Casuarina, also known as she-oak, Australian pine[3][4][5] and native pine,[6] is a genus of flowering plants in the family Casuarinaceae, and is native to Australia, the Indian subcontinent, Southeast Asia, islands of the western Pacific Ocean, and eastern Africa.
Plants in the genus Casuarina are monoecious or dioecious trees with green, pendulous, photosynthetic branchlets, the leaves reduced to small scales arranged in whorls around the branchlets, the male and female flowers arranged in separate spikes, the fruit a cone containing grey or yellowish-brown winged seeds.
Descriptionedit
Plants in the genus Casuarina are dioecious trees (apart from C. equisetifolia that is monoecious), with fissured or scaly greyish-brown to black bark. They have soft, pendulous, green, photosynthetic branchlets, the leaves reduced to scale-like leaves arranged in whorls of 5 to 20 around the branchlets. The branchlets are segmented at each whorl with deep furrows that conceal the stomates. Male flowers are arranged along branchlets in spikes with persistent bracteoles, female flowers in spikes on short side-branches (effectively "peduncles") that differ in appearance from vegetative branchlets. After fertilisation, the female spikes develop into "cones" with thin, woody bracteoles that extend well beyond the cone body. The cones enclose grey or yellowish-brown winged seed known as samaras.[7][8][9][10][11][12]
Ecologyedit
Casuarina are attacked by a range of herbivorous insects.
Hymenoptera: The wasps Bootanelleus orientalis and another Bootanelleus species (Torymidae) feed on seeds.[13]Selitrichodes casuarinae and S. utilis (Eulophidae) induce galls.[14]
Curculionidae: A weevil in genus Haplonyx feeds on cones. The genera Misophrice and Apion have also been recorded on Casuarina, but the nature of their associations is unknown.[13]
Hemiptera: Casuarinicola jumping plant lice (Triozidae) feed on sap of Casuarina.[15] Another hemipteran associated with this genus is the felt scale Choneochiton casuarinae (Eriococcidae).[16]
Diptera: The gall midge Ophelmodiplosis clavata (Cecidomyiidae) induces galls on branchlet tips.[17]
^Wilson, Karen L.; Johnson, Lawrence A.S. George, Alex S. (ed.). "Casuarina". Australian Biological Resources Study, Department of Climate Change, the Environment and Water: Canberra. Retrieved 22 April 2023.
^ abc"Ecology and Management of Sheoak (Casuarina spp.), an Invader of Coastal Florida, U.S.A." (PDF). Journal of Coastal Research. 27 (3): 485. 2011-05-01. doi:10.2112/JCOASTRES-D-09-00110.1. ISSN 0749-0208. S2CID 55348868.
^Fisher, Nicole; Moore, Aubrey; Brown, Bradley; Purcell, Matthew; Taylor, Gary S.; Salle, John La (2014-04-23). "Two new species of Selitrichodes (Hymenoptera: Eulophidae: Tetrastichinae) inducing galls on Casuarina (Casuarinaceae)". Zootaxa. 3790 (4): 534–542. doi:10.11646/zootaxa.3790.4.2. ISSN 1175-5334. PMID 24869885.
^Taylor, Gary S.; Austin, Andy D.; Jennings, John T.; Purcell, Matthew F.; Wheeler, Gregory S. (2010-09-02). "Casuarinicola, a new genus of jumping plant lice (Hemiptera: Triozidae) from Casuarina (Casuarinaceae)". Zootaxa. 2601 (1): 1. doi:10.11646/zootaxa.2601.1.1. ISSN 1175-5334.
^Hodgson, Chris; Mille, Christian; CazèRes, Sylvie (2014-03-05). "A new genus and species of felt scale (Hemiptera: Coccoidea: Eriococcidae) from New Caledonia". Zootaxa. 3774 (2): 152–164. doi:10.11646/zootaxa.3774.2.3. ISSN 1175-5334. PMID 24871412.
^Kolesik, Peter; Brown, Bradley T; Purcell, Matthew F; Taylor, Gary S (2012). "A new genus and species of gall midge (Diptera: Cecidomyiidae) from Casuarina trees in Australia: New gall midge from Casuarina". Australian Journal of Entomology. 51 (4): 223–228. doi:10.1111/j.1440-6055.2012.00860.x.
^Linnaeus, Carl (1759). Amoenitates academicae, seu, Dissertationes variae physicae, medicae, botanicae. p. 143. Retrieved 21 April 2023.
^Quattrocchi, Umberto (2000). CRC World Dictionary of Plant Names. Vol. I A-C. CRC Press. p. 456. ISBN 978-0-8493-2675-2.
^Govaerts R. "Casuarina L.". Plants of the World Online. Board of Trustees of the Royal Botanic Gardens, Kew. Retrieved 20 April 2023.
^Johnson, Lawrence A. (1982). "Note on Casuarinaceae II". Journal of the Adelaide Botanic Gardens. 6 (1): 73–86. Retrieved 21 April 2023.
^BEST Commission (March 2003). "The National Invasive Species Strategy for The Bahamas". Nassau, The Bahamas: BEST. Archived from the original on 2011-07-06.
^"Casuarina (Casuarina equisetifolia)". Department of Conservation. Government of Bermuda. Archived from the original on 2010-03-05. Retrieved 2010-10-01.
External linksedit
Wikimedia Commons has media related to Casuarina.
"Casuarina L.: Queensland Oak". Atlas of Living Australia.