Lindsaea hamiguitanensis D.N.Karger & V.B.Amoroso, 2012

Karger, Dirk Nikolaus, Lehtonen, Samuli, Amoroso, Victor B. & Kessler, Michael, 2012, A new species of Lindsaea (Lindsaeaceae, Polypodiopsida) from Mt. Hamiguitan, Mindanao, Philippines, Phytotaxa 56 (1), pp. 15-20 : 18-19

Lindsaea hamiguitanensis D.N.Karger & V.B.Amoroso , sp. nov. ( Fig. 2 )

Type: — PHILIPPINES. Mindanao: Davao Oriental, Mount Hamiguitan , 6°44'4.16" N, 126° 9'59.88" E, 1100 m, 1 November 2009, Karger 444 (holotype PNH!, isotypes UC!, Z!) .

Lindsaea rhizomate breve repente, pinnulis alternis, remotis, utrinque circa 2–5, 1.0– 1.8 cm longis, 0.8–1.0 cm latis, non incisis, textura herbacea, colore laete virente, petiolibusque rigidis, 10–30 cm longis, quadrangularibus.

Plants terrestrial. Rhizomes short-creeping, 1.00– 1.75 mm diameter, scales ferruginous, very narrowly triangular, to 1.5 mm long. Petioles 10–30 cm long, to 4 times longer than the laminae, sharply quadrangular, dark reddish brown (proximally) to pale, with more or less well defined paler margins. Laminae triangular, 6– 13 cm long, bipinnate to (basally) tripinnate-pinnatifid, rachises reddish brown, with pale margins, sharply quadrangular. Major primary pinnae 4–6 to a side, spreading to moderately ascending, triangular, the largest (at the bases) to 6 cm long, to 4 cm wide, the proximal ones up to their width apart, the distal ones closer to each other. Distal pinnae gradually reduced, with a conform terminal pinna, costae dark green, slightly winged, adaxially sulcate. Proximal primary pinnae basally with some pinnules 1–3 cm long. Pinnules 2–5 on each side, herbaceous, light green when dry, slightly ascending, not contiguous, dimidiate-ovate to subtrapeziform (basally), the larger ones 1–1.8 cm long, 0.8–1 cm wide, 1.5–2 times longer than wide, margins continuous, rarely incised. Pinnules at lower primary pinnae shallowly incised. Distal pinnules gradually reduced, distal ones confluent with the acuminate terminal segment. Veins free, ca. 1.5 mm apart, 1- or 2-forked. Sori continuous, rarely incised on the basiscopic pinnules of the proximal primary pinnae, convex, extending 1/2 to 2/3 of the length of the pinnules along the sides of the pinnules, to 15 mm long, multinerval. Indusia coloured as the pinnules, indusial margins entire, rarely slightly erose, 0.5–0.7 mm wide, not reaching the margin by 1–1.5 times of their width. Spores trilete.

Distribution and habitat:— Known only from Mount Hamiguitan, Mindanao, Philippines, where it grows in lower montane rainforest at 1100–1200 m.

Etymology:— The species is named for the type locality.

Additional specimen examined (paratype):— PHILIPPINES. Mindanao: Davao Oriental, Mount Hamiguitan, 6°44'4.16" N, 126°9'59.88" E, 1100 m, 1 November 2009, Karger 426 ( Central Mindanao University Herbarium !, UC!, Z!) .

Figures

FIGURE 2. A–C. Lindsaea hamiguitanensis D.N.Karger & V.B.Amoroso. A. Habit. B. Rhizome scale. C. Pinnule, abaxial, showing indusium. All from Karger 444 (Z).