轴果蕨科 zhou guo jue ke
He Zhaorong (和兆荣); Masahiro Kato
Plants terrestrial or lithophytic, evergreen, medium-sized. Rhizome erect or creeping, apex and base of stipes scaly; scales brown, lanceolate, entire, long; fronds caespitose, rarely distant or approximate. Fertile fronds up to 2 m; stipe pale stramineous, rarely red-brown, usually as long as lamina, base not thickened, with sparse scales, upward glabrous throughout. Lamina deltoid or ovate-deltoid, herbaceous, glabrous, pinnate lobes 2- or 3-pinnate or ultimate pinnules pinnate, acuminate at apex. Pinnae alternate, ascending, stipitate, pinnules anadromous, acuminate at apex, base asymmetrical or subsymmetrical. Lobes anadromous, obtuse, usually asymmetrical at base basiscopic, serrate or crenate of ultimate pinnules at margin, sometimes entire. Veins free, prominently, lateral veins mostly forked or pinnate on ultimate pinnules, rarely simple. Costae slightly shallowly grooved adaxially, bilateral margin slightly protuberance. Sori shortly linear, or slightly lunate, solitary on acroscopic veinlets of ultimate pinnules base, usually in 1 line per lobe, 1 or 2 pairs per lobes with pinnate veins, close to ultimate pinnules or midrib of lobes, in parallel lines with each other. Sori and indusia similar, solitary, thickly membranous, slightly swollen, pale gray or gray-green at first, then mostly becoming pale brown, entire, persistent, Spores 2-sided, semicircular in equatorial plane view. Spores perispore prominent, slightly hyaline, rough, with regular or irregular filiform ornamentation, circular projection, or rarely broad flakelike folds. x = 40.
One genus and seven species: mainly distributed in subtropical and tropical areas of China, east to Japan, the Philippines, south to Vietnam and Indonesia (Sumatra); five species (three endemic) in China.
Based on molecular evidence that Rhachidosorus does not form a monophyletic group with Athyriaceae (cf. Sano, R. et al. 2000. Molec. Phylogen. Evol. 15: 403–413), Zhang proposed the family Rhachidosoraceae X. C. Zhang (Christenhusz et al. 2011. Phytotaxa 19: 7–54).
Chu Wei-ming, Wang Zhong-ren, Hsieh Yin-tang & He Zhao-rong. 1999. Athyriaceae (Rhachidosorus). In: Chu Wei-ming, ed., Fl. Reipubl. Popularis Sin. 3(2).
轴果蕨属 zhou guo jue shu
Morphological characters and geographic distribution are the same as those of the family.
1a. Stipe and rachis red-brown; pinnules asymmetrical ......................................... 1. R. mesosorus
1b. Upper part of stipe and rachis stramineous; pinnules symmetrical or subsymmetrical.
2a. Pinnules and pinnule lobes contiguous or approximate, lobes truncate, entire or shallowly crenate 2. R. truncatus
2b. Pinnules and pinnule lobes (particularly basal ones) apart, lobes orbicular, crenate.
3a. Pinnule lobes and secondary pinnules usually oblong, rarely ovate ............... 3. R. consimilis
3b. Pinnule lobes and secondary pinnules ovate.
4a. Basal pinnae wider than upper ones, narrowly ovate, relative length to width ca. 2:1, surface of spores with few irregular, broadly flakelike folds .................................................. 4. R. blotianus
4b. Basal pinnae similar to upper ones, broadly lanceolate, relative length to width ca. 3:1, surface of spores with sparse irregular flakelike and filiform protuberances ................... 5. R. pulcher
轴果蕨 zhou guo jue
Asplenium mesosorum Makino, Bot. Mag. (Tokyo) 12: 120. 1898; Athyrium mesosorum (Makino) Makino; Diplazium mesosorum (Makino) Koidzumi.
