Flora of Japan| Dryopteris pacifica | |
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Etymology
Pacifica is a reference to the area of the Pacific Ocean.
Description
Rhizome: suberect to erect.
Frond: evergreen, monomorphic, blade/stipe ratio: 3:1 to 1:2. Stipe: grooved, scales blackish-brown, vascular bundles: 3-7 in a c-shaped pattern. Blade: 3-pinnate, triangular, abruptly narrowed tip, dark green, glossy, papery, narrow, black, somewhat bullate (inflated) scales. Pinnae: 18 to 20 pair, alternate, strongly anadromic at the base, becoming catadromic above; pinnules downward-pointing, nearest the rachis, larger than upward ones; costae grooved above, continuous from rachis to costae; segments dentate; margins margins entire; veins free, forked. Sori: round, small, in 1 row between midrib and margin, indusium: reniform, at a sinus, sporangia: brownish. Culture
Habitat: lowland forest edge.
Distribution: Japan, Korea, China.
Hardy to -20°C, USDA Zone 6.
Distinctive Characteristics
The abruptly narrowed blade above the 10th or 11th set of pinnae is rare, but not unique; D. cystolepidota (nipponensis) has this, too, but here the lower pinnules closest to the rachis are longer.
Synonyms
Polystichum pacificum Nakai Polystichum hoolepis var. hikonensis H. Itô Dryopteris varia (L.) Kuntze var. hikonensis (H. Itô) Sa. Kurata Dryopteris hikonensis (H. Ito) Nakaike |
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Notes
Compare to This shares several characteristics with D. cystolepidota, most notably the contracted blade tip, the 3-pinnate division at the base, toothed segment margins, and dark, blackish scales on stipe and rachis. D. cystolepidota, however, differs in having the second downward-pointing pinnules of the lower pinnae longest, whereas in D. pacifica has the ones closest to the rachis longest.
Compare to Similar to D. varia, differing from it in: scales at lower portion of stipes blackish brown to black; upper pinnae rather suddenly shortened to form acuminate apex; stiff-papery, shining on the upper surface; lobes minutely toothed at margin; indusia sometimes hairy at margin. Also similar to D. bissetiana, differing from it in the margins are not reflexed.
Compare to This shares several characteristics with D. cystolepidota, most notably the contracted blade tip, the 3-pinnate division at the base, toothed segment margins, and dark, blackish scales on stipe and rachis. D. cystolepidota, however, differs in having the second downward-pointing pinnules of the lower pinnae longest, whereas in D. pacifica has the ones closest to the rachis longest.
Compare to Similar to D. varia, differing from it in: scales at lower portion of stipes blackish brown to black; upper pinnae rather suddenly shortened to form acuminate apex; stiff-papery, shining on the upper surface; lobes minutely toothed at margin; indusia sometimes hairy at margin. Also similar to D. bissetiana, differing from it in the margins are not reflexed.
