Histiopteris

General description: 

Histiopteris is from the Greek word histion meaning a web and pteris meaning a fern. Histiopteris is a terrestrial plant found in moist areas and can form large colonies if conditions are ideal. Histiopteris is known in reference to its unique netted vein pattern, it consists of a single large rhizome which its length is 0.4 m and leaf length up to 0.5 m.The fronds of Histiopteris are soft and  can grow up  to two meters long on opposite sides of the stem, with deeply lobed segments.

Figure1.1:Histiopteris plant (David, 1999).

Figure 1.2: Histiopteris leaves (David, 1999).

Conservation status: 

Conservation Code: Not Threatened

Threats: 

Not evaluated according to the International Union of Conservation of Nature.

Diagnostic description: 

Histiopteris has wide long-creeping rhizome lying horizontally along the soil and the rhizomes have scales indumentum attached.  Histiopteris consist of large fronds well-spaced 2–4 pinnate meaning on either side of the steam; the leaves have no hairs and are covered with a bloom giving a bluish lustre. Anastomosing veins which means a cross connection of veins in a leaf freely unite to a marginal commissural vein in Histiopteris. In Histiopteris a pair of pinnae is present at the rhachis which is the main axis above the lowermost primary pinna. Sorus which is a cluster of sporangia known as Sori is present in a continuous line at the margins on the connecting vein. This occurs within the vein in the paraphyses protected by reflexed membranes which is a thin membrane covering the lamina margins. Lamina margins are the expanded part of a leaf or labellum near the edge of the leaf.  In Histiopteris there are a monolete of spores bilateral which have a single straight scar of spores covered with thin tubercles.

Taxon biology: 

Histiopteris  one of the most attractive ferns, but if the conditions are right it can spread and exclude other plants from the environment.

Histiopteris is sensative to frost.

Evolution: 

There was no information on the genus itself, but there was little information found on the family.

Cytologically, the Dennstaedtiaceae and Lindsaeaceae are extremely variable and include a range of base numbers between x = 26 and x = 48. Lovis (1977) suggested that evolution in the two groups may be the result of a long series of aneuploid reductions, perhaps from a source in the Cyatheaceae.

Phylogeny: 

Kingdom: Plantae
              

                        Phylum: Charophyta
 

                                            ClassEquisetopsida
 

                                                         Subclass: Polypodiidae
 

                                                                            Order: Polypodiales
 

                                                                                         Family: Dennstaedtiaceae
 

                                                                                                            Genus: Histiopteris
 

Distribution: 

Histiopteris is located extending from  southern Chile, South Africa, Australia, New Zealand and the Subantarctic islands. In Australia, Histiopteris is common along the south-eastern and eastern coasts of South Australia and Tasmania. Histiopteris is also located in the tropics in Queensland and as far north as the  Kakadu area of the Northern Territory. There is a single record of Histiopteris from the Kimberley in Western Australia. The largest population in Western Australia is in the southern temperate regions of south west Australia. 

The distribution of Histiopteris in Australia can be visually identified in more detail on a map following this link: http://bie.ala.org.au/species/urn:lsid:biodiversity.org.au:apni.taxon:31...


Figure 1.3: Map Indicating the distribution of Histiopteris represented in colour.

Habitat: 

Histiopteris preferred habitat conditions consist of  partially shaded moist areas varying from subtropical to tropical locations. In Western Australia Histiopteris has been located in the south west on a steep slope of a  granite boulder 1.5 m in the area of the Denmark River. The habitat of the Histiopteris in the south west of Australia included mainly  substantial areas of woodland and forest.

Uses: 

According to my research conducted at this point in time there is no relevant use of the fern Histiopteris except for esthetical purposes in gardens. 

Taxonomic name: 
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith