Nephrolepis davallioides (Sw.) Kunze - Fig, 1846

Hovenkamp PH & Miyamoto F, 2005, A conspectus of the native and naturalized species of Nephrolepis (Nephrolepidaceae) in the world, Blumea 50, pp. 279-322 : 298-299

7. Nephrolepis davallioides (Sw.) Kunze - Fig . 1c; Map 5; Plate 2b

Nephrolepis davallioides (Sw.) Kunze (1846) 460 ; Baker (1867) 302; Holttum (1954) 634; Tagawa & K. Iwats. (1985) 172. - Ophioglossum acuminatum Houtt. (1783) 49 . - Aspidium davallioides Sw. (1801) 33 ; Blume (1828) 148. - Nephrodium davallioides (Sw.) Desv. (1827) 254 . - Nephrolepis acuminata (Houtt.) Kuhn (1869) 286 ; Backer & Posth. (1939) 93; Holttum (1968) 378 (nom. illeg. non C. Presl 1836). - Type: Plate in Houttuyn.

Nephrodium deparioides Bory (1833) 59. - Type: Belanger s.n. ( P), Java.

Nephrolepis pendula de Vriese (1846) 8 (nom. illeg. non J. Sm. 1842a). - Type: Reinwardt 1564 ( L), Celebes.

Nephrolepis serrata Alderw. (1918) 34 . - Type: Kornassi 626 ( BO), Ceram.

Habit, rhizome morphology. Plants forming tufts of 4 or 5 fronds. Runners 1-2 mm thick, branching angle narrow. Scales on runners very sparse to dense, appressed. Tubers absent. Fronds 110-210 cm long (or more), 26-38 cm wide, stipe 23-45 cm long. Lamina base truncate, tapering over 25-30 cm, basal pinnae 4-12 cm long, 3.5-12 cm distant, middle pinnae slightly to distinctly falcate. Sterile pinnae 14-18 by 1.7-2.4 cm, base slightly unequal, basiscopic base cuneate, truncate or rounded, acroscopic base emarginate or slightly cuneate, not auricled, margin in basal part crenate to serrate, towards apex more distinctly serrate, apex acuminate or caudate with cauda to 3 cm long. Fertile pinnae 14-28 by 1.1-1.4 cm, base often more narrowly cuneate and margin more deeply incised (to 2-3.5 mm) than the sterile pinnae. Indument. Basal scales peltate, appressed, 3 by 1 mm, central part dark brown, shining, margin in basal part hyaline, fmbriate, in acumen fmbriate, near apex entire, marginal glands present around the base. Rachis scales dense, with a well-developed protracted acumen, spreading or squarrose, hyaline, acumen ciliate (acumen of larger scales composed of a long, sclerified subular protrusion). Scales on lamina usually persistent, sparse, present on lower surface only. Hairs on lamina absent, costa absent. Sori marginal (on teeth), 28-50 pairs on fully fertile pinnae, round, not impressed. Indusium reniform, with narrow sinus, attached at sinus.

Distribution - Restricted to Malesia: Peninsular Thailand, Peninsular Malaysia, Sumatra, Celebes, Borneo, Java, New Guinea.

Habitat & Ecology - Common in forests at middle elevations (800-1600 m), rarely lower (200 m) or higher (up to 2100 m). Usually in forest, terrestrial, often on roadside or stream banks; more often epiphytic, often on trunks.

Note - Typical specimens have deeply dissected fertile pinnae, with sori nearly marginal, on separate teeth, and the lamina between the sori cut to c. 1/2. However, many specimens (especially from the eastern part of the distribution area) have less deeply divided pinnae, and such specimens can easily be confused with other species. They can best be distinguished by the rachis indument, which consists of scales with a narrow, dark acumen, sometimes needle-like, often directed sideways towards the upper surface. Hairs are sometimes present on the upper surface of the costae, usually near the base only, situated on short, narrow lines of paler tissue.