The World Flora Online

SELECTED REFERENCES

Johnson, L. A. S. and K. L. Wilson. 1989. Casuarinaceae: A synopsis. In: P. R. Crane and S. Blackmore, eds. 1989. Evolution, Systematics and Fossil History of the Hamamelidae. 2 vols. Oxford. Vol. 2, pp. 167-188. [Syst. Assoc. Special Vol. 40A,B.] Johnson, L. A. S. and K. L. Wilson. 1993. Casuarinaceae. In: K. Kubitzki et al., eds. 1990+. The Families and Genera of Vascular Plants. 2 + vols. Berlin etc. Vol. 2, pp. 237-242. Rogers, G. K. 1982b. The Casuarinaceae in the southeastern United States. J. Arnold Arbor. 63: 357-373. Wilson, K. L. and L. A. S. Johnson. 1989. Casuarinaceae. In: R. Robertson et al., eds. 1981+. Flora of Australia. 14+ vols. Canberra. Vol. 3, pp. 100-174. Woodall, S. L. and T. F. Geary. 1985. Identity of Florida casuarinas. Res. Notes S E, U.S. Forest Serv. 332: 1-10.

Trees [or shrubs], evergreen. Photosynthetic branchlets slender, wiry, with several very short, basal segments and 1-numerous elongate segments; segments terete [quadrangular], with as many longitudinal ridges as leaves; ridges separated by furrows containing stomates. Leaves reduced to small teeth in whorls of [4-]6-17 at apex of each segment of photosynthetic branchlets. Inflorescences of alternating whorls of flowers, each flower subtended by toothlike bract and 2 bracteoles, bracteoles usually persistent, lateral, scalelike; staminate inflorescences catkinlike spikes, short to elongate; pistillate inflorescences heads, globular to ovoid. Flowers unisexual, staminate and pistillate on same or different plants. Staminate flowers : sepals deciduous at anthesis, 1-2, hooded, scalelike; stamen 1; anthers basifixed, 2-locular. Pistillate flowers : perianth absent; pistil 1, compound, 2-carpellate, 1 fertile, the other usually reduced or absent; ovules 2, an additional 2 abortive ovules in reduced carpel; styles 2-branched, reddish. Infructescences ± woody, cylindric, conelike; floral bracteoles 2, enlarged as lateral valves. Fruits compressed, winged nuts (samaras). Seeds 1 in each samara.

Arbres'ou arbustes, à port d' Equisetum , monoïques ou dioïques, à rameaux de dernier ordre portant à leur extrémité des ramules grêles et caducs, rigides, dressés ou pendants, articulés aux nœuds, cylindriques et verticillés, ou tétragones et épars.'Feuilles'réduites à de petites écailles verticillées par 4 ou plus à chaque nœud, parfois réunies en une gaine et à nervure médiane décurrente et formant les angles du rameau.'Inflorescences'♂ en épis simples ou composés, généralement terminales sur des rameaux caducs.'Fleurs'munies de 1-4 bractéoles cohérentes au-dessus de l'étamine unique infléchie dans le bouton et à filet accrescent; anthère 2-loculaire à déhiscence longitudinale.'Inflorescences'♀ en capitules sphériques à ovoïdes, terminales ou latérales sur des rameaux persistants.'Fleurs'munies de 2 bractéoles; ovaire 1-loculaire, à 2 ovules collatéraux semi-anatropes; style 1, court, à 2 branches stigmatiques longues et filiformes.'Capitules'fructifères strobiliformes par accrescence des bractées et des bractéoles lignifiées-indurées.'Akènes comprimés latéralement, ailés au sommet et situés entre les 2 bractéoles.\n\t\t\tUn seul genre groupant une cinquantaine d'espèces, nombreuses en Australie et en Nouvelle-Calédonie, moins nombreuses en Malaisie, dans les îles du Pacifique, les îles Mascareignes, à Madagascar, Zanzibar et en Afrique tropicale orientale.

