I lose females faster than males. I think spawning must take years off them. For gobies, the females lasted 3 years in captivity (WC, so who knows how old), while I've got the widowed males still. Same with L. multifaciatus: females die within 2 years, but have 4-5 year old males. I have started losing some WC cyps after 4 years in my tanks. But TR Julidochromis seem to have reached full growth at 3+ years and are really hitting peak spawning from the looks of things. I've heard tale of 10+ year old shellies, but again they were male specimens. I have 6 year old calvus that are still growing, so who know's how long they'll last.
I think longevity depends primarily on the stressors they've faced. Can anyone confirm my theory that TR last longer than WC fish?