harrisii] CBH93
    |--Casuarina W95
    |    |--C. cristata [incl. C. cambagei, C. lepidophloia] H90
    |    |--C. cunninghamiana M04
    |    |--C. decaisneana B05
    |    |--C. equisetifolia B88
    |    |    |--C. e. ssp. equisetifolia H90
    |    |    `--C. e. ssp. incana H90
    |    |--C. fraserana W95
    |    |--C. glauca C74
    |    |--C. humilis SM06
    |    |--C. litorea A80
    |    |--C. littoralis S00 [=Allocasuarina littoralis H90; incl. C. suberosa H90]
    |    |--C. muelleriana G76
    |    |--C. nobilis P88
    |    |--C. obesa OS04
    |    |--C. papuana C78
    |    |--C. pauper M04
    |    `--C. sumatrana K03
    `--Allocasuarina SM06
         |--A. acutivalvis G04b
         |--A. brachystachya H90
         |--A. campestris OS04
         |--A. corniculata G04a
         |--A. decussata M06
         |--A. defungens H90
         |--A. diminuta H90
         |    |--A. d. ssp. diminuta H90
         |    |--A. d. ssp. annectens H90
         |    `--A. d. ssp. mimica H90
         |--A. distyla [=Casuarina distyla]
         |--A. eriochlamys G04a
         |--A. fraseriana SM06
         |--A. glareicola H90
         |--A. gymnanthera H90
         |--A. helmsii G04a
         |--A. huegeliana SB04
         |--A. humilis OS04
         |--A. inophloia [=Casuarina inophloia] H90
         |--A. luehmannii [=Casuarina luehmannii] H90
         |--A. microstachya OS04
         |--A. nana [=Casuarina nana] H90
         |--A. ophiolitica H90
         |--A. paludosa [=Casuarina paludosa; incl. C. distyla var. prostrata] H90
         |--A. portuensis H90
         |--A. rigida [=Casuarina rigida] H90
         |--A. rupicola H90
         |--A. simulans H90
         |--A. thuyoides G04b
         |--A. torulosa [=Casuarina torulosa] H90
         `--A. verticillata [incl. Casuarina quadrivalvis, C. stricta] H90

*Type species of generic name indicated

REFERENCES

[A80] Aoki, J. 1980. A revision of the oribatid mites of Japan. I. The families Phthiracaridae and Oribotritiidae. Bulletin of the Institute of Environmental Science and Technology, Yokohama National University 6 (2): 1–89.

[B05] Beard, J. S. 2005. Drainage evolution in the Lake Disappointment Catchment, Western Australia—a discussion. Journal of the Royal Society of Western Australia 88 (2): 57–64.

[B88] Bouček, Z. 1988. Australasian Chalcidoidea (Hymenoptera): A biosystematic revision of genera of fourteen families, with a reclassification of species. CAB International: Wallingford (UK).

[C78] Clunie, N. M. U. 1978. The vegetation. In: Womersley, J. S. (ed.) Handbooks of the Flora of Papua New Guinea vol. 1 pp. 1–11. Melbourne University Press: Carlton South (Australia).

[CBH93] Collinson, M. E., M. C. Boulter & P. L. Holmes. 1993. Magnoliophyta (‘Angiospermae’). In: Benton, M. J. (ed.) The Fossil Record 2 pp. 809–841. Chapman & Hall: London.

[C74] Crowder, J. P. 1974. Exotic Plant Pests of South Florida. Bureau of Sport Fisheries and Wildlife (USA).

[G04a] Gibson, N. 2004a. Flora and vegetation of the Eastern Goldfields Ranges: part 6. Mt Manning Range. Journal of the Royal Society of Western Australia 87 (2): 35–47.

[G04b] Gibson, N. 2004b. Flora and vegetation of the Eastern Goldfields Ranges: part 7. Middle and South Ironcap, Digger Rock and Hatter Hill. Journal of the Royal Society of Western Australia 87 (2): 49–62.

[G76] Gross, G. F. 1976. Plant-feeding and Other Bugs (Hemiptera) of South Australia. Heteroptera—Part II. Handbook of the Flora and Fauna of South Australia.

[H90] Harden, G. J. (ed.) 1990. Flora of New South Wales vol. 1. New South Wales University Press.

[K03] Kulip, J. 2003. An ethnobotanical survey of medicinal and other useful plants of Muruts in Sabah, Malaysia. Telopea 10 (1): 81–98.

[M06] McCaw, W. L. 2006. Asplenium aethiopicum recolonises karri forest following timber harvesting and burning. Journal of the Royal Society of Western Australia 89 (3): 119–122.

[M04] Mound, L. A. 2004. Australian Thysanoptera—biological diversity and a diversity of studies. Australian Journal of Entomology 43 (3): 248–257.

[OS04] Obbens, F. J., & L. W. Sage. 2004. Vegetation and flora of a diverse upland remnant of the Western Australian wheatbelt (Nature Reserve A21064). Journal of the Royal Society of Western Australia 87 (1): 19–28.

[P88] Polunin, I. 1988. Plants and Flowers of Malaysia. Times Editions: Singapore.

[SB04] Sage, L. W., P. A. Blankendaal, A. Moylett & K. Agar. 2004. The occurrence and impact of Phytophthora cinnamomi in the central-western Avon Wheatbelt bioregion of Western Australia. Journal of the Royal Society of Western Australia 87 (1): 15–18.

[SM06] Semeniuk, C. A., L. A. Milne, P. Ladd & V. Semeniuk. 2006. Pollen in the surface sediments of wetlands in the Becher Point area, southwestern Australia: a baseline for use in interpreting Holocene sequences. Journal of the Royal Society of Western Australia 89 (1): 27–43.

[S00] Siddiqi, M. R. 2000. Tylenchida: Parasites of plants and insects 2^nd ed. CABI Publishing: Wallingford (UK).

[W95] Wang, Q. 1995. A taxonomic revision of the Australian genus Phoracantha Newman (Coleoptera: Cerambycidae). Invertebrate Taxonomy 9: 865–958.

Last updated: 6 July 2020.