Trees monoecious, to 35 m tall, not suckering from roots. Trunk straight, to 70 cm d.b.h.; crown conical; bark scaly, adaxially red-brown on old trees. Ultimate branchlets usually pendu-
lous, grayish green, 10-27 cm × 0.8-0.9 mm; articles (2.5-)4-9 mm. Leaves erect and appressed to branchlets, (6 or)7(or 8) per whorl, lanceolate or triangular, 1-3 mm. Male inflorescences1-4 cm. Cones ellipsoid, 1.2-2.5 cm, grayish green or yellowish brown tomentose when young, glabrous at maturity, base and apex truncate to obtuse; apex of bracteoles slightly obtuseor acute. Samaras 5-8 mm including wing. Fl. Apr-May, fr. Jul-Oct. 2n = 18, 20*.
Subspecies 2 (1 in the flora): North America; Southeast Asia; s Pacific Islands (e to Tahiti and Samoa); Australia.
Casuarina equisetifolia L., Amoen. Acad. 4: 143. 1759.
Arboles hasta 20 m de alto, ramas jóvenes a veces escasamente blanco-puberulentas. Hojas 6 u 8 por nudo, 0.50.8 mm de largo y 0.30.4 mm de ancho en la base, a veces recurvadas y más grandes, 2.32.7 mm de largo, rojo- y blanco-puberulentas. Inflorescencias masculinas ca 3 cm de largo; inflorescencias femeninas 1.11.9 cm de largo y 1.11.5 cm de diámetro; brácteas 57 mm de largo. Fruto 58 mm de largo.
Cultivada en las zonas pacífica y atlántica; 0450 m; fl y fr todo el año; Guzmán 71, Stevens 10960; nativa de Australia, ampliamente cultivada en los trópicos.
Samaras pale brown, dull, 5–7 mm. long, to 1 mm. thick; wing 3.5–4.5 x 2–3 mm. (those from small valves smaller), whitish or pale-brown translucent, longitudinal nerve excurrent into a mucronate curved apex.
Infructescences 8–17(25) x 10–16 mm., shortly cylindrical or subglobose, ± flattened at the apex, (6)8–9(12) whorls of paired infructescence valves; valve pairs 7–8 per whorl, 1.5–3.2 mm. wide (but smaller and fewer towards apex), valves ± obovate, acute to mucronate, apices projecting by 1.5–3 mm., gap between adjacent pairs 0.5–1 mm. wide, valve backs with 2(3) longitudinal ridges (TAB. 35, fig. 3).
Female inflorescences axillary, toward the apices of younger persistent branches, scattered or densely clustered, often on same branches as male inflorescences; heads 3–5 mm. long, ovoid or subglobose; stalk 3–10 mm. long; bracts as for the male inflorescences; stigmas exserted by 3–4 mm., red.
Male inflorescences abundant on deciduous branchlets (rare on persistent branches), 10–30(40) x 1.2–2 mm. (width excluding exserted anthers), cylindrical, tapering gradually into a short sterile basal part; whorls of bracts 15–25; bracts c. 7 per whorl, fewer near the base, appressed, 1.1–1.8 x 0.4–0.5 mm., pubescent outside; bracteoles 0.7–1 x 0.3 mm., ovate, acute, erose-dentate-ciliate in upper one-third; perianth segments 2, up to 0.7 x 0.4 mm., rounded, membranous; filaments exserted by 1.5 mm.; anthers 0.8–1 mm. long, brownish.
Deciduous branchlets numerous, especially toward the apices of the persistent branches, (0.4)0.5–0.7 mm. in diam., 7–8-ribbed; scale leaves (6)7–8 per whorl, greenish or straw-coloured, free part c. 0.5–0.7 mm. long, appressed, thinly chartaceous, glabrous, margin ciliate.
Youngest persistent branches with internodes usually 1.5–2.5 mm. long; scale leaves (6)7–8 per whorl, greenish or straw-coloured, united at base into a short tube c. 1 mm. long, free part 2–3 mm. long, much reflexed, thickly chartaceous, pubescent.
