Blechnaceae

Gasper, André Luís De, Dittrich, Viníciusantonio De Oliveira, Smith, Alan R. & Salino, Alexandre, 2016, A classification for Blechnaceae (Polypodiales: Polypodiopsida): New genera, resurrected names, and combinations, Phytotaxa 275 (3), pp. 191-227 : 196-197

Key to the Blechnaceae taxa

1. Plants truly aquatic (submerged in water) ......................................................................................................... Oceaniopteris francii

–. Plants terrestrial, epipetric, scandent or occasionally epiphytic, sometimes growing in swamps .....................................................2

2. Sori exindusiate or with pseudoindusia (recurved pinna margins).....................................................................................................3

–. Sori indusiate......................................................................................................................................................................................4

3. Rhizomes erect, stout, trunk-like or forming stout caudices to about 1 m tall; fronds subdimorphic ...................... Brainea insignis

–. Rhizomes long-creeping, climbing; fronds dimorphic................................................................................................... Stenochlaena

4. Sterile blades with at least partially anastomosing veins ...................................................................................................................5

–. Sterile blades with free veins............................................................................................................................................................10

5. Pinnae articulate to rachises .................................................................................................................................. Anchistea virginica

–. Pinnae not articulate to rachises .........................................................................................................................................................6

6. Blades pinnatisect, abruptly or subabruptly reduced proximally .................................................................. Blechnidium melanopus

–. Blades simple, pinnate (at least proximally), or bipinnate .................................................................................................................7

7. Pinna margins finely denticulate .......................................................................................................................................... Blechnum

–. Pinna margins entire, serrate, serrulate, crenate, or spinulose............................................................................................................8

8. Areoles arranged in a single order (row) on each side of costae, all areoles of similar size and shape................................... Doodia

–. Areoles clearly arranged in first and second order rows on each side of costae, the first order fertile, the second order sterile and of different shape and size ......................................................................................................................................................................9

9. Fronds strongly dimorphic, the fertile ones with greatly contracted pinnae ........................................................ Lorinseria areolata

–. Fronds monomorphic........................................................................................................................................................ Woodwardia

10 Blades climbing via twining rachises .............................................................................................................................. Salpichlaena

–. Blades not climbing via twining rachises, if climbing via rhizomes................................................................................................11

11. Rhizomes stoloniferous ....................................................................................................................................................................12

–. Rhizomes not-stoloniferous..............................................................................................................................................................15

12. Fronds monomorphic to subdimorphic ................................................................................................................................ Blechnum

–. Fronds dimorphic..............................................................................................................................................................................13

13. Rhizome apices and stipe bases bearing linear-lanceolate scales; blades discolorous; rachises deeply grooved.................. Lomaria

–. Rhizomes bearing by lanceolate or ovate scales; blades concolorous; rachises shallowly grooved................................................14

14. Pinnae each with an obtuse apex; rachises mostly glabrous or with diminute hairs; fertile fronds taller than sterile ones................. .................................................................................................................................................................................... Austroblechnum

–. Pinnae each with an acute apex; rachises pilose, with persistent, fine, uniseriate hairs; fertile and sterile fronds similar in size....... ............................................................................................................................................................................. Cranfillia vulcanica

15. Rhizomes long-creeping, climbing...................................................................................................................................................16

–. Rhizomes erect, short- or long-creeping, sometimes forming erect caudices, but not climbing .....................................................17

16. Rhizomes clothed with long-lanceolate, denticulate or entire scales; blades deeply pinnatisect or pinnate in the proximal half, with vestigial or auricles pinnae proximally; sterile pinna margins entire............................................................................... Lomaridium

–. Rhizomes clothed with linear-lanceolate, squarrose scales; blades pinnate, with sterile terrestrial blades smaller than epiphytic ones (di- to trimorphic), 2–6 pairs somewhat reduced proximally; sterile pinna margins serrulate .................................. Icarus filiformis

17. Pinnae articulate to rachises .............................................................................................................................................................18

–. Pinnae not articulate to rachises .......................................................................................................................................................19

