Asplenium

Kessler, Michael & Smith, Alan R., 2018, Prodromus of a fern flora for Bolivia. XXIX. Aspleniaceae, Phytotaxa 344 (3), pp. 259-280 : 259-280

Key to the Bolivian species of Asplenium

1 Blades simple .................................................................................................................................................................................... 2

– Blades pinnatifid to more highly dissected ...................................................................................................................................... 7

2 Midribs and blades abaxially lacking scales .................................................................................................................................... 3

– Midribs and blades abaxially with small dark scales ....................................................................................................................... 5

3 Pinna margins crenulate to crenate .................................................................................................................................... A. pearcei

– Pinna margins entire ......................................................................................................................................................................... 4

4 Rhizome scales 0.1–0.3(0.4 mm) wide, dark brown, entire, contorted; pinnae usually>6 lateral pairs .............. A. juglandifolium

– Rhizome scales 1–2.5 mm wide, golden brown, with marginal cilia to 0.5 mm or more, not contorted; pinnae 2–6 lateral pairs .... ....................................................................................................................................................................................... A. tricholepis

5 Fertile blades 0.7–2.5(4) cm wide; veins at a narrow angle (30–45°) to the midrib ..................................................... A. angustum

– Fertile blades (3) 4–15 cm wide; veins at a wide angle (50–75°) to the midrib ................................................................................ 6

6 Blade margins usually entire, rarely serrulate; petioles fully winged (unwinged bases, if present, hidden in thick rhizome/root mass); midribs abaxially sharply keeled; fertile blades (4) 8–15 cm wide; apical buds absent ...................................... A. serratum

– Blade margins crenulate; petioles usually unwinged at the bases; midribs abaxially rounded towards blade bases; fertile blades 4–8(11) cm wide; blades sometimes with an apical bud ......................................................................................... A. stuebelianum

7 Sori marginal or nearly so, with cup- or pouch-shaped indusia (rounded at bases) .................................................... A. theciferum

– Sori not marginal, with usually abaxial elongate indusia along the veins ........................................................................................ 8

8 Blades each or most with an apical bud, often at the tip of a long, whip-like extension ................................................................. 9

– Blades lacking apical buds ............................................................................................................................................................. 19

9 Petioles and rachises dull, greenish to brown ................................................................................................................................. 10

– Petioles and rachises lustrous, dark brown, purplish, or black ....................................................................................................... 13

10 Pinnae <17 mm long, deeply incised; arid to semihumid habitats ........................................................................ A. depauperatum

– Pinnae> 20 mm long, crenate; humid forests ................................................................................................................................. 11

11 Petioles and rachises broadly winged, wings 1–2 mm wide; pinna bases equilateral to moderately inequilateral ........... A. alatum

– Petioles and rachises with narrow wings, wings <0.5 mm wide; pinna bases strongly inequilateral ............................................ 12

12 Acroscopic auricles not deeply incised ........................................................................................................................ A. macrodon

– Acroscopic auricles cut nearly or completely to the costae ..................................................................................... A. sessilifolium

13 Blades 1-pinnate to 1-pinnate-pinnatisect ...................................................................................................................................... 14

– Blades 2-pinnate or more divided ................................................................................................................................................... 17

14 Blades 1-pinnate-pinnatifid to pinnatisect ............................................................................................................................ A. hallii

– Blades 1-pinnate, the pinnae entire or dentate ................................................................................................................................ 15

15 Pinnae> 20 mm long; blades ending in a long-flagelliform apex ................................................................................ A. cirrhatum

– Pinnae <18 mm long; blades lacking a long-flagelliform apex ...................................................................................................... 16

16 Petioles black, <0.8 mm thick; pinnae 5–8 mm long; hydathodes lacking; rhizome scales bicolorous .......................... A. palmeri

– Petioles dark reddish brown to brown, 0.8–2 mm thick; pinnae 7–17 mm long; hydathodes present; rhizome scales black ............ .................................................................................................................................................................................... A. polyphyllum

