Williamsonia
Encyclopedia
Williamsonia
Williamsonia (dragonfly)
Williamsonia is a genus of small dragonflies in the family Corduliidae. They are commonly known as Boghaunters. Unlike other genera of Emerald dragonflies, they have dark eyes and non-metallic bodies.The genus consists of only two species:...

 is also a genus of corduliid
Corduliidae
The insect family Corduliidae contains the emerald dragonflies or green-eyed skimmers. These dragonflies are usually black or dark brown with areas of metallic green or yellow, and most of them have large, emerald-green eyes...

 dragonflies

Williamsonia is a fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...

 genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of Bennettitales
Bennettitales
Bennettitales is an extinct order of seed plants that first appeared in the Triassic period and became extinct toward the end of the Cretaceous...

, an extinct group of seed plants
Spermatophyte
The spermatophytes comprise those plants that produce seeds. They are a subset of the embryophytes or land plants...

. The plants looked a bit like a cycad
Cycad
Cycads are seed plants typically characterized by a stout and woody trunk with a crown of large, hard and stiff, evergreen leaves. They usually have pinnate leaves. The individual plants are either all male or all female . Cycads vary in size from having a trunk that is only a few centimeters...

, with slender trunks up to two meters tall topped with a crown of leaves.

The genus is used for fossil cones containing ovule
Ovule
Ovule means "small egg". In seed plants, the ovule is the structure that gives rise to and contains the female reproductive cells. It consists of three parts: The integument forming its outer layer, the nucellus , and the megaspore-derived female gametophyte in its center...

s, from which seeds
SEEDS
SEEDS is a voluntary organisation registered under the Societies Act of India....

would have later developed. The cones are round and include up to 50 seeds packed in among the cone scales.
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