Ptisana


Ptisana is a genus in the eusporangiate fern family Marattiaceae, comprising species historically treated in the genus Marattia. The establishment of this genus follows the 2008 work by Andrew G. Murdock, which supported recognition of this group on the basis of genetic analysis and morphology. Ptisana can be distinguished from Marattia by the presence of distinct sutures at the point of leaflet attachment, deeply cut synangia, and the absence of labiate sporangial apertures. The name Ptisana is derived from the Latin word for pearl barley, an allusion to the shape of the synangia.
Ptisana has a palaeotropical distribution, with the westernmost extreme of the range in Ascension Island and extending eastward through tropical Africa, Asia, and Oceania. Ferns in this genus are generally quite large, with fronds often reaching 2–3 meters in length; the one known exception to this is Ptisana rolandi-principis, a critically endangered dwarf species endemic to the Plateau de Dogny in New Caledonia. The basal chromosome number for Ptisana is 2n=78, whereas the one count for Marattia in the strict sense is 2n=80. The type species for the genus is Ptisana salicina, the type specimen of which was collected on Norfolk Island.

Species

, World Ferns accepts the following 36 species:
  • Ptisana africana Christenh. – East Africa
  • Ptisana ambulans Murdock & C.W.Chen – Solomon Islands
  • Ptisana attenutata Murdock – New Caledonia
  • Ptisana boivinii Senterre & Rouhan – Madagascar
  • Ptisana boninensis Yonek. – Bonin Islands
  • Ptisana costulisora Murdock – New Guinea and nearby islands
  • Ptisana decipiens Murdock & C.W.Chen – Solomon Islands
  • Ptisana fraxinea Murdock – Africa to India, including Indian Ocean islands
  • Ptisana grandifolia Murdock – New Guinea
  • Ptisana howeana Murdock – Lord Howe Island
  • Ptisana kingii Christenh. – New Guinea
  • Ptisana koordersii Christenh. – Sulawesi
  • Ptisana laboudalloniana Senterre & I.Fabre – Seychelles
  • Ptisana melanesica Murdock – New Guinea and nearby islands
  • Ptisana mertensiana Murdock – Micronesia
  • Ptisana novoguineensis Murdock – New Guinea
  • Ptisana obesa Murdock – New Guinea
  • Ptisana odontosora Senterre & Rouhan – Guinea
  • Ptisana oreades Murdock – northern Australia
  • Ptisana papuana Murdock & C.W.Chen – Solomon Islands
  • Ptisana paleolata – Sumatra
  • Ptisana pellucida Murdock – Malaysia, Philippines
  • Ptisana platybasis Murdock – New Guinea
  • Ptisana purpurascens Murdock – Ascension Island
  • Ptisana rigida Murdock – New Guinea, Sulawesi
  • Ptisana robusta Senterre & I.Fabre – São Tomé
  • Ptisana rolandi-principis Christenh. – New Caledonia
  • Ptisana salicifolia Senterre & Rouhan – South Africa, Zimbabwe, Malawi and Mozambique
  • Ptisana salicina Murdock – king fern; South Pacific islands, including New Guinea
  • Ptisana sambucina Murdock – Malesia and Vietnam
  • Ptisana senterreana Christenh. – Cameroon, Gabon, Equatorial Guinea
  • Ptisana smithii Murdock – Vanuatu, Fiji, Samoa, Tonga
  • Ptisana soluta Murdock & Perrie – New Caledonia
  • Ptisana squamosa Murdock – New Guinea
  • Ptisana sylvatica Murdock – Malesia
  • Ptisana ternatea Murdock – Moluccas, New Guinea, the Philippines

    Phylogeny

Phylogeny of ''Ptisana''