Sticherus Presl 1836
Creators: name: Gonzales, Jasivia
name: Kessler, Michael
Publisher: name: Zenodo
Year: 2011
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Polypodiopsida
Gleicheniales
Gleicheniaceae
Sticherus

description: Key to the Neotropical species of Sticherus and some of the interspecific hybrids
1. Blades once-pinnate ........................................................................................................................................ S. simplex
– Blades two-pinnate or more divided ............................................................................................................................ 2
2. Segments rounded, oval, or triangular, to 1 cm long ................................................................................................... 3
– Segments linear or oval, over 1 cm long .................................................................................................................. 17
3. Segments rounded, to 0.5 cm long ............................................................................................................................... 4
– Segments rounded or triangular, 0.5–1 cm long .......................................................................................................... 5
4. Abaxial segment surfaces sparsely scaly or glabrous and papillate; bud scales ciliate ............................. S. gnidioides
– Abaxial segment surfaces densely scaly, with dark orange, arachnoid scales; bud scales entire ............. S. maritimus
5. Segments glabrous on both sides ................................................................................................................................ 6
– Abaxial segment surfaces or midveins scaly ................................................................................................................ 7
6. All branches bearing segments; bud scales ciliate, with dark bases.............................................................. S. gracilis
– Only ultimate branches bearing segments; bud scales entire, with dark margins ................................... S. hypoleucus
7. Abaxial segment surfaces glabrous or sparsely scaly; midvein scales linear to filamentous ..................................... 8
– Abaxial segment surfaces densely scaly with arachnoid scales; midvein scales lanceolate or triangular to ovate .. 12
8. Aphlebiae present; bud scales to 1 mm long .............................................................................................................. 9
– Aphlebiae absent or rudimentary; bud scales over 1 mm long .................................................................................. 10
9. Rhizome lacking squamophores; bud scales bicolorous, pale orange with dark brown bases ................... S. pruinosus
– Rhizomes bearing squamophores; bud scales concolorous, orange ........................................................... S. revolutus
10. Segments triangular; midvein scales Y-shaped ...................................................................................... S. strictissimus
– Segments ovate; midvein scales lanceolate to linear ................................................................................................. 11
11. Rhizomes lacking squamophores; bud scales bicolorous, pale orange with dark brown bases .............. S. boliviensis
– Rhizomes bearing squamophores; bud scales concolorous, dull orange ..................................................... S. nervatus
12. Last branches bearing internal segments longer than broad; bud scales ovate, uniformely translucent, ciliate......... 13
– Last branches with semicircular to winglike internal segments broader than long; bud scales lanceolate, bicolorous, ciliate and/or setulose ................................................................................................................................................. 14
13. Veinlets abaxially slender, moderately raised; midvein scales lanceolate ........................................ S. brevitomentosus
– Veinlets abaxially thick, raised; midvein scales ovate to triangular ................................................................ S. ovatus
14. Abaxial segment surfaces densely scaly; veinlets thick, raised ................................................................................. 15
– Abaxial segment surfaces sparsely scaly; veinlets thin, not raised ............................................................................ 16
15. Midvein scales 0.2–0.4 × 0.1–0.2 mm, triangular to round; segments abaxially with translucent or light orange scales ................................................................................................................................................................ S. aurantiacus
– Midvein scales 0.4–2.0 × 0.05–0.20 mm, narrowly rectangular to linear; segments abaxially with reddish brown to cinnamon scales ......................................................................................................................................... S. tepuiensis
16. Aphlebiae usually absent; broad midvein scales 0.2–0.4 × 0.1 mm (linear scales are also present); bud scales bicolorous, dark-speckled ....................................................................................................................................... S. fulvus
– Aphlebiae present; broad midvein scales 0.3–0.6 × 0.3–0.4 mm (linear scales are also present); bud scales bicolorous, apically dark .............................................................................................................................................. S. fuscus
17. Bud scales entire ....................................................................................................................................................... 18
– Bud scales ciliate and/or setulose .............................................................................................................................. 22
18. Segments triangular, broadly adnate; bud scales lanceolate, with dark margins .................................... S. hypoleucus
– Segments linear to triangular, basally hastulate, shortly petiolate or adnate; bud scales ovate, translucent ............. 19
19. Petioles over 3 mm thick; all branches segmented; proximal branches with auriculate segments; distal branches with adnate segments ...................................................................................................................................... S. intermedius
