A small spider.[1] Also 'phalanges' is a name they give to the tips of the fingers, as Aristophanes says in Frogs: "spiders that whirl with your fingers the loom-stretched threads".[2]
Also a military unit [formed] out of 40(?) men.[3]
"Lucius the consul, who had never seen a phalanx until that occasion in the war against Perseus, often afterwards would confess to certain people in Rome that he had never seen anything more frightening [and dreadful] than a Macedonian phalanx -- and this despite having not only witnessed but also directed as many battles as anyone."[4]