In this paper, we study ordered ternary semigroups with an emphasis on those whose right ideals are linearly ordered by inclusion - these are called right chain ordered ternary semigroups and are a natural generalization of right chain semigroups. A prime segment of an ordered ternary semigroup \( S \) is a pair \( A \varsubsetneq B \) of neighbouring completely prime ideals of \( S \) . We obtain a classification of prime segments of right chain ordered ternary semigroups as simple (i.e., there are no further ideals between \( A \) and \( B \) ), Archimedean (i.e., for any \( b \in B \setminus A \) the ideal \( I \) generated by \( b \) satisfies \( \bigcap _{n \in \mathbb {N}}(I^n] = A \) ), exceptional (i.e., there exists a prime ideal lying properly between \( A \) and \( B \) ), or supplementary (i.e., there exists the smallest ideal among the ideals lying properly between \( A \) and \( B \) ). A key role in achieving this classification is played by two constructions of ideals in any ordered ternary semigroup, which in the case of right chain ordered ternary semigroups yield prime and completely prime ideals with certain special properties.