Further study of Late Devonian seed plant Cosmosperma polyloba: its reconstruction and evolutionary significance

Table 1 Comparison of morphological traits among Late Devonian seed plants

Taxon	Frond rachis arrangement	Length of primary rachis prior to bifurcation (cm)	Location of ultimate pinnae	Pinnules	Fertile rachises bearing pollen organs	Prickles
Elkinsia [5]	Equally and repeatedly bifurcated	0-13^a	on secondary and higher orders of rachises	Laminate	Isotomously and cruciately dichotomized	absent
Laceya [17, 18]	Pinnate with bifurcated primary rachis	up to 15.5	on both primary and secondary rachises	—	—	absent
Kongshania [8]	Pinnate	—	on tertiary rachises	Laminate	Isotomously dichotomized	absent
Yiduxylon [13]	Pinnate with bifurcated primary rachis	ca. 3	on tertiary rachises	Planate and highly dissected	—	absent
Telangiopsis [10]	Pinnate with bifurcated primary rachis	0^a	on secondary rachises	Planate and highly dissected	Isotomously dichotomized	on stems
Cosmosperma	Pinnate with bifurcated/trifurcated primary rachis	10.3-21.2	on tertiary rachises	Planate and highly dissected	Anisotomously dichotomized	on stems, frond rachises and cupule surfaces

ISSN: 2730-7182