– Petioles to 2 mm thick ............................................................................................................................................... 20
20. 1 st branches segmented, the segments adnate; branches diverging at angles to 130°, slightly flexuose; rhizomes rugose ..................................................................................................................................................... S. orthocladus – 1 st branches not segmented, the segments semiadnate to auriculate; branches diverging at angles over 130°, slightly to strongly flexuose; rhizomes smooth ..................................................................................................................... 21
21. Branches slightly flexuose; segment bases shortly petiolate, auriculate; segments 0.4–2.5 cm long ...... S. hastulatus
– Branches strongly flexuose; segment bases semiadnate, basiscopically auriculate; segments 2–3 cm long ................. ................................................................................................................................................................... S. retroflexus
22. Abaxial segment surfaces densely scaly throughout .................................................................................................. 23
– Abaxial segment surfaces glabrous or sparsely scaly or scaly only on midveins....................................................... 29
23. Bud scales translucent with dark parts; plants usually slender .................................................................................. 13
– Bud scales translucent, lacking dark parts; plants usually robust .............................................................................. 24
24. All scales dark orange to cinnamon; abaxial segment surfaces densely scaly; midvein scales lanceolate or stellate ... ................................................................................................................................................................................... 25
– All scales whitish to pale orange; abaxial segment surfaces sparsely to densely scaly; midvein scales rectangular to linear. ......................................................................................................................................................................... 27
25. Pinnae more than 3-forked; all branches pectinate, linear; segments oblong, to 2 cm long ............................. S. rufus
– Pinnae to 3-forked; only last branch fully pectinate, lanceolate; segments linear,> 2.5 cm long ............................. 26
26. Segments linear, to 2 mm wide; midvein scales stellate; aphlebiae narrow, trifid; fiddleheads matted with appressed scales ...................................................................................................................................................... S. chocoensis
– Segments oblong, over 3 mm wide; midvein scales lanceolate; aphlebiae pinnatifid to trifid; fiddleheads densely scaly with erect, spreading scales ............................................................................................................ S. tomentosus
27. Segments linear; bud scales narrowly lanceolate, with lattice-like cell structure, sometimes basally semi-rigid but not dark in color ....................................................................................................................................... S. ferrugineus
– Segments oblong; bud scales lanceolate, translucent, basally or on margins darker ................................................ 28
28. Pinnae to 3-forked; only last branch fully pectinate, linear; segments to 2 cm long; segments within a pinna of roughly equal size; bud scales basally darker, margins with abundant, delicate cilia; northern Andes ......................... .............................................................................................................................................................. S. arachnoideus
– Pinnae more than 3-forked; segments unequal in length, 1–3 cm long; proximal branches internally pectinate; last branch lanceolate, usually narrower than the proximal ones; bud scales translucent with dark margins bearing short, delicate cilia; Greater Antilles ................................................................................................................... S. antillensis
29. All scales ovate, entire or short-ciliate, translucent; aphlebiae lacking ..................................................................... 30
– All scales lanceolate, ciliate or setulose, translucent to bicolorous; aphlebiae present or lacking ............................ 31
30. 1 st branches arching, usually longer than the 2 nd; segments oblong, 1.5–3.0 cm × 2.0– 3.5 mm; rhizome scales lanceolate, rigid ........................................................................................................................................................ S. nudus
– 1 st branches straight, similar in length to the 2 nd; segments linear, obtuse, 1.5–2.0 cm × 2.0– 2.5 mm; rhizome scales ovate, translucent ...................................................................................................................................... S. pteridellus
31. Segments remote at least on the proximal branches; scales abaxially on branches bicolorous with dark bases, apices, or centers .................................................................................................................................................................... 32
– Segments approximate on all branches; segments linear to oblong; scales abaxially on branches translucent or centrally darkened ........................................................................................................................................................... 39
32. Branches more than 3-forked; midvein scales filamentous, translucent, whitish ............................. S. moyobambensis
– Branches less than 3(-4)-forked; midvein scales lanceolate ....................................................................................... 33
33. Aphlebiae lacking; bud scales entirely dark ...................................................................................... S. melanoblastus
