|
4. Metathelypteris (H. Itô) Ching, Acta Phytotax. Sin. 8: 305. 1963.
凸轴蕨属 tu zhou jue shu
Authors: Youxing Lin & Kunio Iwatsuki
Thelypteris sect. Metathelypteris H. Itô in Nakai & Honda, Nov. Fl. Jap. 4: 137. 1939.
Plants small to medium-sized, terrestrial. Rhizomes short, decumbent, ascending or erect, rarely long creeping, covered with brown lanceolate scales and glaucous short hairs or subglabrous. Fronds approximate or clustered; stipes ± dark brown at bases, distally stramineous, glabrous or sparsely hairy; laminae oblong, lanceolate, or ovate-triangular, pinnate-pinnatifid, rarely tripinnate, if latter then pinnules separated from each other, never connected with narrow wing along costae, apices acuminate and pinnatifid. Laminae herbaceous or thinly herbaceous, when dry usually green, both surfaces ± with grayish white unicellular (rarely multicellular) acicular hairs, hairs denser along rachises and costae, pinnae usually glandless abaxially, rarely orange-red spherical glandular, costae rounded and raised adaxially, never grooved. Veinlets pinnate, simple or forked, oblique distally, not reaching margins. Sori small, orbicular, attached above middle of veinlets; indusia medium-sized, orbicular-reniform, each attached at a sinus, membranous, usually green, when dry grayish yellow or brownish, persistent. Spores bilateral, perispores corrugate, usually foveolate; exospore with finely reticulate surfaces. x = 35.
About 12 species: S Asia, S China to Japan, Madagascar, Malesia; 11 species (five endemic) in China.
The following taxon is excluded from the present treatment, pending further research: Metathelypteris glandulosa H. G. Zhou & H. Li (Acta Bot. Yunnan. 14: 34. 1992), described from Guangxi.
|
|
|
|
| 1 |
Pinnae with orange-red spherical glands or eglandular abaxially, costae with grayish white multicellular acicular hairs abaxially |
|
(2) |
| + |
Pinnae without orange-red spherical glands abaxially, costae with grayish white unicellular acicular hairs or subglabrous abaxially |
|
(3) |
| |
|
|
|
| 2 (1) |
Pinnae glandular abaxially, abaxially with unicellular short acicular hairs along lateral veins and intercostal areas. |
|
10 M. glandulifera |
| + |
Pinnae without glands, with grayish white multicellular spreading long acicular hairs on both surfaces. |
|
11 M. flaccida |
| |
|
|
|
| 3 (1) |
Laminae ovate-triangular |
|
(4) |
| + |
Laminae oblong or lanceolate |
|
(7) |
| |
|
|
|
| 4 (3) |
Laminae bipinnatipartite, segments entire. |
|
6 M. deltoideofrons |
| + |
Laminae pinnate-pinnatifid or 3-pinnate to 3-pinnate-pinnatifid |
|
(5) |
| |
|
|
|
| 5 (4) |
Laminae oblong, except for costae long villous adaxially, elsewhere glabrous; indusia glabrous. |
|
9 M. wuyishanica |
| + |
Laminae ovate-triangular, hairy on both surfaces; also hairy at indusia |
|
(6) |
| |
|
|
|
| 6 (5) |
Proximal pinnae sessile or with 0.5-1 mm stalk, pinnules rounded-obtuse or acute at apices, sessile. |
|
7 M. hattorii |
| + |
Proximal pinnae with 3.5-5 mm stalk, pinnules long acuminate-caudate at apices, stalk 4-7 mm. |
|
8 M. petiolulata |
| |
|
|
|
| 7 (3) |
Laminae thick, papery or thinly herbaceous; plants taller and larger, usually 75-95 cm tall or more; pinnae glabrous abaxially, or costae and costules occasionally with sparse acicular short hairs. |
|
1 M. singalanensis |
| + |
Laminae thinner, herbaceous or thinly herbaceous; plants smaller and shorter, no more than 65 cm tall; pinnae ?with short acicular hairs or glabrous abaxially |
|
(8) |
| |
|
|
|
| 8 (7) |
Pinnae glabrous abaxially, or at most with hairs along costae, costae occasionally with very sparse acicular hairs |
|
(9) |
| + |
Pinnae abaxially at least with denser short acicular hairs along costae |
|
(10) |
| |
|
|
|
| 9 (8) |
Proximal pinnae usually not shortened, also not tapering to bases; laminae adaxially with dense grayish white acicular hairs along rachises and costae; veinlets usually simple, occasionally forked. |
|
2 M. gracilescens |
| + |
Laminae with proximal 1 or 2 pairs of pinnae ?shortened, pinna bases clearly tapering; laminae adaxially with grayish white short acicular hairs along rachises and costae; veinlets on pinnules of proximal pinnae usually forked, simple distally. |
|
3 M. adscendens |
| |
|
|
|
| 10 (8) |
Pinnae arrangement sparser, proximal ones 2-4 cm from each other, bases clearly tapering; segments entire or usually with densely crenate sinuses, or pinnatifid. |
|
4 M. laxa |
| + |
Pinnae arrangement denser, proximal ones 1-2 cm from each other, bases nearly tapering, segments usually entire, at most shallowly undulate. |
|
5 M. uraiensis |
|
|
|
List of lower taxa
| Related Links (opens in a new window) |
|
Treatments in Other Floras @ www.efloras.org
Other Databases
|
|
|
|
|
|
|
