Nanjinganthus
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''Nanjinganthus dendrostyla'' is a fossil plant known from
Early Jurassic The Early Jurassic Epoch (geology), Epoch (in chronostratigraphy corresponding to the Lower Jurassic series (stratigraphy), Series) is the earliest of three epochs of the Jurassic Period. The Early Jurassic starts immediately after the Triassic-J ...
sediments in
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and proposed by Fu, et al. to represent a pre-Cretaceous
angiosperm Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants ...
. The material consists of numerous compression fossils which bear a resemblance to flowers. The segments bear prominent ridges, suggesting veins, and a few specimens have a branched axis perpendicular to the segments, interpreted by Fu, et al. as a branched style. Beneath the putative
perianth The perianth (perigonium, perigon or perigone in monocots) is the non-reproductive part of the flower, and structure that forms an envelope surrounding the sexual organs, consisting of the calyx (sepals) and the corolla ( petals) or tepals when ...
, Fu, et al. interpret the existence of
ovule 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'' (or remnant of the megasporangium), and the ...
s enclosed in
ovaries The ovary is an organ in the female reproductive system that produces an ovum. When released, this travels down the fallopian tube into the uterus, where it may become fertilized by a sperm. There is an ovary () found on each side of the body. T ...
, however, the preservation of this region of the structure is poor. If this fossil is an angiosperm, it would extend the first appearance of angiosperms by 50 million years. The interpretation of ''Nanjinganthus'' as an angiosperm is disputed by Coiro, Doyle & Hilton (2019), who suggest the fossils are more consistent with a
conifer Conifers are a group of cone-bearing seed plants, a subset of gymnosperms. Scientifically, they make up the division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single extant class, Pinopsida. All ext ...
, representing either fragmented pollen cones or axes which bore ovuliferous cone scales. Other authors have advanced similar criticisms, particularly disputing the interpretation of the pentamerous nature of the perianth and supporting the interpretation as a conifer cone.


References

Prehistoric angiosperm genera {{paleobotany-stub