Rhizome long or shortly creeping, apex and stipe base densely scaly; scales brown, lanceolate, clathrate, membranous, hyaline, with long multicellular marginal hairs; fronds approximate. Fertile fronds 50–60 cm; stipe pale castaneous or red-brown, shiny, 20–40 cm, 2–3 mm in diam., upward glabrous; laminae 2- or 3-pinnate with pinnules or ultimate pinnules pinnatipartite, broadly ovate to deltoid, 30–40 × 15–25 cm at base, apex abruptly narrowed, acuminate; pinnae ascending, narrowly ovate to broadly lanceolate, apex long acuminate; basal pair largest, 15–20 ´ 4.5–10 cm, with stalk 2–4 cm; pinnules 8–15 pairs, alternate, subspreading, ovate-deltoid, base asymmetrical (acroscopic base subtruncate, basiscopic base broadly cuneate), lower pinnules stalked, usually basiscopic pinnules longer than acroscopic pinnules, ca. 8 ´ 3 cm, pinnatilobate or nearly pinnate; pinnule lobes slightly oblique, ovate-deltoid or oblong, connate to each other with narrow wings, pinnatilobate to pinnatipartite or nearly pinnate, apex rounded-obtuse; ultimate pinnules obtuse apex, shallowly toothed at margin. Veins prominent on both sides, pinnate, veinlets simple or forked; lamina green or brown-green, thinly herbaceous or submembranous, glabrous on both surfaces; lower part of rachis and costae pale castaneous or red-brown, upper part stramineous, shiny. Sori lunate, narrowly elliptic, single and costular on basal acroscopic veinlets; indusia pale green when young, becoming pale brown when mature; perispore with irregularly warty ornamentation.
Wetlands in forest understories; 100–1000 m. Hubei (Badong), Jiangsu (Yixing), Zhejiang (Linan) [Japan, Korea].
The type is from Japan.
云贵轴果蕨 yun gui zhou guo jue
Rhachidosorus subfragilis Ching.
Rhizome erect; fronds caespitose. Fertile frond up to 1.6 m; stipe castaneous-brown at base, upward stramineous, shiny, up to 70 cm, base with dense brown lanceolate scales, upward glabrous; lamina 2- or 3-pinnate with pinnules or secondary pinnules pinnatilobate, deltoid, up to 1 m × 80 cm, glabrous, acuminate at apex; pinnae up to 20 pairs, all stalked, stalk of lower pinnae ca. 2 cm, slightly ascending, basal 2 pairs of pinnae largest, broadly lanceolate or narrowly elliptic-lanceolate, up to 40 ´ 14 cm, base subsymmetrical, apex acuminate, shortly caudate; upper pinnae lanceolate; pinnules up to 15 pairs, alternate, spreading, up to 10 ´ 3 cm, with stalk ca. 4 mm, narrowly winged, pinnules on basiscopic side longer than acroscopic, apex shortly acuminate to rounded; pinnule lobes up to ca. 10 pairs, oblong or ovate, up to 15 × 8 mm, pinnatilobate to pinnatifid with 4 or fewer lobes, apex rounded or truncate and entire or slightly repand. Veins prominent on abaxial side, pinnate, veinlets 1 or 2 pairs in ultimate lobes, mostly simple, occasionally forked. Lamina green abaxially, usually brown adaxially, herbaceous when dry, rachis and costae pale stramineous, shiny. Sori and indusia lunate, usually 1 per lobe, costular. Perispore with dense irregular warty ornamentation.
* Under bushes, calcareous rock crevices; 600–1500 m. Guangxi (Napo), Guizhou (Anlong, Ceheng, Libo), Yunnan (Maguan, Malipo, Xichou).
The type is from Guizhou (Ceheng).
喜钙轴果蕨 xi gai zhou guo jue
Athyrium fragile Tardieu (1932), non Sprengel (1804); Rhachidosorus blotianus Ching (1976), not Ching (1964).
Rhizome erect, up to 4 cm (including remaining stipe bases); fronds caespitose. Fertile frond up to 2 m; stipe yellow-brown at base, upward stramineous, up to 1 m, up to 1 cm in diam. at base, base with dense yellow-brown lanceolate scales, upward glabrous; lamina 2- or 3-pinnate, deltoid, as long as stipe, apex long acuminate; pinnae up to 25 pairs, basal 2 pairs largest, up to 50 ´ 15 cm, broadly lanceolate, pinnatilobate and caudate, with stalk up to 3 cm, apex long acuminate; pinnules up to 20 pairs, alternate, spreading, anadromous, up to 8 ´ 2.5 cm, broadly lanceolate, symmetrical or base slightly asymmetrical, with stalk up to 5 mm, apex acuminate, long caudate; pinnule lobes up to 8 pairs, ovate or oblong, ca. 1 cm ´ 7 mm, base asymmetrical, wider acroscopically, cuneate at basiscopic base, shallowly lobed, apex rounded; secondary lobes of pinnule lobes less than 5 pairs, contiguous, oblique, truncate to rounded. Veins pinnate, veinlets less than 5 pairs per pinnule lobe, 2 pairs in secondary lobe, others forked or simple. Lamina green, paler abaxially, herbaceous when dry, rachis stramineous, glabrous. Sori slightly lunate, oblique, costular to 5 pairs in pinnule lobe; indusia pale brown when dry. Perispore surface with irregular warty ornamentation.
