Plants in thin mats, dark- to yellowish-green, with an oily sheen when wet. Stems to 3 cm, 1--3 mm wide, prostrate, often radiculose ventrally. Leaves loosely imbricate, usually concave, smooth, symmetric, 1.0--2.5 × 0.5--1 mm, ovate to broadly ovate-lanceolate, acuminate or filiform-acuminate, often twisted at apex, margins plane, serrulate to serrate beyond leaf middle, serrulate to entire proximally; costa short and double, one branch extending 1/3--1/2 length of leaf, rarely lacking; cells smooth; median cells 75--120 × 7--12 µm; alar cells 12--48 × 10--22 µm, quadrate to rectangular, in 2--several rows with 5--12 cells in marginal row. Sexual condition dioicous. Perichaetia large, numerous, bracts lanceolate to ovate-lanceolate, acuminate to sharply acuminate. Perigonia and sporophytes unknown in North America.

Calcareous soil and rock, rarely over exposed tree roots; 0--300 m; Ala., Fla., Tenn.; Asia.

Taxiphyllum cuspidifolium is distinguished by its julaceous to subjulaceous plants with an oily sheen when wet and by its loosely imbricate, erect-spreading, concave leaves with plane margins and acuminate to filiform-acuminate apices. It is rare in North America where it is known from only one locality in Alabama (Bibb Co.), four in Florida (Alachua, Citrus, Jackson and Walton counties) and two in Tennessee (Anderson and Montgomery counties). It has often been confused with Plagiothecium cavifolium (Bridel) Z. Iwatsuki, which has a more northern distribution. For microscopic differences between the genera Plagiothecium and Taxiphyllum see the discussion under T. alternans.