17 Blades strongly narrowed proximally, with highly reduced proximal pinnae; petioles 0–3 cm long ........................... A. rutaceum

– Blades not or only slightly narrowed proximally, with fully developed proximal pinnae; petioles 5–20 cm long ........................ 18

18 Blades to 3-pinnate; ultimate segments ovate to broadly obovate with pinnate or flabellate venation; pinnule margins dentate, 1- many-lobed, or pinnules wholly 1-pinnate .............................................................................................................. A. flabellulatum

– Blades to 3-pinnate-pinnatifid; ultimate segments linear-elliptic to narrowly obovate, each with only one median vein; pinnule margins usually entire .................................................................................................................................................... A. uniseriale

19 Blades 2-pinnate or more divided; at least proximal pinnae incised fully to the costae ................................................................ 20

– Blades 1-pinnate to 1-pinnate-pinnatisect; if pinnae incised, then not fully to the costae ............................................................. 32

20 Mature leaves <6 cm long .................................................................................................................................................. A. repens

– Mature leaves (4) 6–120 cm long .................................................................................................................................................... 21

21 Proximal basiscopic pinnules larger than the opposite acroscopic ones; blades abaxially with whitish, septate hairs> 0.5 mm long; veins ending at blade margins without hydathodes ........................................................................................................ A. pumilum

– Proximal basiscopic pinnules smaller than the opposite acroscopic ones; blades abaxially lacking whitish, septate hairs; veins ending short of blade margins and forming hydathodes ...................................................................................................................... 22

22 Proximal pinnae gradually reduced ................................................................................................................................................ 23

– Proximal pinnae abruptly reduced .................................................................................................................................................. 27

23 Blades 3-pinnate; median pinnae> 20 mm long; petioles often narrowly winged ........................................................ A. cristatum

– Blades 2-pinnate; median pinnae <20(25) mm long; petioles not winged ..................................................................................... 24

24 Pinnae <8 mm long; pinnae simple and unlobed or with 2 or 3 pinnules per pinna, these entire, or 2- or 3-lobed ....................... 25

– Pinnae> 8 mm long; larger pinnules with 3–20 lobes .................................................................................................................... 26

25 Pinnae sessile, usually entire, oblong, veins simple; rachises blackish ........................................................................ A. trilobatum

– Pinnae short-stalked, usually 2- or 3(5)-lobed, lobes obovate and with the veins in pinnule lobes forked; rachises castaneous ....... ....................................................................................................................................................................................... A. triphyllum

26 Pinnae <1.5 times as long as broad; buds, if present, in axils of proximal pinnae .................................................... A. ayopayensis

– Pinnae>(1.5)2 times as long as broad; buds usually present on blade apices or in axils of distal pinnae ............... A. sessilifolium

27 Blades 15–50 cm wide; pinnules (2) 3–9 cm long; rhizome scales 4–20 mm long ........................................................................ 28

– Blades <15 cm wide; pinnules 0.5–3 cm long; rhizome scales to 5(9) mm long ........................................................................... 29

28 Pinnae trapezoidal; rhizome scales to 20 mm long; plants terrestrial ....................................................................... A. squamosum

– Pinnae linear-lanceolate; rhizome scales to 6 mm long; plants epiphytic or saxicolous ......................................... A. tunquiniense

29 Petioles and rachises with abundant long scales ...................................................................................................... A. praemorsum

– Petioles and rachises glabrous or with a few filiform scales on the petiole bases ......................................................................... 30

30 Rhizome scales linear, lustrous; ultimate segments herbaceous, obovate to subflabellulate, apically dentate; veins subdichotomously branched ............................................................................................................................................................ A. cuneatum

– Rhizome scales lanceolate to ovate, dull; ultimate segments firm-herbaceous to coriaceous, linear-lanceolate to elliptic, with entire apices; veins 1-forked to pinnately branched ................................................................................................................................. 31

31 Blades 2-pinnate (at least proximal pinnae); largest pinnules 4–7 mm wide ............................................................. A. cuspidatum

