Morphophysiological dormancy in the basal angiosperm order Nymphaeales

Archaefructaceae, a new basal angiosperm family.

Archaefructaceae is proposed as a new basal angiosperm family of herbaceous aquatic plants. This family consists of the fossils Archaefructus liaoningensis and A. sinensis sp. nov. Complete plants from roots to fertile shoots are known. Their age is a minimum of 124.6 million years from the Yixian Formation, Liaoning, China. They are a sister clade to all angiosperms when their characters are i...

Morphophysiological dormancy in seeds of three eastern North American Sanicula species (Apiaceae subf. Saniculoideae): evolutionary implications for dormancy break

Dormancy breaking and germination requirements were determined for seeds of the eastern North American (eNA) species Sanicula canadensis, Sanicula gregaria and Sanicula trifoliata, and the data compared to those available for the European–Asian (EurA) congener Sanicula europaea. Seeds of the three eNA species had underdeveloped embryos that were physiologically dormant, i.e., morphophysiologica...

Reproductive ecology of the basal angiosperm Trithuria submersa (Hydatellaceae).

BACKGROUND AND AIMS Trithuria, the sole genus in the family Hydatellaceae, is an important group for understanding early angiosperm evolution because of its sister relationship to the ancient lineage, Nymphaeales (water lilies). Although also aquatic, Trithuria differs from water lilies in that all species are extremely small, and most have an annual life form and grow in seasonal wetlands. Ver...

Comparative Serology of the Order Nymphaeales. II. Relationships of Nymphaeaceae and Nelumbonaceae

Internal Validation of Ancestral Gene Order Reconstruction in Angiosperm Phylogeny

Whole genome doubling (WGD), a frequent occurrence during the evolution of the angiopsperms, complicates ancestral gene order reconstruction due to the multiplicity of solutions to the genome halving process. Using the genome of a related species (the outgroup) to guide the halving of a WGD descendant attenuates this problem. We investigate a battery of techniques for further improvement, inclu...