Taxon Details: Megalastrum canescens (Kunze ex Mett.) A.R.Sm. & R.C.Moran
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Combination for Megalastrum canescens (Kunze ex Mett.) A.R. Sm. & R.C. Moran
Combination for Megalastrum canescens (Kunze ex Mett.) A.R. Sm. & R.C. MoranFamily:
Dryopteridaceae (Pteridophyta)
Dryopteridaceae (Pteridophyta)
Scientific Name:
Megalastrum canescens (Kunze ex Mett.) A.R.Sm. & R.C.Moran
Megalastrum canescens (Kunze ex Mett.) A.R.Sm. & R.C.Moran
Primary Citation:
Amer. Fern J. 77(4): 127. 1987
Amer. Fern J. 77(4): 127. 1987
Accepted Name:
This name is currently accepted.
This name is currently accepted.
Synonyms:
Phegopteris canescens Kunze ex Mett.
Nephrodium villosum var. canescens (Kunze ex Mett.) Baker
Ctenitis canescens (Kunze ex Mett.) C.V.Morton
Phegopteris cana Mett.
Phegopteris mollivillosa Fée
Phegopteris canescens Kunze ex Mett.
Nephrodium villosum var. canescens (Kunze ex Mett.) Baker
Ctenitis canescens (Kunze ex Mett.) C.V.Morton
Phegopteris cana Mett.
Phegopteris mollivillosa Fée
Description:
by: R.C. Moran, J. Prado, and P.H. Labiak
Lectotype: (designated by Moran et al, 2009): Brazil. Bahia: Castelnovo, 1836, Blanchet 2454 (NY; duplicates: B-n.v., GH, K, P).
Description: Leaves to 2 m long; scales of petiole bases ca. 1 × ca. 0.1 cm, lanceolate, sparsely denticulate, brown to dark brown, sometimes with blackish denticulate margins (this color often absent on scales on the distal portion of petiole); laminae 1-2 m long, 2-pinnate-pinnatisect at base, 2-pinnate medially; basal pinnae ca. 0.4 m long, stalks to 3.5 cm long, strongly inequilateral, pinnules acroscopically reduced toward pinna bases; pinna rachises abaxially glandular, pubescent and sparsely scaly (scales sometimes apparently absent), glands ca. 0.1 mm long, hairs ca. 1 mm long, 5-7-celled, scales ca. 1.5 mm, non-bullate, ovate-lanceolate, subentire, apices long-acuminate; adaxially apparently non-glandular, densely pubescent, hairs ca. 1.2 mm long, 5- or 8-celled; costules glandular, glands 0.1 mm long, pubescent abaxially with two sizes of hairs, longer ones ca. 1 mm long, 3-5-celled, shorter ones ca. 0.2 mm long, 1- or 2-celled, sparsely scaly, scales to 1 mm long, uniseriate, appressed, brown; laminar tissue between veins abaxially glandular and pubescent, glands ca. 0.1 mm long, 1- or 2-celled, yellowish, abundant to nearly absent, hairs 0.3-0.5 mm long, 2- or 3-celled, adaxial surfaces sparsely pubescent, hairs 0.2-0.4 mm long, 1- or 2-celled, appressed; veins visible and pubescent on both surfaces, hairs on abaxial surfaces 0.4-0.8 mm long, 1-3-celled, adaxial surfaces with hairs 0.5-0.8 mm long, 3-6-celled, glandular hairs absent; lamina margins ciliate, hairs ca. 0.4-0.5 mm long, 1- or 2-celled, glandular hairs apparently absent; indusia absent.
Distribution: SE Brazil; 600-1200 m.
Comments: Megalastrum canescens is characterized by hairs ca. 1 mm long and 5-8-celled on the abaxial surfaces of the laminae, intermixed with shorter ones, up to 0.2 mm long, non-bullate scales, and lack of indusia. The petiole base scales of this species tend to have blackish margins. Superficially, this species resembles M. albidum, which see for comparison.
by: R.C. Moran, J. Prado, and P.H. Labiak
Lectotype: (designated by Moran et al, 2009): Brazil. Bahia: Castelnovo, 1836, Blanchet 2454 (NY; duplicates: B-n.v., GH, K, P).
Description: Leaves to 2 m long; scales of petiole bases ca. 1 × ca. 0.1 cm, lanceolate, sparsely denticulate, brown to dark brown, sometimes with blackish denticulate margins (this color often absent on scales on the distal portion of petiole); laminae 1-2 m long, 2-pinnate-pinnatisect at base, 2-pinnate medially; basal pinnae ca. 0.4 m long, stalks to 3.5 cm long, strongly inequilateral, pinnules acroscopically reduced toward pinna bases; pinna rachises abaxially glandular, pubescent and sparsely scaly (scales sometimes apparently absent), glands ca. 0.1 mm long, hairs ca. 1 mm long, 5-7-celled, scales ca. 1.5 mm, non-bullate, ovate-lanceolate, subentire, apices long-acuminate; adaxially apparently non-glandular, densely pubescent, hairs ca. 1.2 mm long, 5- or 8-celled; costules glandular, glands 0.1 mm long, pubescent abaxially with two sizes of hairs, longer ones ca. 1 mm long, 3-5-celled, shorter ones ca. 0.2 mm long, 1- or 2-celled, sparsely scaly, scales to 1 mm long, uniseriate, appressed, brown; laminar tissue between veins abaxially glandular and pubescent, glands ca. 0.1 mm long, 1- or 2-celled, yellowish, abundant to nearly absent, hairs 0.3-0.5 mm long, 2- or 3-celled, adaxial surfaces sparsely pubescent, hairs 0.2-0.4 mm long, 1- or 2-celled, appressed; veins visible and pubescent on both surfaces, hairs on abaxial surfaces 0.4-0.8 mm long, 1-3-celled, adaxial surfaces with hairs 0.5-0.8 mm long, 3-6-celled, glandular hairs absent; lamina margins ciliate, hairs ca. 0.4-0.5 mm long, 1- or 2-celled, glandular hairs apparently absent; indusia absent.
Distribution: SE Brazil; 600-1200 m.
Comments: Megalastrum canescens is characterized by hairs ca. 1 mm long and 5-8-celled on the abaxial surfaces of the laminae, intermixed with shorter ones, up to 0.2 mm long, non-bullate scales, and lack of indusia. The petiole base scales of this species tend to have blackish margins. Superficially, this species resembles M. albidum, which see for comparison.