Why is check_mem.pl missing?

not sure what i didn’t install - please advise -

execvpe(/usr/lib/nagios/plugins/check_mem.pl) failed: No such file or directory

on the ubuntu server to be monitored - i have the following plugin packages for 22.04 (jammy)

#/usr/lib/nagios/plugins# ls check*|wc -l
153
#/usr/lib/nagios/plugins# ls check_mem.pl
ls: cannot access ‘check_mem.pl’: No such file or directory

dpkg -l |grep plugins|grep nagios

ii monitoring-plugins 2.3.1-1ubuntu4 all Plugins for nagios compatible monitoring systems (metapackage)
ii monitoring-plugins-basic 2.3.1-1ubuntu4 amd64 Plugins for nagios compatible monitoring systems (basic)
ii monitoring-plugins-common 2.3.1-1ubuntu4 amd64 Common files for plugins for nagios compatible monitoring
ii monitoring-plugins-contrib 37.20211217ubuntu1 amd64 Plugins for nagios compatible monitoring systems
ii monitoring-plugins-standard 2.3.1-1ubuntu4 amd64 Plugins for nagios compatible monitoring systems (standard)
ii nagios-plugins-contrib 37.20211217ubuntu1 amd64 Transitional package for monitoring-plugins-contrib

check_mem.pl is neither member of ITL nor monitoring plugins project.