Oh wow, its almost 4am here. Nevermind, I THINK I finally got it through my thick skull, and narrowed it down to the Elder Crab, and started working on variations of it. I went with five this time, trying to think what a crab clan would perceive as the distinctive characteristics of an elder for them. (please don't mind the typos, I am a bit tired now).
I went with 3 main characteristics, besides age (which, granted, would be difficult to perceive for an animal with its skeleton on the outside): weight, shell size, pincer size.
Weight would mean a prosperous individual, who is beyond survival now and therefore can use only his cunning to stay ahead.
Shell size is a symbol of status and territory: the bigger the house, the more important the individual. Since an oversized shell becomes impossible to carry, it means that it has stablished at that place and is stable and beyond petty squanders.
A huge pincer would be the closest resemblance to age for many crab species; a big pincer means a strong individual, who has survived many battles without losing it and growing it again. by making it huge, it represents the individual has grown past a certain age where it is no longer seeked for battle but for its wisdom.
In the end, I added adorning characteristics like the runes to give the crabs an air of mysticism and to reinforce the idea of ages wisdom, and a scepter to make the idea of commandeering more clear.
Now all is left is to chose one of these for the next steps! Anyone, any ideas? Horia? Did I did right this time? =)