Nanjinganthus

Nanjinganthus; Temporal range: Early Jurassic, 174 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Spermatophytes
Clade:	Angiosperms (?)
Genus:	†Nanjinganthus; Fu et al., 2018
Species:	†N. dendrostyla
Binomial name
	†Nanjinganthus dendrostyla; Fu et al., 2018

Nanjinganthus dendrostyla is a fossil plant known from Early Jurassic sediments in China and proposed by Fu, et al. to represent a pre-Cretaceous angiosperm. 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, Fu, et al. interpret the existence of ovules enclosed in ovaries, 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.[1][2]

The interpretation of Nanjinganthus as an angiosperm is disputed by Coiro, Doyle & Hilton (2019), who suggest the fossils are more consistent with a conifer, representing either fragmented pollen cones or axes which bore ovuliferous cone scales.[3] Other authors have advanced similar criticisms, particulartly disputing the interpretation of the pentamerous nature of the perianth and supporting the interpretation as a conifer cone. [4]

References

Fu, Qiang; Diez, Jose Bienvenido; Pole, Mike; Ávila, Manuel García; Liu, Zhong-Jian; Chu, Hang; Hou, Yemao; Yin, Pengfei; Zhang, Guo-Qiang (2018-12-18). "An unexpected noncarpellate epigynous flower from the Jurassic of China". eLife. Retrieved 2018-12-24.
"Fossils suggest flowers originated 50 million years earlier than thought". ScienceDaily. Retrieved 2018-12-24.
Mario Coiro; James A. Doyle; Jason Hilton (2019). "How deep is the conflict between molecular and fossil evidence on the age of angiosperms?". New Phytologist. in press (1): 83–99. doi:10.1111/nph.15708. PMID 30681148.
Sokoloff, Dmitry D.; Remizowa, Margarita V.; El, Elena S.; Rudall, Paula J.; Bateman, Richard M. (2019). "Supposed Jurassic angiosperms lack pentamery, an important angiosperm-specific feature". New Phytologist. 0. doi:10.1111/nph.15974. ISSN 1469-8137. PMID 31418869.

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[1] Fu, Qiang; Diez, Jose Bienvenido; Pole, Mike; Ávila, Manuel García; Liu, Zhong-Jian; Chu, Hang; Hou, Yemao; Yin, Pengfei; Zhang, Guo-Qiang (2018-12-18). "An unexpected noncarpellate epigynous flower from the Jurassic of China". eLife. Retrieved 2018-12-24.

[2] "Fossils suggest flowers originated 50 million years earlier than thought". ScienceDaily. Retrieved 2018-12-24.

[3] Mario Coiro; James A. Doyle; Jason Hilton (2019). "How deep is the conflict between molecular and fossil evidence on the age of angiosperms?". New Phytologist. in press (1): 83–99. doi:10.1111/nph.15708. PMID 30681148.

[4] Sokoloff, Dmitry D.; Remizowa, Margarita V.; El, Elena S.; Rudall, Paula J.; Bateman, Richard M. (2019). "Supposed Jurassic angiosperms lack pentamery, an important angiosperm-specific feature". New Phytologist. 0. doi:10.1111/nph.15974. ISSN 1469-8137. PMID 31418869.