Back
Yuguangia
Genus Yuguangia S.-G. Hao, J.-Z. Xue, Q. Wang Int. J. Pl. Sci., 168(8): 1163. Oct 2007
- Name
- Yuguangia
- Rank
- Genus
- Authors (Pub.)
- Hao S.-G.
Xue J.-Z.
Wang Q.
- Publication
- Yuguangia ordinata gen. et sp. nov., a new lycopsid from the Middle Devonian (Late Givetian) of Yunnan, China, and its phylogenetic implications [2007/10]
- Journal
- International Journal of Plant Sciences
- Volume
- 168
- Issue
- 8
- Page number
- 1163
- Year
- 2007
- Parent Taxon
- [Class] Lepidodendropsida
- Fossil Status
- stems (with sporangia)
- Type
- Yuguangia ordinata
- Diagnosis
- Small, heterosporous, ligulate lycopsid. Stems branch isotomously. Vegetative leaves persistent, consisting of pedicels and laminae. Leaf base decurrent, obovate or fusiform in shape, arranged in pseudowhorls. Distal shoots, vegetative or fertile (strobilate), isotomously branched. Bisporangiate strobili, megasporophylls occurring at proximal and microsporophylls at distal parts. Sporophylls, closely arranged in pseudowhorls, distinctly differentiated into an horizontal pedicel, an upturned lamina, and a downward ‘‘heel.’’ Megasporangia and microsporangia homomorphic, obovoid, round to elliptical in shape. Each sporophyll with one adaxial mega- or microsporangium. Each megasporangium contains four or more Trileites-type megaspores. A ligule at the distal end of the horizontal pedicel. Megaspores, spherical in shape, slightly coarse or finely rugulate in surface. Acinosporitestype microspores, rounded triangular, with curvaturae perfectae, equatorially and distally thick exine, and biform ornamentation on distal surface. Anatomy of distal axes shows an exarch primary xylem strand, a phloem zone, and a two-zoned cortex. Protoxylem tracheids with annular and helical thickenings; metaxylem tracheids with scalariform thickenings having perforate layers connecting the adjacent bars
Links by generics
Species