– Blades 2-pinnate-pinnatisect to 3-pinnate (at least proximal pinnae); largest pinnules 1–3(6) mm wide ...................... A. fragrans

32 Fertile leaves 1–6(9) cm long, blades 0.4–1.5 cm wide; roots filiform and giving rise to new plantlets ...................................... 33

– Fertile leaves 5–120 cm long, blades 1–10 cm wide; roots thick, not giving rise to new plantlets ............................................... 34

33 Blades pinnatisect to 1-pinnate-pinna tifid; pinnae strongly ascending, with entire margins .................................. A. escaleroense

– Blades 1-pinnate; pinnae weakly ascending, with sharply serrate margins ....................................................................... A. repens

34 Terminal pinnae similar in size and shape to lateral pinnae ........................................................................................................... 35

– Terminal pinnae gradually reduced, blade apices pinnatifid .......................................................................................................... 46

35 Pinna margins entire to undulate .................................................................................................................................................... 36

– Pinna margins crenate to sharply serrate ........................................................................................................................................ 37

36 Rhizome scales 0.1–0.3(0.7) mm wide, dark brown, ± entire, contorted ............................................................. A. juglandifolium

– Rhizome scales 1–2.5 mm wide, ciliate, golden brown, not contorted ........................................................................ A. tricholepis

37 Pinnae 1–3 pairs per blade .............................................................................................................................................................. 38

– Pinnae 6–12 pairs per blade ............................................................................................................................................................ 39

38 Leaves 20–40 cm long; pinna margins crenulate to crenate; plants epiphytic .................................................................. A. pearcei

– Leaves <18 cm long; pinnae crenulate to more deeply incised; plants terrestrial .......................................................... A. pumilum

39 Rhizomes erect; pinna margins regularly crenate or irregularly deeply incised ............................................................................ 40

– Rhizomes compact to creeping; pinna margins sharply serrate ..................................................................................................... 42

40 Venation flabellate, pinnae without a clear midvein; pinna margins irregularly and usually deeply and narrowly incised; rhizome scales with long, narrow, uniseriate apices ................................................................................................................. A. dimidiatum

– Venation pinnate, pinnae with a clear midvein; pinna margins shallowly and regularly incised; rhizome scales acuminate, without uniseriate apices .............................................................................................................................................................................. 41

41 Proximal pinnae 14–20 cm long; well-developed sori 8–22 mm long; petiole bases glabrous or with a few broad scales ................ ............................................................................................................................................................................................. A. davisii

– Proximal pinnae 4.5–15 cm long; well-developed sori 3–6 mm long; petiole bases with filiform, curled scales .................. A. feei

42 Rhizome scales 6–14 mm long ....................................................................................................................................................... 43

– Rhizome scales 0.2–5 mm long ...................................................................................................................................................... 44

43 Rhizome scales brown to blackish; rhizomes short-creeping ..................................................................................... A. incurvatum

– Rhizome scales orange to castaneous; rhizomes compact ....................................................................................... A. mosetenense

44 Rhizome scales 0.2–2 mm long ............................................................................................................................ A. micropaleatum

– Rhizome scales 2–5 mm long ......................................................................................................................................................... 45

45 Pinnae 18–36 pairs per blade; pinnae 12–23 mm wide, ± symmetric, often gradually reduced towards blade apices ....................... ........................................................................................................................................................................................ A. achalense

– Pinnae 4–16 pairs per blade; pinnae (17) 20–45 mm wide, ± asymmetric and often auriculate, usually little reduced towards blade apices ..................................................................................................................................................................................... A. serra

46 Petioles and rachises (at least proximally) lustrous, brown or castaneous to black ....................................................................... 47

– Petioles and rachises dull, green, stramineous or pale to dark brown ............................................................................................ 58

47 Pinnae> 4 cm long ........................................................................................................................................................ A. harpeodes

– Pinnae <3 cm long .......................................................................................................................................................................... 48

48 Hydathodes lacking adaxially; rachises blackish; rhizome scales with occluded cells .................................................................. 49

