A codex descriptus (plural codices descripti) is a copy of another (extant) manuscript. Given two extant witnesses, A and B: if recensio demonstrates that B descends from A, which means that it contains all the errors of A plus at least one more Eigenfehler (cf. Maas 1960, § 8), i.e. one of a kind that does not imply a different filiation than A (cf. Timpanaro 1981, 120), B is a codex descriptus and therefore useless for the reconstruction of the archetype. Nonetheless, such a codex can provide important information as far as the history of textual transmission is concerned. It is often difficult to irrevocably prove that a codex is entirely a descriptus.
In Latin descriptus means 'copied, transcribed' from the verb de-scrībō.
– Maas, Paul. 1960. Textkritik. 4th ed. Leipzig: Teubner. – First ed. 1927.
– Timpanaro, Sebastiano. 1981. La genesi del metodo del Lachmann. 2nd ed. Padua: Liviana. – First ed., Firenze: Le Monnier, 1963.
– ———. 2005. The Genesis of Lachmann’s Method. Translated by Glenn W. Most. Chicago: University of Chicago Press. – Translated from Timpanaro 1981.
The Latin term is used throughout.