  In this paper we consider the category of F^\sigma of finite-dimensional
representations of a twisted loop algebra corresponding to a finite-dimensional
Lie algebra with non-trivial diagram automorphism. Although F^\sigma is not
semisimple, it can be written as a sum of indecomposable subcategories (the
blocks of the category). To describe these summands, we introduce the twisted
spectral characters for the twisted loop algebra. These are certain equivalence
classes of the spectral characters defined by Chari and Moura for an untwisted
loop algebra, which were used to provide a description of the blocks of
finite--dimensional representations of the untwisted loop algebra. Here we
adapt this decomposition to parametrize and describe the blocks of F^\sigma,
via the twisted spectral characters.
