1	Sori (coenosori) longitudinally elongated		(2)
+	All sori orbicular or only slightly elongated		(3)
2 (1)	Fronds strongly dimorphic: sterile fronds distinctly wider, 1-7 ?1-2 cm, fertile fronds 4-16 ?0.3-1.5 cm, sori superficial.		31 P. piloselloides
+	All fronds linear, 3-9 cm ?1.5-3.5 mm, thickly fleshy, fertile fronds almost orbicular in cross section with sori deeply embedded in a groove in lamina.		32 P. angustissima
3 (1)	Rhizome scales basifixed, base cordate, rhizome tissue uniformly sclerified, without distinct sclerified strands; sori with few (ca. 10) sporangia		(4)
+	Rhizome scales pseudopeltate or peltate, rhizome tissue centrally parenchymatous, with or without sclerified strands; sori with more than 10 sporangia		(5)
4 (3)	Lamina narrowly elliptic, widest at middle, base cuneate.		1 P. stigmosa
+	Lamina obovate to oblanceolate, widest above middle, base gradually decurrent.		2 P. costata
5 (3)	Sori in a single row between midrib and margin.		3 P. linearifolia
+	Sori in several rows between midrib and margin		(6)
6 (5)	Sori in distinct pits, with central bundle of stellate paraphyses		(7)
+	Sori superficial, without central bundle of paraphyses		(10)
7 (6)	Rhizome scales broadly lanceolate, margins entire; lamina strap-shaped, up to 60 cm.		4 P. longifolia
+	Rhizome scales linear-lanceolate, margins ciliate; lamina linear-lanceolate, 1-25 cm (P. lanceolata s.l.)		(8)
8 (7)	Fronds distinctly dimorphic: sterile fronds: stipe up to 1-1.5 cm, lamina 1-6 ?0.8-2 cm; fertile fronds subsessile, lamina 8-25 ?0.5-0.8 cm.		5 P. adnascens
+	Fronds monomorphic or subdimorphic		(9)
9 (8)	Lamina subglabrous, with sparse indument, abaxial surface green.		6 P. nuda
+	Lamina with thick and persistent indument, abaxial surface gray.		7 P. lanceolata
10 (6)	Indument loose, with narrow stellate rays; fronds strongly dimorphic: sterile lamina 1.5-2 ?1.2-1.5 cm, base cordate to rounded or occasionally cuneate; fertile lamina 5-7 ?0.3-1.1 cm, base cuneate to gradually attenuate.		8 P. nummulariifolia
+	Indument appressed with hairs with wide stellate rays; fronds not or only weakly dimorphic		(11)
11 (10)	Fronds sessile or only shortly and usually indistinctly stipitate, lamina base gradually decurrent		(12)
+	Fronds distinctly stipitate, lamina base cuneate or truncate		(17)
12 (11)	Indument of sterile parts with only one type of stellate hair, these with rays always very unequal in length, lamina linear-lanceolate.		25 P. assimilis
+	Indument of sterile parts dimorphic, with curled and straight rays, latter mostly uniform in length		(13)
13 (12)	Rhizome scales pseudopeltate, 5-7.4 mm, margins entire to dentate.		26 P. mannii
+	Rhizome scales peltate, 2-5 mm, margins ciliate (P. porosa s.l.)		(14)
14 (13)	Fronds very long, narrow, lamina margins revolute over sori; sori ?scattered, sporangia sessile or subsessile.		27 P. stenophylla
+	Fronds wider or shorter, lamina margins involute, exposing sori; sori densely packed, sporangia stalks 0.5-1 ?as long as capsule (P. porosa s.l.)		(15)
15 (14)	Indument monomorphic; rhizome scales 2-3 mm.		29 P. davidii
+	Indument dimorphic; rhizome scales 3.5-7 mm		(16)
16 (15)	Fronds 0.5-1 cm wide, indument on abaxial surface appressed.		28 P. tonkinensis
+	Fronds (0.7-)1.2-3.6 cm wide, indument on abaxial surface not appressed.		30 P. porosa
17 (11)	Rhizome long creeping; fronds distant		(18)
+	Rhizome shortly creeping; fronds close together		(23)
18 (17)	Rhizome filiform, less than 1 mm in diam.; fronds slightly falcate; rays of stellate hairs of superficial layer deep brown and unequal in length, usually each with one long acicular ray directed away from lamina.		9 P. laevis
+	Rhizome 1-4 mm in diam.; fronds not falcate; rays of stellate hairs of superficial layer whitish to grayish brown or brown, appressed		(19)
19 (18)	Indumentum with an upper layer of stellate hairs with boat-shaped rays and a lower layer of hairs with woolly rays		(20)
+	Indumentum with a single layer of stellate hairs with boat-shaped rays		(21)
20 (19)	Sterile lamina 4-6 cm wide, apex caudate.		10 P. heteractis
+	Sterile lamina 2-3 cm wide, apex obtuse or rounded.		11 P. eberhardtii
21 (19)	Stellate hairs in two sizes, some much larger than others; margins of rhizome scales entire, glabrous.		12 P. ensata
+	Stellate hairs all similar in size; margins of rhizome scales ciliate		(22)
22 (21)	Lamina (1.5-)3-6(-10.5) cm, lateral veinlets indistinct, hydathodes deeply sunken.		13 P. petiolosa
+	Lamina (5-)10-20 cm; lateral veins distinct, hydathodes superficial or slightly sunken.		14 P. lingua
23 (17)	Lamina deeply hastately or pedately lobed; rhizome scales peltate		(24)
+	Lamina simple or at most with a few short lobes at base; rhizome scales pseudopeltate		(25)
24 (23)	Lamina hastately 3-5-lobed.		15 P. hastata
+	Lamina pedately 6-8-lobed.		16 P. polydactylos
25 (23)	Rhizome scales with acumen entire and glabrous.		17 P. flocculosa
+	Rhizome scales with acumen dentate or ciliate		(26)
26 (25)	Indument dense, persistent; lamina base asymmetrical to strongly asymmetrical, truncate		(27)
+	Indument thin, often not persistent; lamina base equal or slightly unequal, cuneate (P. subfurfuracea s.l.)		(28)
27 (26)	Indument with monomorphic, wide, flat rays, lamina base strongly asymmetrical		18 P. sheareri
+	Indument with dimorphic rays, straight ones narrow; lamina base slightly asymmetrical.		19 P. drakeana
28 (26)	Indument brown, persistent, thicker than below, upper layer to 2 mm in diam..		20 P. boothii
+	Indument grayish, fugacious or persistent, upper layer to 1.3 mm in diam		(29)
29 (28)	Lamina base cuneate or truncate, stipe distinct, (4-)15-31 cm		(30)
+	Lamina base very gradually narrowed, stipe indistinctly set off from lamina, less than 15 cm		(31)
30 (29)	Rhizome scales 6.5-11 ?0.7-1.3 mm.		21 P. bonii
+	Rhizome scales ca. 2 ?1 mm.		22 P. similis
31 (29)	Indument persistent, dense in mature fronds, lamina 6.5-11 cm wide; rhizome scale acumen entire, glabrous.		23 P. subfurfuracea
+	Indument fugacious, sparse or absent in mature fronds, lamina 2-5 cm wide; rhizome scale acumen ciliate.		24 P. calvata