Bennettitales

Reconstruction of Cycadeoidea, from here.

Belongs within: Spermatophyta.

The Bennettitales were a group of superficially cycad-like plants that lived during the Mesozoic. Bennettitales had superficially flower-like reproductive structures, but debate continues on whether they were closely related to flowering plants.

Characters (from Friis et al. 2011): Habit varying from unbranched and pachycaul to slender and more highly branched. Leaves mostly pinnate with well-developed rachis giving rise to numerous fine, parallel, occasionally dichotomous veins in lamina or lamina segments; laminae inserted onto rachis close to adaxial surface. Stomata paracytic, cutinised. Reproductive structures flower-like, unisexual or bisexual, consisting of bracts surrounding ovulate and/or pollen-producing organs, pollen-producing organs attached below ovules when bisexual. Ovule-producing structures with ovules and interseminal scales borne laterally on swollen axis (receptacle); ovules orthotropous, generally small, usually radially symmetrical, envelope present surrounding integument; integument fused to nucellus for most of its length, extended at apex into long micropylar tube.

<==Bennettitales
    |--Weltrichia Z02
    |--Sturiella Z02
    |--Zamites GT02
    |--Vardekloeftia sulcata [incl. V. conica] FC07
    |--Cycadeoidella japonica FC07
    |--Bennettites crossospermus FC07
    |--Williamsonia FC07
    |    |--W. bockii FC07
    |    |--W. himas FC07
    |    |--W. scotica FC07
    |    `--W. sewardiana FC07
    `--Cycadeoidea FC07
         |--C. albiana [=Bennettites albianus] FC07
         |--C. dacotensis FC07
         |--C. dartoni FC07
         |--C. gibsoniana FC07
         |--C. maccafferyi FC07
         `--C. morierei [=Williamsonia morierei, Bennettites morierei] FC07

*Type species of generic name indicated

REFERENCES

Friis, E. M., P. R. Crane & K. R. Pedersen. 2011. Early Flowers and Angiosperm Evolution. Cambridge University Press.

[FC07] Friis, E. M., P. R. Crane, K. R. Pedersen, S. Bengtson, P. C. J. Donoghue, G. W. Grimm & M. Stampanoni. 2007. Phase-contrast X-ray microtomography links Cretaceous seed with Gnetales and Bennettitales. Nature 450: 549-552.

[GT02] Gomez, B., F. Thévenard, M. Fantin & L. Guisberti. 2002. Late Cretaceous plants from the Bonarelli Level of the Venetian Alps, northeastern Italy. Cretaceous Research 23: 671-685.

[Z02] Zherikhin, V. V. 2002. Ecological history of the terrestrial insects. In History of Insects (A. P. Rasnitsyn & D. L. J. Quicke, eds) pp. 331-388. Kluwer Academic Publishers: Dordrecht.