Stems ascending to erect; scales dark brown, ovate to lanceolate, margins dentate. Petiole 15--45 cm. Blade deltate-lanceolate, pinnate-pinnatifid, 20--36 × 8--22 cm, broadest at or just above base, acuminate at apex. Pinnae lanceolate-oblong, inequilateral, base cuneate basiscopically, truncate acroscopically, apex acuminate, lobed halfway or more toward costa; basal acroscopic segments of basal pinnae free, margins serrate. Veins pinnate, lateral veins simple or sometimes forked. Sori elongate, straight, single or double, indusiate; indusia vaulted, thin, erose.
Moist wooded slopes; lowland; very rare; 0--100 m; La.; Mexico; Central America; n South America.
Central and South American species closely related to Diplazium lonchophyllum , including D . cristatum (Desrousseaux) Alston, D . drepanolobium A. R. Smith, and D . werckleanum H. Christ, are in need of monographic work (R. G. Stolze 1981; A. R. Smith 1981; J. T. Mickel and J. M. Beitel 1988).