Tree 7–25 m. tall, monoecious; sterns stout, up to c. 30 cm. diam. breast height, sometimes several, bark grey-brown.
Lower branches stout, spreading, uppermost whippy and ± pendent. Deciduous branchlets arising in abundance from persistent stems especially towards apices, 0.5–0.7 mm. in diameter, bright green with 7–8 slightly paler prominent ribs; scale-leaves in whorls of (6–)7–8, small, adpressed, thinly chartaceous, pale green or straw-coloured, united at base into short tube up to 1 mm. long, free part (0.4–)0.5–0.7 mm. long, (0.2–)0.3 mm. wide, glabrous, margin with cilia similar to but shorter than those on persistent stem-leaves and continuing as a rather inconspicuous fringe of hairs along centre of grooves between stem-ribs.
Male inflorescences abundant on deciduous branches (rare on persistent branches), 10–30(–40) mm. long, 1.2–2 mm. in diameter (excluding exserted anthers), tapering gradually into short sterile basal region; whorls of bracts 15–22; bracts usually 7 per whorl or less near base, ± adpressed, mucronate, straw-coloured and chartaceous, up to 1.1–1.8 mm. long, 0.4–0.5 mm. wide, glabrous inside, margin and outer surface with hairs as on scale-leaves; bracteoles membranous-scarious, ovate, 0.7–1 × 0.3 mm., apex acute and apical third of margin erose-dentate-ciliate. Perianth of 2 segments up to 0.7 mm. long, 0.4 mm. wide, membranous, rounded. Filaments exserted up to 1.5 mm. from bracts; anthers 0.8–1 mm. long, brownish, mostly maturing and exserted at same time.
Bark dark grey or deep brownish, rough or smooth, lenticels usually visible or prominent on younger twigs on which are usually also present white remains of leaf-whorls splitting into longitudinal strips often with quite sharp recurved apices and peeling off with age to leave a ring of transverse scars and cracks at each node.
Youngest persistent stems with internodes usually 1.5–2.5 mm., rarely 8 mm. long, and whorls of (6–)7–8 scale-leaves, these straw-coloured and thickly chartaceous, extremely reflexed, free part 2–3 mm. long, 0.4 mm. wide, narrowly triangular with thick excurrent midrib, margin with numerous white or pale cilia often nearly 0.2 mm. long, similar hairs dense or sparse on adaxial surface especially midrib and more sparse on abaxial surface, midrib glabrous.
Female inflorescence axillary towards apices of younger persistent branches, scattered or densely clustered, often on same branches as ♂ and/or mature fruits; heads ± well-defined, ovoid or subglobose, 3–5 mm. long, stalk 3–10 mm.; bracts similar in shape, size, colour and pubescence to those of ♂. Stigmas exserted up to 3–4 mm., red.
Samaras varying in size, 5–7 mm. long but those from smaller valves rather smaller; wing usually 3.5–4.5 mm. long, 2–3 mm. wide, whitish or pale brown translucent, longitudinal nerve excurrent into mucronate curved apex; seed-bearing basal part flattened-ovoid, 1.5–2.5 mm. long and wide, up to 1 mm. thick, pale straw-coloured or rarely light brown, glossy but surface not shiny since roughened by minute ± longitudinal patterning of wavy raised lines.
Infructescences shortly cylindrical or subglobose with flattened apex, sparse, scattered or densely clustered, 8–17(–25) mm. long, 10–16 mm. in diameter; whorls of paired infructescence-valves (6–)8–9(–12), alternating; valves usually 7–8 per whorl, up to 1.5–3.2 mm. wide, but size and number usually less towards apex; valve-backs with 2 longitudinal ridges and densely red-brown pubescent especially at margins and towards tip, inner surfaces glabrous or pubescent at tip; valves not much thickened, ± obovate, apices acute often mucronate, projecting 1.5–3 mm. above rest of surface, valve-pairs separated from adjacent pairs by gap of 0.5–1 mm.; bracts between valves with free ± acute apex up to 1 mm. long.
|Beach she-oak, coast she-oak, casuarina, Australian-pine, horsetail casuarina|