Tapeinodasya Weber-van Bosse (Ceramiales, Rhodophyta)

O. De Clerck, Y.S.D.M. de Jong, and E. Coppejans
FIGURES


Tapeinodasya plate

Figs 1-2. Vegetative morphology Tapeinodasya bornetii.

Fig. 1. Habit of wet preserved specimen from Tanzania seen from underneath (HEC 11475). Scale = 1 cm.

Fig. 2. Habit of a herbarium specimen from Tanzania (HEC 12018). Scale = 1 cm.


Tapeinodasya plate

Figs 3-10. Vegetative and reproductive morphology of T. bornetii.

Fig. 3. Lateral view of a horizontally orientated axis with radially arranged axes developing from its upper surface. Scale = 500 µm.

Fig. 4. Surface view of a horizontally orientated axis with radially arranged axes developing from the axils of the pseudolateral (arrows). Scale = 500 µm.

Fig. 5. Detail of the sympodial apical organisation (arrowhead): newly formed apex). Scale = 50 µm.

Fig. 6. Detail of the apical part of the thallus with abundant tetrasporangial stichidia. Scale = 500 µm.

Fig. 7. Detail of the apical part of a stichidium showing the production of a cover cell (arrowhead) prior to the formation of the tetrasporangium (arrows). Scale = 50 µm.

Fig. 8. Recurved branch (arrowhead) developing in the middle part of the thallus. Scale = 2 mm.

Fig. 9. Detail of two anastomosing axes. Scale = 200 µm.

Fig. 10. Detail of a mature cystocarp. Scale = 250 µm.


Tapeinodasya plate

Figs 11-16. Vegetative and reproductive morphology of T. bornetii.

Fig. 11. Detail of an apical part of the thallus. Scale = 1 mm.

Fig. 12. Detail of a vegetative apex showing cellulosympodial growth and an alternating-clockwise sequence of periaxial cell formation. Scale = 10 µm

Fig. 13. Schematic representation of the branching pattern of a bilaterally organised sympodial main axis with apparently radially organised adventitious sympodial axes developing endogenously in the axils of the pseudolaterals. Scale = 250 µm.

Fig. 14. Transverse section of an older portion of an axis showing the axial cell surrounded by 4 periaxial cells and extensive cortical layers. Scale = 100 µm.

Fig. 15. Apex of a tetrasporangial stichidium showing the formation of a cover cell prior to the formation of a tetrasporangium from the second and third periaxial cell (first and fourth periaxial cells and derivatives are not illustrated). Scale = 25 µm.

Fig. 16. Cross section through a mature part of a tetrasporangial stichidium. Scale = 50 µm.
Abbreviations: ap : apex; pl : pseudolateral.


Tapeinodasya plate

Figs 17-21. Type material and original illustrations of T. bornetii and T. etheliae.

Fig. 17. Original drawing of T. bornetii by Weber-van Bosse (1923: pl. x, fig. 1). Scale = 1 cm.

Fig. 18. Original drawing of an apical part of T. bornetii by Weber-van Bosse (1923: pl. x, fig. 2). Scale = 5 mm.

Fig. 19. Lectotype of T. bornetii from the Sulu Archipelago, Philippines (L 941.155-155). Scale = 1 cm.

Fig. 20. Original drawing of a cystocarpic specimen by Weber-van Bosse (unpublished). Scale = 5 mm.

Fig. 21. Holotype of T. etheliae from the Amirante Islands, Seychelles (L. 950.45-180). Scale = 1 cm.


Tapeinodasya plate

Fig. 22. Schematic representation of the different thallus structures in the Dasyaceae.


Tapeinodasya plate

Fig. 23. Schematic representation of the relationship between the deflection of the pseudolaterals (grey bar) and the mode of periaxial formation in the Dasyaceae.