Dictyophyllum is an extinct genus of ferns belonging to the family Dipteridaceae. It is known from the Triassic and Jurassic periods. Like most other members of the family, it consists of multiple segments of pinnate leaflets connected to an arm, of which there were two per plant. The monophyly of the genus has been questioned, with a 2018 study suggested that the genus was polyphyletic as currently used.
Species Table copied from: SpeciesLocation and agelength of basal lamina uniting adjacent pinnae
(cm)PinnaePinna
marginAngle of
2° veinShape
of lobe/
pinnulaShapeof
1° order areolesShape of 2° order areolesShape
of sorilength
(cm)number on each armShapeDictyophyllum atuelenseArgentina and Antarctica,
Lower Jurassicunknown10unknownunknownpinnatipartite75–90°straight to falcatepentagonal to heptagonal elongatedpentagonal to heptagonal isodiametricunknownDictyophyllum bremerenseAustralia and South Africa, Upper Triassicup to 3.5>147unknownpinnatifid55–70°triangularrectangular to polygonal elongatedrectangular to polygonalrounded or elongatedDictyophyllum castellanosiiArgentina,
Middle Triassic14.5–64–5linear-lanceolatelobate-serrate45–52°ovate-acuminatepolygonal elongatedpolygonal isodiametricunknownDictyophyllum davidiAustralia,
Middle Triassic1–36–205–8lanceolatedentate to pinnatifid45–65°triangularsquare, rhomboidal to heptagonal, elongated to isodiametricindistinctrounded or elongatedDictyophyllum ellenbergiiSouth Africa, Upper Triassicup to 3.5up to 205unknownlobate65°triangular to ovatepolygonal irregularpolygonal irregularcircular or elongatedDictyophyllum exileLaurasia, Upper Triassic to
Lower Jurassic0.2–1>17.5>17linear to linear-oblanceolatelobate to pinnatifid60–90°triangularpolygonalpolygonalunknownDictyophyllum exquisitumChina, Upper Triassic0.5–15.5–76–7linear- lanceolatelobate50°triangular to falcate, apiculatepolygonalpolygonalunknownDictyophyllum fuenzalidaiChile, Upper Triassicunknown35–40unknownunknowndentate80–90°triangular-falcatepentagonal- heptagonal isodiametricpolygonalunknownDictyophyllum menendezii
sp. nov.Argentina,
Middle Triassicup to 3up to
85–6oblanceolateentire to undulate70–75°–rectangular, pentagonal, hexagonal, irregular, elongatedpentagonal, rhomboidal, irregularunknownDictyophyllum nathorstiiAsia, Upper Triassic4–830–4020–25linear to lanceolatelobate60°triangular to falcate, apiculate or obtusepolygonalpolygonalcircular or variableDictyophyllum nilssoniiGreenland, Alaska, Sweden, Great Britain, China, Upper Triassic–Lower Jurassic2–5>136–9linearlobate to pinnatipartite60–90°falcatepolygonal irregularpolygonal irregularunknownDictyophyllum rugosumGreat Britain, Middle Jurassic1–2>504–5lanceolatelobate to pinnatipartite or pinnatifid80°triangular to linear-falcatepolygonal irregularpolygonal irregularroundedDictyophyllum serratumChina, Upper Triassic1–212–155–13linear to lanceolatelobate60–70°falcatepolygonalpolygonalunknownDictyophyllum tenuifoliumArgentina, Chile, Antarctica, Middle to Late Triassic, and Lower Jurassic1.56–155–7oblanceolatedentate-lobate to pinnatifid60–90°triangularpentagonal to heptagonal elongatedrhomboidal and pentagonal isodiametriccircular
References