* Under bushes in calcareous areas; 600–1800 m. Guizhou (Anshun, Libo), Sichuan (Emei Shan), Yunnan.
The type is from Sichuan (Emei Shan).
脆叶轴果蕨 cui ye zhou guo jue
Athyrium fragile Tardieu (1932), non Sprengel (1804).
Rhizome robust, erect, brown, up to 3 cm in diam. (including remaining stipe bases), woody, apex scaly, scales brown-lanceolate. Fertile fronds up to 2.2 m; stipe brown or castaneous-brown at base, upward gradually pale stramineous, up to 1.1 m, up to 7 mm in diam. at base; lamina 3-pinnate with secondary pinnules lobed, deltoid, up to 1.25 × 1 m at base, apex long acuminate; pinnae 9 or 10 pairs, ascending, mostly alternate, with stalk up to 3.5 cm; basal 1 or 2 pairs of pinnae narrowly deltoid or narrowly ovate-lanceolate, up to 70 ´ 30 cm, apex caudate, long acuminate; pinnules up to 19 pairs, alternate, stalked (stalk up to 1 cm), ascending, lanceolate, lower pinnules up to 16 ´ 5 cm, pinnatisect, apex caudate, long acuminate and roughly serrate; pinnule lobes up to 10 pairs, ovate, pinnatilobate to pinnatifid, connate to each other with narrow wings, spreading, base asymmetrical, broadly cuneate, acroscopic secondary lobes larger, roughly crenate at apex; secondary pinnule lobes less than 5 pairs, shallowly crenate. Veins visible abaxially, pinnate in pinnule lobe, veinlets forked or simple. Lamina mostly brown, paler abaxially, herbaceous or thinly herbaceous when dry, rachis stramineous, shiny. Sori shortly linear or slightly lunate, single in secondary lobes or 1 or 2 pairs in basal ones, costular; indusia light gray when young, pale brown when mature, shortly linear or lunate. Perispore with mostly broad flakelike folds.
Understories of evergreen broad-leaved forests; 700–1400 m. Guangxi (Baise), Guizhou (Guiding), Yunnan [Vietnam].
The type is from N Vietnam.
台湾轴果蕨 tai wan zhou guo jue
Diplazium pulchrum Tagawa, Acta Phytotax. Geobot. 4: 144. 1935.
Rhizome erect, up to 4 cm in diam. (including remaining stipe bases), apex densely scaly; scales yellow, lanceolate or linear, up to 1 cm, membranous, entire. Fertile frond up to 2 m; stipe brown at base, upward stramineous, up to 1 m, up to 5 mm in diam. at base, sparse scaly, scales similar to those on rhizome, upward subglabrous; lamina pinnate to nearly 3-pinnate, deltoid, up to 1 m ´ 80 cm, apex acuminate; pinnae ca. 15 pairs, alternate, ascending, usually narrowly ovate-lanceolate, base slightly asymmetrical with anadromous pinnules shorter, apex shortly caudate; basal 1 or 2 pairs of pinnae largest, up to 50 ´ 20 cm, stalked (stalk 2–3 cm), nearly 2-pinnate; pinnules spreading, separate, deltoid-lanceolate, up to 11 ´ 4 cm, asymmetrical, acroscopic lobes larger, lower pinnules stalked, stalk short, narrowly winged, pinnatifid to pinnatisect, or nearly pinnatisect, apex caudate, long acuminate; pinnule lobes up to 10 pairs or more, basal lobes mostly ovate, other lobes elliptic or oblong, base slightly asymmetrical, acroscopic base larger, pinnatifid to pinnatisect, or only sparsely crenate, apex obtuse. Laminae green or pale green, slightly deeper colored adaxially, thinly membranous when dry, rachis and costae stramineous. Sori mostly narrowly elliptic, rarely lunate, costular, oblique; indusia pale green when young, pale brown. Perispore with flattened tuberculate ornamentation.
* Valleys, understories of evergreen broad-leaved forests, among shrubs; 500–1400 m. Taiwan, Yunnan (Fugong, Yinjiang).
The type is from Taiwan (Hualian).
Rhachidosorus pulcher is very similar to R. blotianus in the morphology of lamina, pinnules and pinnule lobes, so the two species have usually been considered conspecific; however, they differ in spore ornamentation.