Descriptor : fibrous part adjacent to the xylem

Descriptor type : categorical

Ventral cap: the ventral fibrous bundle-sheath.

Must be described on developed fvb (not on the fvb near the apex).

A genus should have a developped vcap in old stem but in young stem, this sclerifcation may not yet be developped. This character is sometimes found only in the central zone of the central cylinder. Fibrous ventral cap may consist of lignified parenchyma cells (mostly in Reniforma fvb) or fibrous cells (mostly in Vaginata fvb).

[legend of the figure]
A fibrous vascular bundle (fvb) with its different characters. AL = auricular lobe; AS = auricular sinus; dcap = fibrous dorsal cap; MS = median sinus; RP = radiating parenchyma; TP = tabular parenchyma; vasc = vascular; vcap = fibrous ventral cap.
a: Sagittata;
b: Cordata;
c: Complanata;
d: Reniforma;
e: Lunaria;
f: Vaginata.

../images/ventral_fibrous_cap.jpg

fibrous ventral cap


present (often only in the central zone)

could be present only in the central part

../images/Washingtonia_robusta.jpg

present (often only in the central part)

../images/Rhapis_humilis_copie.jpg

present (often only in the central part)

absent

../images/Hyphaene_petersiana_copie.jpg

absent


Hierarchy

identification within "subfamily" or "tribe"
 |
 |_ fibrous part adjacent to the xylem

Belongs to the groups