Naga Myrmidon defenses does not match

[Yomar]

So I noticed that in the description screen (the one accessed with right click on an unit) for the Lv 3 Naga (Naga Myrmidon) it sais 40% defense in Forest and Mushrooms, but when you actually place it on a forest tile or a mushroom that's on flat he gets 50% defense.
I tried both Wesnoth 1.16 and 1.18, in both versions the mismatch between info and actual behavior is the same, while lv 1 and lvl 2 Nagas get the right defenses stated in the unit's description screen.
Why is that so ?

[lhybrideur]

It is because they have 50% on flat and 40% on forest? The best defense and the worst movement is used when a terrain has two types.
LVL2 has both 40% and LVL1 has 30% and 40%

[Yomar]

Thx.