– Hydathodes present adaxially; rachises brown to blackish; rhizome scales with occluded or clear cells ..................................... 51

49 Blade tissue of medium thickness; terminal pinnae of fully developed leaves hastate; lateral pinnae often excavate acroscopically, lacking lobes; pinna margins crenulate ......................................................................................................................... A. lilloanum

– Blade tissue thick; terminal pinnae of fully developed leaves oblong; lateral pinnae often with a small acroscopic lobe; pinna margins essentially entire ..................................................................................................................................................................... 50

50 Pinnae 3–8 × 1.5–3 mm, spreading; blades often with proliferous apices; veins simple ................................................. A. palmeri

– Pinnae (4)10–20 × 2–5 mm, deflexed, especially at blade bases; blades lacking proliferous apices; veins once-forked ................... .......................................................................................................................................................................................... A. resiliens

51 Acroscopic pinna margins deeply (1–3 mm) incised; blades membranaceous to firm-herbaceous ............................................... 52

– Acroscopic pinna margins shallowly (<1 mm) incised; blades firm-herbaceous to coriaceous .................................................... 55

52 Basal acroscopic pinna auricles cut more than halfway to the costae; sori usually 8–12 on larger pinnae; blades firm-herbaceous. ................................................................................................................................................................................... A. sessilifolium

– Basal acroscopic pinna auricles cut less than halfway to the costae; sori usually 1–7 on larger pinnae; blades membranaceous .. 53

53 Rhizome scales with occluded cell lumina; sori 1–3 per pinna; <1500 m ................................................................... A. formosum

– Rhizome scales with clear cell lumina; sori 4–7 on larger pinnae;>(1500) 2500 m ...................................................................... 54

54 Pinna margins crenate ................................................................................................................................................. A. bolivianum

– Pinna margins sharply serrate ........................................................................................................................................ A. tabinense

55 Rhizome scales sclerotic, with occluded cells, often with narrow pale margins; rachises castaneous to black ............................ 56

– Rhizomes scales clathrate, with clear cells, concolorous; rachises brown to castaneous .............................................................. 57

56 Rachises adaxially with raised ribs conspicuously papillate with blunt, rigid papillae to 0.1 mm long; pinnae to ca. 1 cm long; sori on both basiscopic and acroscopic sides of pinnae, often 2 or 3 (or more) per pinna ................................................... A. hallbergii

– Rachises adaxially with entire, or nearly entire ribs, lacking papillae; pinnae mostly 1–2 cm long; sori usually along only basiscopic side of pinnae, often 1(2) per pinna .................................................................................................................. A. monanthes

57 Pinnae nearly round or rhomboid, 6–10 × 5–6 mm; indusia erose; blades non-proliferous ....................................... A. castaneum

– Pinnae oblong, 8–10(22) × 4–6 mm; indusia subentire; blades usually each with a subterminal bud ...................... A. polyphyllum

58 Venation flabellate, pinnae without a clear midvein, or central vein less than 50% of pinnule length; pinnae <1.4 cm long ....... 59

– Venation pinnate; pinnae 0.5–10 cm long ...................................................................................................................................... 61

59 Larger pinnae 10–14 mm long ......................................................................................................................................... A. lorentzii

– Larger pinnae 4–8 mm long ............................................................................................................................................................ 60

60 Petioles and rachises 0.2–0.7 mm thick, flexuous, greenish to stramineous; pinnae broadly and deeply dentate ............ A. gilliesii

– Petioles and rachises 0.3–1 mm thick, rigid, often reddish to grayish brown; pinnae entire to subentire or denticulate to crenulate .................................................................................................................................................................................... A. peruvianum

61 Basiscopic veins of median pinnae all simple (sometimes with a few forked veins on the proximal pinnae) .............................. 62

– Basiscopic veins of median pinnae partly or mostly forked ........................................................................................................... 71

62 Rachis wings broad (as broad or broader than rachises); petioles usually broadly winged (> 1 mm wide) .................... A. pteropus

