Stenostomum sintenisii (Urb.) Britton & P. Wilson

Antirhea sintenisii Urban, Symb. Ant. 1: 438. 1899
Slenostomum Sintenisii Britton & Wilson, Sci. Surv. Porto Rico 6: 238. 1925.
A tree about 15 meters high, with yellowish wood, glabrous except the flowers and stipules, the branches brownish or grayish, sparsely and minutely lenticellate, not resinous; stripules triangular-oblong, 5-7 mm. long, early deciduous, minutely pilosulous near the base; petioles stout, 3-6 mm. long; leaf-blades oblong, oblanceolate-oblong, or narrowly elliptic-oblong, 5-10 cm. long, 1.5-4 cm. wide, broadest at or above the middle, obtuse or very obtuse, obtuse or acute at the base, coriaceous, subconcolorous, the costa impressed above, prominent beneath, the lateral nerves prominulous or plane beneath, 6-10 on each side, ascending at an angle of 60-70°, very slender, almost straight, the veins obsolete, the margin plane; cymes bifid, the branches 2-4 cm. long, with 16 or fewer flowers, the peduncles 1.5-3 cm. long, the flowers sessile, biseriate; hypanthium minutelj^ pilose, the calyx 1.5 mm. long, minutely 4-lobate; corolla ochroleucous, 6 mm. long, minutely appressed-pilosulous outside, the 4 lobes roundedobovate, half as long as the tube, the tube glabrous within; anthers included; stigma-lobes 2, rounded; fruit elliptic-oblong, 8-10 mm. long, 4-5 mm. thick, 2-celled.
Type locality: Rocky mountain forests, Los Angeles, Porto Rico. Distribution: Wet forest at lower and middle elevations, Porto Rico.

Stenostomum sintenisii, synonym Antirhea sintenisii, is a species of plant in the family Rubiaceae. It is endemic to Puerto Rico.

Stenostomum sintenisii là một loài thực vật có hoa trong họ Thiến thảo. Loài này được (Urb.) Britton & P.Wilson miêu tả khoa học đầu tiên năm 1925.