– Aphlebiae present, bud scales bicolorous or entirely dark ....................................................................................... 34
34. Bud scales with dark apices........................................................................................................................................ 35
– Bud scales with dark bases or centers or entirely dark ............................................................................................. 37
35. All branches remotely pinnatisect, midvein scales stellate; sori not nested within arachnoid scales ........... S. remotus
– Only 1 st branches remotely pinnatisect; midvein scales linear and/or triangular; sori nested within arachnoid scales. .................................................................................................................................................................................... 36
36. 1 st branches longer than 2 nd; branches lacking wings between segments; abaxial segment surfaces densely scaly; Bolivia. .............................................................................................................................................................. S. jacha
– 1 st branches shorter than 2 nd; branches with wings between the segments; abaxial segment surfaces sparsely scaly; southeastern Brazil and Bolivia ........................................................................................................ S. nigropaleaceus
37. Bud scales lanceolate-subulate, with dark centers; midvein scales stellate .............................................. S. interjectus
– Bud scales lanceolate, with dark bases; midvein scales loosely stellate ................................................................... 38
38. Segments to 3.5 cm long; branches with wings between segments .................................................... S. × subremotus
– Segments> 3.0 cm long; branches lacking wings between segments .............................................. S. ×pseudobifidus
39. Ultimate branches with numerous reduced winglike internal proximal segments ................................................... 15
– Ultimate branches with internal segments lacking or gradually reduced .................................................................. 40
40. Aphlebiae lacking; last branches lacking proximal internal segments, branch outlines lanceolate, basally equally or unequally truncate ...................................................................................................................................................... 41
– Aphlebiae trifid to simple; last branches with proximal internal segments gradually reduced, branch outlines lanceolate or linear .............................................................................................................................................................. 43
41. Veinlets abaxially slightly raised; bud scales lanceolate, with numerous delicate cilia ................................ S. bifidus
– Veinlets strongly raised; bud scales rounded, entire or irregularly cilate .................................................................. 42
42. Bud scales bicolorous with dark centers and translucent margins, lanceolate, basally cordate; midvein scales imbricate, short-lanceolate to linear, translucent; rhizome scales lanceolate, dark ................................. S. brevitomentosus
– Bud scales concolorous, with lattice-like cell structure, translucent, rounded, glandular; midvein scales not imbricate, rounded; rhizome scales ovate, translucent ............................................................................................. S. ovatus
43. Bud scales completely dark or bicolorous with dark apices or scattered dark patches, margins setose and/or ciliate .. ................................................................................................................................................................................... 44
– Bud scales concolorous and translucent, or bicolorous with dark bases, margins with delicate or short, thick cilia .... ................................................................................................................................................................................... 47
44. Abaxial branch scales completely dark or bicolorous with translucent bases and dark apices; abaxial segment surfaces with dark orange scales; segments oblong, to 2 cm long........................................................................ S. fuscus
– Abaxial branch scales translucent or occasionally with dark apices; abaxial segment surface with whitish to pale orange scales; segments linear, to 3 cm long ............................................................................................................. 45
45. Aphlebiae slightly pinnatifid; Bolivia and Brazil ...................................................................................... S. decurrens
– Aphlebiae narrow, trifid; Caribbean and northern South America ........................................................................... 46
46. 1 st branches to 4 cm long; opposite pairs of branches roughly equal in length; all branches pinnatifid ....... S. cubensis
– 1 st branches over 5 cm long; opposite pairs of branches strongly unequal in length; proximal branches remotely pectinate and distally pinnatifid ............................................................................................................. S. × pseudobifidus
47. Midvein scales Y-shaped to linear or stellate ............................................................................................................. 48
– Midvein scales lanceolate to linear-lanceolate or filamentous .................................................................................. 51
48. All scales dark brown; midvein scales anchor-shaped with a long apical cilium and two lateral cilia.......................... .............................................................................................................................................................. S. longipinnatus
– All scales bicolorous, dark brown and translucent; midvein scales stellate or Y-shaped ......................................... 49
49. Veinlets slender, not raised; midvein scales stellate, proximally with some dark cilia, distally translucent ................. .................................................................................................................................................................. S. compactus
