| 1 |
Veins free |
|
(2) |
| + |
Veins ?anastomosing |
|
(9) |
| |
|
|
|
| 2 (1) |
Sterile fronds pinnate, base asymmetrical (except B. hookeriana), apex obtuse or acute |
|
(3) |
| + |
Sterile fronds bipinnatifid, base symmetrical, apex acuminate |
|
(6) |
| |
|
|
|
| 3 (2) |
Bulbil terminal on lamina. |
|
1 B. rhizophylla |
| + |
Bulbil subterminal on lamina |
|
(4) |
| |
|
|
|
| 4 (3) |
Stipe and rachis densely scaly; base of pinnae symmetrical; sporangia on all sides of costa and costules, arrangement usually moniliform. |
|
4 B. hookeriana |
| + |
Stipe and rachis subglabrous; base of pinnae asymmetrical; sporangia spreading throughout abaxial surface, arrangement fully acrostichoid |
|
(5) |
| |
|
|
|
| 5 (4) |
Sterile pinnae usually obtuse or rounded at apex; fertile pinnae 8-10 ?2-3 mm. |
|
2 B. appendiculata |
| + |
Sterile pinnae acute at apex; fertile pinnae 40-60 ?ca. 8 mm. |
|
3 B. medogensis |
| |
|
|
|
| 6 (2) |
Pinna lobes rounded at apex, 0-1 mm apart |
|
(7) |
| + |
Pinna lobes obtuse-acute at apex, 2-3 mm apart |
|
(8) |
| |
|
|
|
| 7 (6) |
Rachis with a narrow wing except for lowest part; base of lowermost pinnae symmetrical. |
|
5 B. sinensis |
| + |
Rachis without wing; base of lowermost pinnae asymmetrical. |
|
6 B. longiaurita |
| |
|
|
|
| 8 (6) |
Stipe and rachis densely scaly; pinna lobes falcate, 1-1.5 cm. |
|
7 B. tonkinensis |
| + |
Stipe and rachis subglabrous; pinna lobes triangular, 0.5-0.6 cm. |
|
8 B. fengiana |
| |
|
|
|
| 9 (1) |
Venation pattern ?irregular, veins along costae usually anastomosing and others free or rarely uniting; rachis narrowly winged or not |
|
(10) |
| + |
Venation pattern regular, veins variously anastomosing; rachis wingless |
|
(12) |
| |
|
|
|
| 10 (9) |
Pinnae pinnatifid; rachis wingless. |
|
23 B. ×ultipinna |
| + |
Pinnae subentire or crenate; rachis narrowly winged |
|
(11) |
| |
|
|
|
| 11 (10) |
Pinnae crenate; veins usually free except those along costae. |
|
24 B. ×axireticulata |
| + |
Pinnae subentire; veins anastomosing including those along costae. |
|
25 B. ×anjenensis |
| |
|
|
|
| 12 (9) |
Lateral veins with 5-8 veinlets on each side in sterile pinnae; fronds often dark brownish when dry |
|
(13) |
| + |
Lateral veins with 1-4 veinlets on each side in sterile pinnae; fronds green or purplish when dry |
|
(16) |
| |
|
|
|
| 13 (12) |
Rhizome with 4 rows of fronds; scales on base of stipe with obvious brown margin. |
|
19 B. confertifolia |
| + |
Rhizome with 2 or 3 rows of fronds; scales on base of stipe without obvious brown margin |
|
(14) |
| |
|
|
|
| 14 (13) |
Fronds 1-3 cm apart; lamina thinly herbaceous; rhizome 3-6 mm in diam.; plants terrestrial or climbing on bases of tree trunks, sometimes rheophytic or cultivated as a submerged aquatic. |
|
21 B. heteroclita |
| + |
Fronds close together; lamina thickly papery; rhizome 4-15 mm in diam.; plants terrestrial or climbing up tree trunks |
|
(15) |
| |
|
|
|
| 15 (14) |
Rhizome 10-15 mm thick, climbing to 2-3 m; sterile fronds with stipe 16-20 cm; fertile fronds 40-60 cm. |
|
20 B. scandens |
| + |
Rhizome 4-10 mm thick, short, erect; sterile fronds with stipe 32-51 cm; fertile fronds 85-112 cm. |
|
22 B. changjiangensis |
| |
|
|
|
| 16 (12) |
Venation without included free veinlets |
|
(17) |
| + |
Venation with included free veinlets |
|
(20) |
| |
|
|
|
| 17 (16) |
Fertile pinnae linear; lateral pinnae 15-24 pairs. |
|
9 B. angustipinna |
| + |
Fertile pinnae lanceolate; lateral pinnae 6-15(-17) pairs |
|
(18) |
| |
|
|
|
| 18 (17) |
Bulbils terminal; lateral pinnae ca. 15(-17) pairs; stipe sparsely scaly. |
|
11 B. tibetica |
| + |
Bulbils subterminal; lateral pinnae 6-12 pairs; stipe densely scaly |
|
(19) |
| |
|
|
|
| 19 (18) |
Sterile stipe 30-40 cm; pinnae truncate to subcordate at base. |
|
10 B. christensenii |
| + |
Sterile stipe 8-17 cm; pinnae rounded at base. |
|
12 B. hekouensis |
| |
|
|
|
| 20 (16) |
Lateral pinnae 6-15 pairs; terminal segment triangular. |
|
13 B. subcordata |
| + |
Lateral pinnae 2-7 pairs; terminal segment similar to central pinnae |
|
(21) |
| |
|
|
|
| 21 (20) |
Fertile pinnae linear, 14-45 ?as long as wide |
|
(22) |
| + |
Fertile pinnae lanceolate, 3-8 ?as long as wide |
|
(23) |
| |
|
|
|
| 22 (21) |
Fronds purplish when dry; veinlets 5-8 arising from either side of lateral veins uniting in sterile pinnae. |
|
17 B. costata |
| + |
Fronds greenish when dry; veinlets 4 arising from either side of lateral veins uniting in sterile pinnae. |
|
18 B. virens |
| |
|
|
|
| 23 (21) |
Sterile pinnae 2 or 3 pairs; sporangia arrangement acrostichoid. |
|
14 B. hainanensis |
| + |
Sterile pinnae 5-7 pairs; sporangia arrangement not acrostichoid |
|
(24) |
| |
|
|
|
| 24 (23) |
Fronds purplish or purplish brown when dry; veinlets 2 or 3 arising from lateral veins, free veinlets without thickened ends. |
|
15 B. scalpturata |
| + |
Fronds stramineous when dry; veinlets 4 or 5 arising from lateral veins, free veinlets with thickened ends. |
|
16 B. deltigera |
