Sphaeropteris brunei (Christ) R. Tryon

Cyathea brunei Christ, Bull. Herb. Boiss. II. 4 : 497. 1904
Cyathea caesia Christ, Bull. Herb. Boiss. II. 7 : 272. 1907.
Caudex erect, 3-4 meters high, 30 cm. or more in diameter at the summit, there very densely paleaceous, without definite scars, the old fronds pendent and sheathing the caudex ; fronds 3.5-4 meters long, borne in a nearly erect crown ; stipe 5 cm. in diameter at the base, dark purplish-brown below, sparsely tuberculate beneath a very dense covering of delicate flaccid yellowish-brown scales, these (paler with age) up to 6 cm. long and 3.5 mm. broad, linear-lanceolate, very long-attenuate, widely spreading, underlaid by successively smaller scales, the innermost greatly reduced, dark-brown, subulate, conspicuously spinescent-ciliate, subpersistent; lamina about 3 meters long, 1.7 meters broad, broadly ovate, abruptly acuminate, the primary rachis stout, dull -yellowish or brownish, glabrescent, when young densely paleaceous, the scales small, dark-brown, closely entangled, long spinescent-ciliate, usually persistent in a long tuft at the base of the pinnae and extending throughout the stout yellowish secondary rachis, there deciduous or at the base of the pinnules subpersistent ; pinnae mostly alternate, the lowermost subopposite and somewhat reduced (40 cm. long), long-petiolate (6-9 cm.); characteristic pinnae 70-100 cm. long, 20-30 cm. broad, petiolate (2-5 cm.), oblong-lanceolate from a broad base, acuminate, caudate • pinnules 'about 40 pairs, 10-15 cm. long, 1.5-2.5 cm. broad, narrowly oblonglanceolate from a broader base, long-acuminate, cut to the costa, the lowermost short-p etiolate (3 mm. or less) and distant, those above gradually closer, sessile; costae sparingly clothed with laciniate or long spinescent-ciliate deciduous fulvous scales, these extending to the costules; segments mostly linear-oblong, falcate, obtuse, the fertile ones narrower (1-1.4 cm. long, 2.5-3 mm. broad) and apart, about 25-30 pairs, coriaceous, the margins somewhat thickened, subrevolute, entire or (in fertile segments) obscurely crenate, the leaf-tissue minutely but densely whitish granulose-ceraceous below, also minutely glandular-setose ; veins concealed, 10 or 11 pairs, onceor twice-forked; sori medial, completely covering the segment; indusium globose, firm, whitish or with age prui nose-brownish, bursting into several large infiexed persistent saccate lobes; receptacle brownish, elevated, relatively small, squamulose-pilose.
Type locality : Costa Rica.
Distribution : Not uncommon in the humid interior mountain region of Costa Rica, altitude 1450 to 2000 meters.

Sphaeropteris brunei là một loài thực vật có mạch trong họ Cyatheaceae. Loài này được (H. Christ) R.M. Tryon miêu tả khoa học đầu tiên năm 1970.