COBOL is 57 years old, has billions of lines running, and new code is constantly developed. Should be on list.
LISP is widespread in education as Scheme, has lasting commercial deployments/companies with LispWorks and Franz Allegro, and new community with Clojure. However, one might treat them as separate languages given LISP 1.0 is very different from Common LISP which isn't Scheme or Clojure. So, it's up for debate but Scheme at 47 years old is probably justifiable due to academics. Racket is practical version with strong community. Chicken Scheme had one last I checked, too.
PL/1 (53 years old) is dead outside of legacy systems including mainframes and eComStation (OS/2). Yet, might be worth adding given that it has new code added to extend old systems like COBOL does. New compilers updates happen as well like below. Hard to say it's dead if it's still running companies, getting extended, and getting tooling updates. Just not popular.
http://www.iron-spring.com/readme_linux.html
Also, Burrough's MCP is still around under Unisys banner. It was first OS written in high-level, safer language: Burrough's ALGOL (56 years old). Became ESPOL (48yrs old) and NEWP (???). Unisys has a 2015 dated doc on NEWP. I think that means they converted most or all of the OS to it.
BASIC (52 yr old) was a language designed for beginners. Since it looked like pseudo-code, it was ridiculously easy to read and write. I got started on VB incidentally. Many spinoffs with wide deployments of commercial BASIC's for business, gaming, and education show it's far from dead. Not to mention 4GL's that were often BASIC-like. Could actually be one of the most widely, built-on languages ever made.
https://en.wikipedia.org/wiki/List_of_BASIC_dialects
So, there's more for your list.
EDIT to add BASIC in there.