Roman pikeman and spearman

[Robert Vermaat]

Forgive me but is Arrian not using kontos as a synonym for pilum?

Ah, that's the mother of all questions!

In all, to Bosworth, with whose conclusions I often disagree, a "kontos" is indeed a heavy thrusting spear, designed for use in the line and not for throwing and he maintains that Arrian's use of the term in the Acies should not (as some do) be interpreted as a peculiarly heavy pilum.

So does Wheeler, and I think that conclusion might be the best to fit the (shaky) evidence. A thrusting spear would fit Arrian's description best, even though most commentators see some sort of pilum used here. I've argued my case here:
http://www.fectio.org.uk/articles/arrian.htm

About the throwing of the kontos, any spear can be thrown, I think I've come across Polybios saying that even a sarissa can be thrown. But it's not what they were designed for, of course.