Diplazium fuliginosum
Diagnostic description:
Frond 1x pinnate except near apex; stipe black; pinnae adnate, narrowing from near base to apex, apex acute, margin crenate; main rachis adaxially without raised ridges; scales entire.
Rhizome:
Rhizome erect, black, with thick, wiry black roots, bearing up to 6, usually only 1 or 2 fronds.
Rhizome scales:
Rhizome scales basifix, to ca. 1 by 0.2 cm, falcate and often dark brown to black, margin entire, smooth sometimes slightly repand where two cells meet, apex truncate.
Fronds:
Fronds monomorphic, pinnate.
Stipe:
Stipe black, up to ca. 20 long, 3-6 mm thick or thicker.
Rachis:
Rachis black, adaxially channeled or broadly U-shaped, without raised flanges, insertion of pinnae not affecting the channel, with very few brown scales, pinna rachis adaxially flat.
Lamina:
Lamina ca. 30-90 by 8-14 cm, 3-7 x longer than wide, widest at 1/3 - ½ from base, dark green to blackish above (also when fresh), lighter below, often with contrasting dark veins and a dark margin.
Pinnae:
basal pinna reduced, 1-4 cm long, 0.2-0.8 the length of the largest pinnae, up to ca. 4 cm remote, largest pinnae 4-8 by 1.3-2 cm, with truncate, slightly asymmetric, base; narrowing from close to base to apex, apex acute, margin irregularly and weakly crenate.
Sori:
Sori dark brown, mostly on the distal ½ - 1/3 of frond or pinnae, on unbranched veins or following the acroscopi branch of forked veins. Indusia blackish with a narrow brown margin. Spores pale brown with broad crisped pale anastomosing wings.
Distribution:
Philippines: Leyte; Borneo: Sabah (Kinabalu); Papua New Guinea, New Ireland.
Ecology:
Terrestrial in forest, often in gullies, 1500 – 3000 m or higher.
Notes:
This is one of Price's "unusual Diplazia", and can fairly easily be recognized from the others by the thick stipe, the fully once-pinnate lamina and the dense dark scales.
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