Male flower: a single stamen enclosed in bud by 1 or 2 (anterior and posterior) concave or cucullate, membranous perianth segments which fall as the stamen develops; mature anther exserted Female flower: perianth 0; ovary 1-locular with a short terminal style; stigmas 2, long slender, well-exserted at maturity Male inflorescence spicate (tab. 36, fig. 2), solitary and terminal on deciduous branchlets (rarely also axillary on woody branches), cylindrical but tapering to a sterile basal region; flowers sessile and solitary in the axil of each bract of a whorl, a pair of lateral scarious bracteoles enclosing each flower Female inflorescence globose or ovoid (tab. 36, fig. 2), shortly stalked or subsessile, axillary toward the ends of woody branches; flowers sessile in the axil of each bract of a whorl; bracteoles as in male flowers Infructescence cone-like, globular, ovoid or cylindrical; ± woody due to the enlargement and thickening of accrescent bracts and bracteoles of individual flowers, the latter much the larger (often with a dorsal protuberance) and forming pairs of valves enclosing the true fruit and opening when ripe Fruit a dark brown to black and shiny or pale grey-fawn and rather dull samara, laterally compressed, bearing a large ± translucent wing with a single longitudinal nerve excurrent at the apex Trees (shrubs), dioecious less often monoecious Branches of 2 kinds: normal persistent woody branches and deciduous green branchlets, the latter thin, flexible and little branched Leaves on both kinds of branches reduced to whorls of small triangular scale leaves united at the base (tab. 36, fig. 3), becoming free on the persistent branches; midribs decurrent to the node below giving a ribbed or grooved appearance to the internode; leaf whorls, and therefore also the ribs, alternating at consecutive nodes Flowers grouped into unisexual inflorescences with closely spaced, alternating whorls of bracts similar to the scale leaves Female flower: perianth 0; ovary 1-locular with a short terminal style; stigmas 2, long slender, well-exserted at maturity Male inflorescence spicate (tab. 36, fig. 2), solitary and terminal on deciduous branchlets (rarely also axillary on woody branches), cylindrical but tapering to a sterile basal region; flowers sessile and solitary in the axil of each bract of a whorl, a pair of lateral scarious bracteoles enclosing each flower Female inflorescence globose or ovoid (tab. 36, fig. 2), shortly stalked or subsessile, axillary toward the ends of woody branches; flowers sessile in the axil of each bract of a whorl; bracteoles as in male flowers Infructescence cone-like, globular, ovoid or cylindrical; ± woody due to the enlargement and thickening of accrescent bracts and bracteoles of individual flowers, the latter much the larger (often with a dorsal protuberance) and forming pairs of valves enclosing the true fruit and opening when ripe Fruit a dark brown to black and shiny or pale grey-fawn and rather dull samara, laterally compressed, bearing a large ± translucent wing with a single longitudinal nerve excurrent at the apex Trees (shrubs), dioecious less often monoecious Branches of 2 kinds: normal persistent woody branches and deciduous green branchlets, the latter thin, flexible and little branched Leaves on both kinds of branches reduced to whorls of small triangular scale leaves united at the base (tab. 36, fig. 3), becoming free on the persistent branches; midribs decurrent to the node below giving a ribbed or grooved appearance to the internode; leaf whorls, and therefore also the ribs, alternating at consecutive nodes Flowers grouped into unisexual inflorescences with closely spaced, alternating whorls of bracts similar to the scale leaves

