PBIO 250 Lecture Notes

James L. Reveal

Norton-Brown Herbarium, University of Maryland

Selected Families of Pteridophytes

See a recent cladogram for the fern and fern allies

1. Lellinger, D. 1985. A field manual of the ferns and fern-allies of the United States and adjacent Canada.
2. Mickel, J. 1979. How to know the ferns and fern allies.
   

vascular plants that reproduce by spores
sporangium (-ia)
sorus (-i)
megaphylls versus microphylls
nodal leaf gap
fronds
circinate venation or "fiddle-head", image from the Australian National Botanic Garden
sporophyte and gametophyte generations
prothallus
antheridia and archegonia
heterosporous versus homosporous
megaspores versus microspores

Lycopodiophyta H.D. Scott, 1909
  Lycopodiophytina Tippo ex Reveal, 1996
   Lycopodiopsida Bartl., 1830
    Lycopodiidae Knobl., 1890
     Lycopodiales Dumort., 1829
Lycopodiaceae P. Beauv. ex Mirb., 1802: Lvs small, mostly alternate or opposite, eligulate; spores numerous and all alike in axillary or terminal sporangia; sporophylls similar to the vegetative lvs or modified; sperm biflagellate. 12 genera, 400 species, cosmopolitan. The genus Lycopodium now divided into ten or more genera; Phyloglossum (1 sp., Australia & New Zealand) is distinct. See the descriptions and photographs from the University of Hawaii, the University of Wisconsin, and from Albion College. Go to Cardillo & Samuels to review the morphology and life cycle of Lycopodiophyta and specifically the life cycle of Selaginellaceae.

    Selaginellidae Knobl., 1890
     Selaginellales Prantl, 1874
Selaginellaceae Willk., 1854: Lvs small, mostly alternate or opposite, ligulate; spores dissimilar, the megaspores usually 4, the microspores numerous, all arranged in terminal sporangia; sporophylls reduced and modified; sperm biflagellate. 1 genus, 500 species, cosmopolitan. See the descriptions and photographs from the University of Hawaii and from Albion College.

    Isoetopsida J.H. Schaffn., 1910
     Isoetidae Reveal, 1996
      Isoëtales Prantl, 1874
Isoëtaceae Rchb., 1828: Lvs elongate and grass-like, borne in a basal cluster atop a lobed corm, ligulate; spores dissimilar, the megaspores and microspores numerous, embedded at the base of the elongated megasporophyll; sperm biflagellate. 1 genera, 100 species, cosmopolitan. See Cardillo & Samuels for areview of the morphology and life cycle of Isoetes and Albion College for a description.

Equisetophyta B. Boivin, 1956
  Equisetophytina Reveal, 1996
   Equisetopsida C. Agardh (1825)
    Equisetidae Engl. & Gilg, 1924
     Equisetales Dumort., 1829
Equisetaceae Michx. ex DC., 1804: Rhizomatous perennials with upright annual or perennial stems; stems typically with a large central cavity and distinctly grooved, photosynthetic surfaces; lvs small, not photosynthetic; branches, if present, in whorls; spores numerous and each bearing 4 elaters, arranged in 5-10 elongated sporangia on a peltate sporangiophore atop the fertile stems; sperms multiflagellate. 1 genus, 15 species, cosmopolitan. See descriptions and photographs from the University of Hawaii, the University of Wisconsinand from Albion College. Go to Cardillo & Samuels to review the morphology and life cycle of Equisetum.

Psilotophyta B. Boivin ex Reveal, 1996
  Psilotophytina Tippo ex Reveal, 1996
   Psilotopsida H.D. Scott, 1909
    Psilotidae Reveal, 1996
     Psilotales Engl., 1892
Psilotaceae Eichler, 1886: Rootless, often epiphtic perennials with dichotomous, mycorrhizal rhizomes and photosynthetic branches; lvs lf-like or scale-like and mostly spirally arranged; sporangia compound (and thus a synangium), homosporous, on short lateral shoots; sperms multiflagellate. 2 genera, 4(-8) species. Tropical. See descriptions and photographs from the University of Hawaii, the University of Wisconsin, and from Albion College. Go to Cardillo & Samuels to review the morphology and life cycle of Psilotum.

Polypodiophyta Cronquist, Takht. & Zimmerm., 1966
2 classes, Polypodiopsida with 2 subclasses
19 orders and 40 families
perhaps 15,000 species
See the descriptions of the division and photographs from the University of Hawaii and the University of Wisconsin. Go to Cardillo & Samuels to review the morphology and life cycle of Polypodiophyta. See also a nice summary in German from the University of Hamburg

  Polypodiophytina Reveal, 1996

   Opioglossopsida Thomé, 1874
    Ophioglossidae Takht. ex Reveal, 1996
     Ophioglossales Newman, 1840
Ophioglossaceae (R. Br.) C. Agardh, 1822: Herbaceous perennials with a short, simple stem and mycorrhizal roots bearing 1-2 or more lvs; lvs petiolate ("stalk"), this bearing both the blade and the sporophore with the blade borne laterally; sporangia numerous, homosporous and eusporangiate, lacking an annulus; spores numerous, often 1000 or more in each sporangium. 3 genera (Botrychium, Cheiroglossa and Ophioglossum), 60 species. Cosmopolitan. See the descriptions and photographs from the University of Wisconsin and from Albion College (note the sporophores). Go to Cardillo & Samuels to review the morphology of Ophioglossales.

   Polypodiopsida Cronquist, Takht. & Zimmerm., 1966

See Cardillo & Samuels to review the morphology of Polypodiopsida and information of select families.