– Veinlets thick or slender, moderately to strongly raised; midvein scales Y-shaped, translucent ............................... 50
50. Plants robust, more than 2-forked; veinlets thick, strongly raised ............................................................... S. brittonii
– Plants slender, to 2-forked; veinlets slender, moderately raised ............................................................ S. strictissimus
51. Midvein scales filamentous; branches more than 3-forked ...................................................................................... 52
– Midvein glabrous or with lanceolate to linear scales; branches to 3-forked, rarely more divided............................. 54
52. Midvein scales dark orange to cinnamon; proximal branches slender, unequal in length, spreading at ca. 90°, with ca. 2 segments per cm ............................................................................................................................. S. squamosus
– Midvein scales whitish to pale orange; proximal branches thick or slender, usually equal in length, spreading at angles to 45°, with ca. 2–3 segments per cm ............................................................................................................ 53
53. Proximal branches thick, very short; segments 0.5–2.0 cm long, ca. 3 segments per cm ...................... S. lanuginosus
– Proximal branches usually slender; segments more than 3 cm long, ca. 2 segments per cm ......................... S. velatus
54. Plants usually robust; segments more than 3 cm long; bud scales thick-textured...................................................... 55
– Plants usually slender or medium-sized; segments to 3 cm long; bud scales thin-textured ..................................... 58
55. Only proximal branches abaxially scaly; bud scales whitish ................................................................... S. pallescens
– All branches abaxially scaly; bud scales whitish or bicolorous with dark brown parts ............................................. 56
56. Veinlets glabrous; sori not nested in arachnoid scales; bud scales whitish ..................................................... S. albus
– Veinlets glabrous to densely scaly; sori nested in arachnoid scales; bud scales usually bicolorous ......................... 57
57. 1 st branches longer than 2 nd; veinlets glabrous to sparsely scaly; bud scales basally dark brown with occluded cells. ............................................................................................................................................................. S. blepharolepis
– 1 st branches shorter than 2 nd; veinlets densely scaly; bud scales basally dark brown with translucent cells ................. ........................................................................................................................................................................ S. lanosus
58. Bud scales translucent with dark margins ................................................................................................................. 59
– Bud scales entirely translucent or with dark bases or centers ................................................................................... 60
59. Veinlets with simple, whitish hair-like scales; abaxial segment surfaces densely papillose; West Indies .................... ..................................................................................................................................................................... S. farinosus
– Veinlets with contorted to linear, orange, hair-like scales; abaxial segments surfaces smooth; Central and South America ................................................................................................................................................... S. rubiginosus
60. Midveins sparsely scaly to glabrous; bud scales translucent, orange ....................................................................... 61
– Midveins densely scaly; bud scales translucent or bicolorous, orange to orange with dark parts ............................ 62
61. Proximal branches not pectinate; aphlebiae broad; only last two distal branches pectinate; rhizomes bearing squamophores; Central Andes .................................................................................................................................. S. lechleri
– Proximal branches internally pectinate; aphlebiae narrow; all branches pectinate; rhizomes lacking squamophores; West Indies ............................................................................................................................................ S. jamaicensis
62. Segments ovate, revolute, to 1 cm long; scales concolorous, orange ......................................................................... 9
– Segments triangular to linear, usually over 1 cm long; scales bicolorous .................................................................. 63
63. 1 st branches slightly remotely pectinate; segment margins glabrous; veinlets glabrous .............................. S. × leonis
– 1 st branch pinnatisect; segment margins ciliate or glabrous; veinlets sparsely scaly ................................................ 64
64. Segment margins ciliate; midvein and veinlet scales whitish ...................................................................... S. furcatus
– Segment margins glabrous; midvein and veinlet scales orange ................................................................................ 65
65. Bud scales bicolorous, translucent and whitish with dark brown bases; proximal branches slightly arched, not pectinate; South America ................................................................................................................................ S. peruvianus
– Bud scales gradually bicolorous, brilliant orange with darker bases; proximal branches straight, pinnatifid to pinnatisect; Central America .................................................................................................................... S. underwoodianus
description: Published as part of Gonzales, Jasivia & Kessler, Michael, 2011, A synopsis of the Neotropical species of Sticherus (Gleicheniaceae), with descriptions of nine new species, pp. 1-54 in Phytotaxa 31 on pages 11-14, DOI: 10.11646/phytotaxa.31.1.1, http://zenodo.org/record/4894648