– Rachises narrowly winged; petioles not winged or wings <0.5 mm wide ..................................................................................... 63

63 Pinna incisions ca. 0.5 mm deep .................................................................................................................................................... 64

– Pinna incisions 1 mm deep or deeper ............................................................................................................................................. 66

64 Pinnae <15 pairs per blade ......................................................................................................................................... A. pulchellum

– Pinnae>20 pairs per blade ............................................................................................................................................................. 65

65 Pinnae 2.5–3 × 0.4–0.6 cm; basal pinnae usually>50% the length of the median pinnae ................................................. A. bangii

– Pinnae 1.4–2.3 × 0.4–0.5 cm; basal pinnae usually 10–25% the length of the median pinnae ..................................... A. claussenii

66 Well developed petioles 1–2 mm thick ........................................................................................................................................... 67

– Well developed petioles 0.4–0.8 mm thick ..................................................................................................................................... 68

67 Rhizome scales dark brown to blackish; pinnae 25–50 pairs per blade ....................................................................... A. harpeodes

– Rhizome scales brown to grayish; pinnae 12–24 pairs per blade ................................................................................ A. raddianum

68 Petioles blackish;> 2500 m ............................................................................................................................................................. 69

– Petioles green or pale to dark brown; <1500 m .............................................................................................................................. 70

69 Pinna margins crenate ................................................................................................................................................. A. bolivianum

– Pinna margins deeply crenate to sharply serrate ........................................................................................................... A. tabinense

70 Pinnae acuminate, deeply serrate or incised, often halfway to costae in proximal part of each pinna; blade apices long-acuminate .......................................................................................................................................................................................... A. poloënse

– Pinnae obtuse, crenate; blade apices not elongate ...................................................................................................... A. pulchellum

71 Crenations on basiscopic pinna sides starting beyond proximal 1/4 of pinna length ..................................................................... 72

– Crenations on basiscopic pinna sides starting within proximal 1/4 of pinna length ...................................................................... 74

72 Pinnae sharply biserrate (serrations in pairs) ...................................................................................................... A. drepanophyllum

– Pinnae regularly crenate ................................................................................................................................................................. 73

73 Pinnae apically obtuse; pinnae usually 1.5–2.5 cm long ............................................................................................. A. discrepans

– Pinnae apically acuminate; pinnae usually 3–5 cm long ...................................................................................... A. inaequilaterale

74 Pinnae each with a large basal auricle ............................................................................................................................................ 75

– Pinnae lacking or with slightly developed basal auricles ............................................................................................................... 76

75 Basal pinna auricles parallel to and not overlapping the rachises; pinnae <5(7) cm long; rhizome scales entire ........... A. auritum

– Basal pinna auricles overlapping the rachises; pinnae>(4) 6 cm long; rhizome scales with long, golden hairs ....... A. salicifolium

76 Pinnae 25–50 pairs per blade ........................................................................................................................................ A. harpeodes

– Pinnae <25 pairs per blade .............................................................................................................................................................. 77

77 Indusia thin and scarious, often hyaline until mature; blades chartaceous; rhizome scales entire ................................................. 78

– Indusia (at least mature ones) firm and fleshy, opaque; blades usually fleshy; rhizome scales with long, golden hairs ............... 79

78 Pinnae acute to long-acuminate at tips, sharply biserrate,> 6 cm long ......................................................................... A. abscissum

– Pinnae obtuse at tips, evenly crenate, <5.5 cm long ..................................................................................................... A. ruizianum

79 Veins mostly 2-forked; blades each ending in a broad-based terminal segment; pinnae 4–9 cm long ..................... A. salicifolium

– Veins mostly 1-forked; blades each ending in a narrow, serrate or subcaudate apex; pinnae 3–6 cm long ................................... 80

80 Petiole scales 2–4(5) mm long; pinna apices acute or subacute ................................................................................ A. auriculatum

– Petiole scales 6–9 mm long; pinna apices often attenuate .............................................................................................. A. hastatum