Published on January 2, 2008
A New Zealand Tree Fern: A New Zealand Tree Fern Cyathea Biodiversity and Radiation of a New Zealand Tree Fern (Cyathea):: Biodiversity and Radiation of a New Zealand Tree Fern (Cyathea): Species phylogeny for Cyathea? Pattern and timing of species diversification? Impact of habitat in driving morphological and ecological diversity of Cyathea in New Zealand? Differences in species radiation of Cyathea in New Zealand (an Island archipelago) and respective South Pacific Island habitats and evolutionary importance of habitat on biodiversity & radiation? Land Environments of New Zealand (LENZ) ALLAN WILSON CENTRE for Molecular Ecology and Evolution RSNZ: Home Develop learning modules to develop and strengthen problem solving skills of New Zealand students, relevant and interesting to students, written from a New Zealand context & perspective. Cyatheaceae: Cyatheaceae A family of 500-600 species of tree ferns. Wet, montane tropical forests around the world. Unusual: High Species Diversity, yet near uniform chromosome number, n=69[Contant(1994). Fertile diploid hybrids. At least THREE different systems of classification: 1. Tyron and Tyron(1982), 2. Holttum and Edwards(1983) 3. Lellinger*(1987). *Supported by Brownsey(2000). Cyatheaceae Classification: Cyatheaceae Classification Tryon and Tryon (1982) Alsophila Nephelea Cnemidaria Cyathea Trichipteris Sphaeropteris subgenus Sphaeropteris subgenus Sclephropteris Holttum and Edwards (1983) Cyathea subgenus Cyathea section Alsophila sub sect. Alsophila sub sect. Nephelea section Cyathea subgenus Sphaeropteris Lellinger (1987) Alsophila Cnemidaria Cyathea Sphaeropteris Data from a study of cpDNA completed by Conant(1994) shows strong support for 3 evolutionary lineages: Alsophila clade, Cyathea clade and Sphaeropteris clade, Alsophila being most basal and Cyathea and Sphaeropteris are derived sister groups. cpDNA Data are most consistent with Lellinger’s classification. Note: Taxonomically, New Zealand species are reasonably easy to identify, Classification: Classification Sori and indusial characteristics Habitat (shows geographical distribution of A. colensoi) Stipe Frond Forms Various Cyatheaceae Distributions: Various Cyatheaceae Distributions c. dealbata c. colensoi c. smithii c. cunginghamii c. medullaris Fern Life Cycle: Fern Life Cycle Mature Tree Ferns Sori on under-side of Cyathea medullaris The young gametophyte is a rarely seen plant (1-2 mm) that is a completely independent plant in the life cycle. Gametophyte Young Sporophyte emerging from gametophyte Fern Morphology (Anatomy): Fern Morphology (Anatomy) Each spore-case under the leaf(pinna) is called a sorus. Each sorus contains many sporangia. Each sporangium produce a varying number of spores. The spore-cases look different for various species of Fern, and can be used to identify them. This spore-case may be covered by a flap, called an indusium. The Tree-Fern fiddlehead gives rise to a new Frond (leaf). ‘ The young fiddlehead and it’s stalk (stipe) are often covered with hair and/or scales. Classifying Ferns(A Dichotomous Tree): Classifying Ferns (A Dichotomous Tree) To use this Key to identify Ferns, Start at the BOTTOM of the Key and follow the arrows. START HERE Does it look like a tree ? Go to Page (13) Does it Have simple, single/unlobed fronds (leaves)? Does it have fronds that are divided once? Does it have see-through fronds? Does it have fronds that are divided more than once -(NOT a tree-fern)? Go to Page (10) Go to Page (10) Go to Page (10) Go to Page (10) Morphological Classification Key: Morphological Classification Key Start at the BOTTOM Start HERE Is it a Tree Fern? YES NO Go Back to Page 5 Does it have a “Skirt” of dead fronds in this area? NO YES Does it have a “Prickly” Trunk? NO YES Cyathea medullaris Scars on trunk oval or hexagonal in shape. Are the Frond (leaf) stalks black? YES NO Cyathea dealbata Underside of leaves silver/white. Dicksonia squarrosa Slender trunk with black pegs of remaining dead fronds. (Sometimes branches) Is the “Skirt” Tidy? YES NO NO YES Are the Fronds in the “Skirt” whole? Cyathea medullaris (Young) Very uneven skirt of black frond stalks. Thick frond stalks. Cyathea smithii - Skirt made of frond stalks only. Very soft and pale fronds, horizontal like parasol. Dicksonia fibrosa Very thick and soft brown trunk. To complete a Phylogenetic Analysis of Nucleotide Sequences, go to:The Phylogenetic Tree Constructor Cyathea vs. Dicksonia: Cyathea vs. Dicksonia Cyathea dealbata .....................................................................vs. Dicksonia sqarrosa Dicksonia fibrosa. Height: Up to 10m Fronds: Up to 4m Distinguishing characters: White peg-like frond bases on trunk White stalks (stipe) and under fronds. Location: North Island, East of South Island Dry Forest or open scrub Cyathea smithii… .....................................................................vs. Height: Up to 6m Fronds: Up to 3m (HARSH) Distinguishing characters: Trunk is thick, soft and brown. Skirt of entire dead fronds. Location: North Island and South Island Forrest, semi-open scrub Height: Up to 8m Fronds: Up to 2.5m Distinguishing characters: Fronds are soft, pale, horizontal. Short skirt of dried stalks (not Frond) Location: More common in South Island at high altitudes as they like it cold and wet. Height: Up to 7m Fronds: Up to 3m Distinguishing characters: Black peg-like frond bases on trunk Black stalks, may have branches. Location: North Island and South Island, common in most Forest Cyathea the others: Cyathea the others Cyathea medullaris (Young) Cyathea medullaris (Mature) Height: Up to 20m Fronds: Up to 5m Distinguishing characters: Young ferns will often have untidy skirt of a few dead fronds. Height: Up to 1m (a creeping Fern, may have horizontal fronds along ground) Fronds: Up to 1.5m Distinguishing characters: Very slender, pale brown stalks Location: North and South Island in mountain forests. Favours damp areas/treeline. Height: Up to 20m Fronds: Up to 5m Distinguishing characters: Thick Black stalks, Oval/Hexagonal scars left where fronds are lost. Location: North Island and South Island, common in most damp valley forests. Height: Up to 20m Fronds: Up to 3m Distinguishing characters: Fronds are soft, pale, horizontal. Ragged skirt on young plants, rough stalks/dark brown and appressed. Location: Wet coasts (North and West). ? Cyathea colensoi Cyathea cunninghamii (Similar to C. medullaris) Glossary of Terms: Glossary of Terms Exit: Exit Thank you for using New Zealand Ferns, and I would like to thank: 1. Royal Society of New Zealand. 2. Allan Wilson Centre, Massey University. 3. Associate Professor Peter Lockhart, Recourses: “New Zealand Ferns and Allied Plants”, Patrick J. Brownsey and John C. Smith Dodsworth, David Bateman, pp83-89. “Native Trees of New Zealand 2”, J.T. Salmon, Reed Publishing NZ Ltd., 2003. “Which Native Tree", Andrew Crowe, Penguin Books NZ Ltd., 2001. “New Zealand Trees – Ferns”, Alina Arkins, Reed Publishing NZ Ltd., 2003. Click to Exit or click <A New Zealand Tree Fern> to return to beginning.