Table 3.

Thickness of cell walls in leaf cross-sections of representative Salsola s.l. species

Species	A. Thickness of individual cell walls towards the IS (μm)			B. Combined thickness of adjacent cell walls (μm)
	BS, KLC, KC	M1	M2	BS, KLC or KC in contact with other cells
	Towards M IS	Towards IS	Towards IS	M	BS, KLC, KC	WS
S. genistoides	0.20±0.005	0.16±0.003	0.12±0.004	0.21±0.011	0.26±0.008	0.36±0.017
S. masenderanica	0.19±0.007	0.13±0.003	0.11±0.003	0.22±0.002	0.20±0.02	0.13±0.03
S. montana	0.11±0.01	0.11±0.005	0.11±0.003	0.24±0.011	0.25±0.01	0.19±0.02
S. webbii	0.17±0.004	0.12±0.004	0.10±0.002	0.29±0.008	0.29±0.012	0.14±0.004
S. divaricata	0.31±0.01	0.20±0.01	0.07±0.002	0.29±0.013	0.24±0.02	0.73±0.02
X. richteri, C4	2.9±0.22	0.18±0.01a	0.11±0.004b	2.42±0.12	0.97±0.03	1.52±0.12

BS, bundle sheath cells surrounding veins; KC, KLC, internal layer of Kranz or Kranz-like cells; IS, intercellular air space; M, mesophyll cell; WS, water storage cell.

In each case n=15–30 measurements. Values are shown with standard errors.

^a For X. richteri, this layer represents specialized hypoderm.

^b For X. richteri, this layer could be also referred as M.

(A) Thickness of individual cell walls of BS, KLC, or KC, M1 (or hypodermal cells in Xylosalsola richteri and hypodermal-like in S. divaricata), or M2 cells when in contact with intercellular air space. (B) Combined thickness of cell walls where BS cells, KLCs, or KCs are in contact with other cells (M, WS, or an adjacent BS, KLC or KC).