Steven Tyler‘s latest accuser — who claims he sexually assaulted her nearly 50 years ago — filed her lawsuit against the singer in the nick of time, legally speaking … as the statute of limitations was about to run out.

Jeff Anderson, attorney for the alleged victim Jeanne Bellino, tells TMZ … he and his client recently decided to file against Tyler under New York City’s Gender-Motivated Violence Act.

Under that act, Bellino — who alleges the assault happened in New York City in 1975 when she was 17 — has a much larger window for the statute of limitations … but even so, Anderson says it was set to expire at the end of November.

As we reported, Julia Holcomb also sued Tyler at the end of last year, alleging she was sexually assaulted by the musician in 1973 when she was 16 — and also claimed he pressured her to get an abortion.

Anderson is representing both women in their respective cases.

In fact, we’re told Holcomb and Bellino plan to serve as witnesses for each other’s cases. Anderson says Bellino first came to him to say she was open to testifying for Holcomb to establish a pattern of Tyler’s alleged behavior.