Trees or shrubs evergreen, monoecious or dioecious. Ultimate branchlets jointed, with several short, basal articles and 1-numerous elongated articles, slender, ridged, often pubescent at least when young. Leaves small, toothlike, in whorls of 4 to ca. 20 (equal to number of ridges on branchlets); stipules absent. Inflorescences spikelike or headlike, with alternating whorls of toothlike bracts; within each bract a single flower, with 2 lateral scalelike bracteoles, persistent (rarely deciduous in male Allocasuarina); parts sometimes pubescent when young, mostly glabrous at maturity. Flowers unisexual, without pedicels. Male inflorescences spikes, terminal or lateral, terete, slender. Female inflorescences headlike, globose or ellipsoid, usually terminal on short, lateral branches. Male flowers: tepals 1 or 2, scalelike, deciduous, hooded; stamen 1; anthers 2-loculed, longitudinally dehiscent, basifixed. Female flowers: perianth none; carpels 2, fused; only anterior carpel fertile, posterior carpel usually ± reduced or obsolete; ovules 2 (rarely 4), parietal, paired at base of carpel, chalazogamous; style short; stigmas 2, red, linear. Infructescences ± woody, conelike, with dense whorls of fruit, with 2 bracteoles of each flower enlarged as valves, persistent. Samaras flat, (usually) winged at apex, initially enclosed by 2 bracteoles, which separate at maturity to release samara. Seed 1; cotyledons large; endosperm absent; embryo straight, often more than 1.

Female flower without perianth; ovary single; style short, with 2 long filiform well-exserted stigmas Infructescence cone-like, globular, ovoid or cylindrical, ± woody, formed by enlargement and thickening of accrescent bracts and bracteoles of the individual flowers, the latter usually the more elongated and forming pairs of valves enclosing the true fruit and opening when ripe Fruit a samara, very much laterally compressed, apex produced into large ± translucent wing with 1 longitudinal nerve Trees or shrubs, monoecious or more often dioecious Leaves on both kinds of branches reduced to whorls of small triangular scales united at base; midribs decurrent to lower node giving a ribbed or grooved appearance to internode; on persistent stems leaves becoming separate as stem thickens; leaf-whorls, and therefore also ribs, alternating at consecutive nodes Branches of two kinds: normal, woody branches and deciduous, little-divided green branchlets, thin and usually flexible Male flower a single stamen enclosed in bud by 1 or 2 (anterior and posterior) concave or hood-shaped membranous perianth-segments which break off at base as stamen develops; mature anther exserted Flowers grouped into unisexual inflorescences with closely spaced alternating whorls of bracts similar to scale-leaves; male spikes cylindrical, terminating deciduous branches singly, rarely also axillary and shortly stalked on persistent branches; female heads shortly-stalked or subsessile, ovoid or globular, axillary along persistent branches; both male and female flowers sessile and solitary in axil of each bract of whorl; pair of lateral bracteoles enclosing each flower Infructescence cone-like, globular, ovoid or cylindrical, ± woody, formed by enlargement and thickening of accrescent bracts and bracteoles of the individual flowers, the latter usually the more elongated and forming pairs of valves enclosing the true fruit and opening when ripe Fruit a samara, very much laterally compressed, apex produced into large ± translucent wing with 1 longitudinal nerve Trees or shrubs, monoecious or more often dioecious Leaves on both kinds of branches reduced to whorls of small triangular scales united at base; midribs decurrent to lower node giving a ribbed or grooved appearance to internode; on persistent stems leaves becoming separate as stem thickens; leaf-whorls, and therefore also ribs, alternating at consecutive nodes Branches of two kinds: normal, woody branches and deciduous, little-divided green branchlets, thin and usually flexible Male flower a single stamen enclosed in bud by 1 or 2 (anterior and posterior) concave or hood-shaped membranous perianth-segments which break off at base as stamen develops; mature anther exserted Flowers grouped into unisexual inflorescences with closely spaced alternating whorls of bracts similar to scale-leaves; male spikes cylindrical, terminating deciduous branches singly, rarely also axillary and shortly stalked on persistent branches; female heads shortly-stalked or subsessile, ovoid or globular, axillary along persistent branches; both male and female flowers sessile and solitary in axil of each bract of whorl; pair of lateral bracteoles enclosing each flower