    Polypodiidae Cronquist, Takht. & Zimmerm., 1966

     Osmundales Bromhead, 1838
Osmundaceae Bercht. & J. Presl, 1820: Plants stout, rhizomatous, often with persistent lf-bases and fibrous roots but lacking scales; lvs erect, large, compound, the blade divided into fertile and sterile parts or sometimes all fertile or all sterile; sporangia borne in clusters but not in sori, rather large and pear-shaped on short, stout stalks, the annulus poorly developed; spores sporangiate, 256-512. 3 genera, 18 species. Cosmopolitan. See the descriptions and photographs from the University of Wisconsin and Albion College.

     Schizaeales A.B. Frank, 1877
Schizaeaceae Kaulf., 1827: Plants slender, rhizomatous, lacking scales but with septate hairs; lvs. dimorphic or divided into fertile and sterile parts; sporangia borne in 2 rows, large, ovoid or pear-shaped, the annulus poorly developed; spores sporangiate, 128-256. 5 genera, 150 species. Cosmopolitan. See the description and photographs from the University of Wisconsin.

     Parkeriales A.B. Frank, 1877
Adiantaceae Newman, 1840: Plants mostly small, rhizomatous, scaly; lvs. mostly pinnately compound; sori submarginal and usually covered by the lf-margin; sporangia with a well-developed vertical annulus; spores mostly 64. 33 genera, 350 species. Cosmopolitan. See the description and photographs from the University of Wisconsin. See Adiantum pedatum, a Maryland species.

     Marsileales J.H. Schaffn., 1910
Marsileaceae Mirb., 1802: Plants creeping and rhizomatous; lvs alternate, often floating on water or erect and emergent, in 2 rows, filiform or with 2- or 4-lflets; sporocarps firm, compressed-ovate to globose; sori 2-many; spores heterosporous, the microspores minute, 16-64, the megaspores large and solitary. 3 genera, 45 species. Cosmopolitan. See the descriptions and photographs from the University of Wisconsin and Albion College.

     Hymenophyllales A.B. Frank, 1877
Hymenophyllaceae Link, 1833: Plant filmy and delicate, rhizomatous, scaleless; lvs circinate; sori marginal and terminal on the veins with a valvate or tubular indusium; sporangia borne on an elongate stalk or sessile, the annulus oblique; spores 32-512. 10 genera, 500 species. Cosmopolitan but mainly tropical. See the description and photographs from the University of Wisconsin.

     Polypodiales Mett. ex A.B. Frank, 1877
Polypodiaceae Bercht. & J. Presl, 1820: Plants mostly small, rhizomatous, scaly; lvs simple or once pinnate, circinate; sori laminar, borne in 1-several rows, without an indusium; sporangia with a well-developed vertical annulus; spores mostly 64. 47 genera, 400 species. Cosmopolitan. See the fronds of a tiny Mexican species of Polypodium growing in a bed of moss. See the descriptions and photographs from the University of Hawaii and the University of Wisconsin.

     Cyatheales A.B. Frank, 1877
Dennstaedtiaceae Lotsy, 1909: Plants mostly large, rhizomatous, hairy but lacking scales; lvs mostly highly divided; sori marginal and protected by the enrolled lf-margin or by a flap of tissue within the margin; sporangia with a well-developed vertical annulus; spores mostly 64. 18 genera, 350 species. Cosmopolitan. See the description and photographs from the University of Wisconsin. Among the other families in Cyatheales is the Tree fern family Cyatheaceae, seen here on the edge of a subtropical forest in Guerrero, Mexico. See more images from Albion College and the University of Hamburg.
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     Aspleniales Pic. Serm. ex Reveal, 1996
Aspleniaceae Newman, 1840: Plants small to large, rhizomatous, scaly; lvs simple to highly divided; sori borne on the lower surface and exposed or covered with an indusium; sporangia with a well-developed vertical annulus; spores mostly 64. 68 genera, 3000 species. Cosmopolitan. See the description and photographs from the University of Wisconsin. Fronds of Asplenium adiantum-nigrum from Zion Canyon, Utah.

     Blechnales Pic. Serm. ex Reveal, 1993
Blechnaceae (C. Presl) Copel., 1947: Plants large, rhizomatous, scaly; lvs mostly pinnate or pinnate-pinnatifid, often dimorphic; sori borne on the lower surface in a single row covered with a flap-like indusium; sporangia with a well-developed vertical annulus; spores 64. 9 genera, 250 species. Cosmopolitan. See the description and photographs from the University of Wisconsin.

    Salviniidae Cronquist, Takht. & Zimmerm. ex Reveal, 1996
     Salviniales Britton, 1901
Salviniaceae T. Lestib., 1826: Plants floating aquatics with slender, branched stems; lvs small and crowded, alternate or whorled, simple or bilobed to dissected; sporocarps soft and thin-walled, heterosporous, the male sorus containing numerous microsporangia, the female sorus with a single, large mesaspore in the megasporangium. 2 genera, 15 species. Cosmopolitan. See the description and photographs from the University of Wisconsin. Images of Salvinia (from Hamburg) and Azolla mexicana from Utah Lake, Utah. See also a summary of the sometimes recognized segragate family Azollaceae from the University of Wisconsin and from Albion College. See also the Azolla Page and more information on the genus Azolla

Other Sites of Interest:
American Fern Society

Next Series of Lecture Notes:
Selected Families of Gymnosperms
Lecture Schedule

Last revised: 22 Jan 1999

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