18. Pinna margins serrate; rhizomes long-creeping; fronds monomorphic to subdimorphic........................................ Telmatoblechnum

–. Pinna margins entire to crenate; rhizomes erect; fronds dimorphic ............................................................................. Parablechnum

19. Blades pinnate-pinnatifid or bipinnatifid..........................................................................................................................................20

–. Blades simple, pinnatifid, or 1-pinnate.............................................................................................................................................21

20. Rhizomes erect, subarborescent, stout; fronds monomorphic................................................................................................ Sadleria

–. Rhizomes long-creeping to short-creeping, if caudices erect then slender; dimorphic or slightly dimorphic............ Diploblechnum

21. Veins immersed in leaf tissue, almost invisible (except in Lomariocycas aurata ) ..........................................................................22

–. Veins readily visible .........................................................................................................................................................................23

22. Rhizomes erect, stout, trunk-like, densely clothed with bicolorous, acicular, curved, basally thickened scales .......... Lomariocycas

–. Rhizomes short, ascending or suberect, bearing at apices a tuft of orange-brown, glabrous, lanceolate scales .................................. .................................................................................................................................................................. Cleistoblechnum eburneum

23. Proximal pinnae clearly stalked; blade apices conform to subconform...........................................................................................24

–. Proximal pinnae adnate, eventually subpetiolulate; blade apices pinnatifid....................................................................................25

24. Blades truncate, without vestigial auriculate pinnae proximally; pinnae falcate, oblong-linear, lanceolate; indusia subentire to lacerate or erose............................................................................................................................................................ Parablechnum

–. Blades truncate with many vestigial auricles proximal to large pinnae; pinnae linear to narrowly elliptic, often with a basiscopic lobe; indusia entire at maturity ......................................................................................................................................... Blechnopsis

25. Fronds monomorphic................................................................................................................................... Neoblechnum brasiliense

–. Fronds dimorphic or subdimorphic ..................................................................................................................................................26

26. Rhizome scales linear-lanceolate or acicular, or scales sometimes pectinate and broadened only at the very base, otherwise acicular for nearly their entire length .............................................................................................................................................................27

–. Rhizome scales lanceolate, ovate, sometimes acuminate.................................................................................................................29

27. Blades discolorous; rachises deeply grooved......................................................................................................................... Lomaria

–. Blades concolorous; rachises shallowly grooved.............................................................................................................................28

28. Rhizomes short-creeping to erect, sometimes trunk-like, bearing black, entire scales; blades slightly reduced proximally; pinna margins entire to serrate or dentate................................................................................................................................ Oceaniopteris

–. Rhizomes short-creeping or elongate, bearing brown to dark brown, entire or sparingly toothed scales; blades very gradually reduced proximally with proximal pinnae auriculate; pinnae margins entire ................................................................... Struthiopteris

29. Stipes, rachises, costae, and veins pilose.............................................................................................................................. Cranfillia

–. Stipes, rachises, costae, and veins glabrous .....................................................................................................................................30

30. Rhizomes erect, forming narrow trunks ...........................................................................................................................................31

–. Rhizomes erect, but not forming narrow trunks...............................................................................................................................32

31. Veins each ending in a clavate hydathode .................................................................................................................. Austroblechnum

–. Veins not ending in hydathodes, all running to the pinna margins................................................................................... Lomaridium

32. Pinnae petiolulate; blade apices radicant.............................................................................................................................. Cranfillia

–. Pinnae sessile or adnate; blade apices not radicant ..........................................................................................................................33

33. Blades truncate proximally, without auriculate pinnae below the longest pinnae................................................................ Cranfillia

–. Blades gradually or abruptly reduced to auricles proximally, or blades simple...............................................................................34

34. Blades simple, pinnatifid, or pinnate, if pinnate, then pinnae oblong to suborbicular and margins crenate to serrate........................ .................................................................................................................................................................................... Austroblechnum

–. Blades pinnate; pinnae oblong-linear to linear-falcate; margins entire.......................................................................... Struthiopteris