Bennettitales †

Ecology & Form

Stems

• Short tree

• Woody stems that are heavily armored with persistent leaf bases

• Very cycad-like vegetatively; example of convergent evolution

Cycadeoids 

• • Stout trunks with bisporangiate strobili

Williamsonia † and Williamsoniella † 

• Slender, branching trunks with either bisporangiate or monosporangiate strobili

Leaves

• Pinnate and cycad-like leaves with syndetocheilic stomata (Form genus is Nilssonia †)

• The form genera Anomozamites † and Pterophyllum † also represent bennettitalean foliage.

• Oleanane present (similar to angiosperms)

Roots

• Unknown

Reproductive Structures

• Bisexual seed-cones that are flower-like 

• Outermost sterile bracts similar to sepal-like structures 

• Possible colorful petal-like structures

  • May have attracted and been pollinated by early invertebrates

• Microsporophylls are pinnate fronds with pollen sacs 

• Ovulate structure

  • Ovules alternate with scales on the ovulate receptacle

  • Reminiscent of angiosperm carpel (may be too derived to be ancestral to angiosperms)

• Ovules

  • Reduced gametophyte

  • Rapid fertilization and embryogenesis after pollination