Yiduxylon

Name

Yiduxylon

Rank

Genus

Authors (Pub.)

Wang D.-M. Liu L.  

Publication

A new Late Devonian genus with seed plant affinities [2015/2]

Journal

BMC Evolutionary Biology

Volume

15

Issue

28

Page number

8

Year

2015

Parent Taxon

[Class] Moresnetiopsida

Fossil Status

stems

Type

Yiduxylon trilobum

Diagnosis

Stems with fronds borne helically in a 1/3 phyllotaxy. Frond rachises bifurcate proximally. Two orders of pinnae with alternately arranged secondary pinna rachises bearing alternate pinnules which are planate and highly dissected. Stems protostelic with small three-ribbed primary xylem, broad secondary xylem, and narrow cortex. Primary xylem mesarch with each rib possessing a single peripheral protoxylem strand. Secondary xylem intermediate between manoxylic and pycnoxylic types. Multiseriate bordered pits on tangential and radial walls of secondary xylem tracheids. Rays usually biseriate and very high. Cortex consisting of an outer sparganum zone and an inner parenchymatous ground tissue. Two leaf traces successively derived tangentially from tip of each primary xylem rib and once divided to produce four traces in stem cortex. Leaf traces possessing mesarch primary xylem. Petiole base containing vascular supply of four bundles in two C-shaped groups (each group with concave surface facing stem center and protoxylem strands on abaxial surface), peripheral and parallel bands of sclerenchyma cells, and ground tissue of parenchyma cells.