A fossilized daddy longlegs was found on a tree in Burma sporting an extra long leg. This well-endowed Halitherses grimaldii was apparently engulfed in tree resin when he was about to get his freak on and became fossilized with an erection, only to be discovered in this private moment 99 million years later.
National Geographic reports on the specifics of the daddy longlegs's prolonged amorous state:
After a months-long puberty, the male harvestman Halitherses grimaldii had finally blossomed into full manhood, sporting a penis that grew to nearly half of his body length when erect.
We know about this H. grimaldii's particular package because, as announced last Thursday in The Science of Nature, he died fully aroused, his tree-side tryst interrupted by oozing resin that entombed his body in what's now a lump of amber.
Daddy longlegs or not, you should call your doctor if your erection lasts longer than 94 million years.