Hamatophyton is a genus of the extinct Sphenophyllales horsetails. Unique to this genus among other Sphenophyllales is its lack of secondary xylem around the tips of the primary xylem arms.[2] One of its species has also been placed in the genus Sphenophyllostachys, which is regarded as a synonym of Bowmanites by the Interim Register of Marine and Nonmarine Genera.[3]
| Hamatophyton Temporal range:
| |
|---|---|
Scientific classification 
| |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Division: | Polypodiophyta |
| Class: | Polypodiopsida |
| Subclass: | Equisetidae |
| Order: | †Sphenophyllales |
| Genus: | †Hamatophyton L.-H. Deng, X.-X. Li, Z.-Y. Zhou, R. Xu, J.-N. Zhu, nom. inval.[1] |
| Species | |
Taxonomy edit
The taxonomic status of the genus and its possible species is confused. As of February 2024[update], the International Fossil Plant Names Index regards Hamatophyton as an invalid name since its publication in 1974 because the species name on which the genus was based, Hamatophyton verticillatum, is invalid as no type was designated.[1] In 1991, Hamatophyton verticillatum was transferred to the genus Sphenophyllostachys as Sphenophyllostachys verticillata, but since the basionym was invalid, this name is also invalid.[4]
Both species that have been placed in Hamatophyton are also treated as synonymous with Rotafolia songziensis.[5]
Species edit
- †Hamatophyton verticillatum L.-H. Deng, X.-X. Li, Z.-Y. Zhou, R. Xu, J.-N. Zhu, nom. inval., syns Sphenophyllostachys verticillata,[6] Rotafolia songziensis[5]
- †Hamatophyton yiduense (G.-X. Chen) S.-N. Feng, nom. inval., syns Sphenophyllum yiduense,[7] Rotafolia songziensis[5]
References edit
- ^ a b "Hamatophyton". International Fossil Plant Names Index. Retrieved 2024-02-24.
- ^ Taylor, T.N.; Taylor, E.L. & Krings, M. (2009). Paleobotany, The Biology and Evolution of Fossil Plants (2nd ed.). Amsterdam; Boston: Academic Press. ISBN 978-0-12-373972-8.
- ^ "Bowmanites". Interim Register of Marine and Nonmarine Genera. Retrieved 2024-02-24.
- ^ "Sphenophyllostachys verticillata". International Fossil Plant Names Index. Retrieved 2024-02-24.
- ^ a b c Wang, De-Ming; Hao, Shou-Gang & Wang, Qi (2005). "Rotafolia songziensis gen. et comb. nov., a sphenopsid from the Late Devonian of Hubei, China". Botanical Journal of the Linnean Society. 148 (1): 21–37. doi:10.1111/j.1095-8339.2005.00387.x. S2CID 82456089.
- ^ "Hamatophyton verticillata". International Fossil Plant Names Index. Retrieved 2024-02-24.
- ^ "Hamatophyton yiduense". International Fossil Plant Names Index. Retrieved 2024-02-24.
 | This fern-related article is a stub. You can help Wikipedia by expanding it. |
 | This article related to a Devonian plant is a stub. You can help Wikipedia by expanding it. |
 | This article related to a Carboniferous plant is a stub. You can help Wikipedia by expanding it. |