Let $X$ be a smooth surface diffeomorphic to the punctured unit disk $\{(x,y)\in \mathbb{R}^2 \ | \ 0<x^2+y^2<1\}$ in the plane. It admits a lot of non equivalent complex structures, for example those induced by the diffeomorphisms with
- punctured unit disk $\mathbb{D}^*=\{z \in \mathbb{C} \ | \ 0< |z|<1\}$
- punctured unit plane $\mathbb{C}^*=\{z \in \mathbb{C} \ | \ z \neq 0 \}$
- open annuli $A(1,R)=\{ z \in \mathbb{C} \ | \ 1<|z|<R\}$
These structures are pairwise non-biholomorphic. Is this list exhaustive or am I missing some class of complex structures?
The following is (an adaptation of) theorem 10 of section 6.5 in Ahlfors "Complex Analysis".
Reducing to the 2-connected case, this gives the theorem you want.