Stenostomum portoricense Britton & P. Wilson

Antirhea portoricensis (Britton & Wilson) Standley
Slenostomum portoricense Britton & Wilson, Sci. Surv. Porto Rico 6: 564. 1930.
A tree 10 meters high, the branches slender, grayish-brown, glabrotis; petioles stout, glabrous, 2-8 mm. long; leaf-blades elliptic to elliptic-oblong, 6-13 cm. long, 2.5-6.5 cm. wide, obtuse or rounded at the apex or obtusely short-acuminate, narrowed or obtuse at the base, subcoriaceous, dull, the costa subimpressed on the upper surface, prominent beneath, the lateral nerves about 7 on each side, prominulous beneath, very slender, almost straight, inconspicuous, the veins obsolete; cymes slender-pedunculate, with 2 or 3 or more branches, the branches slender, recurved, glabrous, 1.5-3.5 cm. long, with rather numerous and remote flowers; fruit ellipsoid or globose-ellipsoid, 7-9 mm. long, 5-6 mm. thick, 4-celled.
Type locality: Candelaria. Porto Rico. Distribution: Limestone hills, northern Porto Rico.

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

Stenostomum portoricense là một loài thực vật có hoa trong họ Thiến thảo. Loài này được Britton & P.Wilson miêu tả khoa học đầu tiên năm 1930.