Lewis & Short

formīco, āre, v. n. [formica].

  1. * I. To creep or crawl like ants: venarum inaequali aut formicante percussu, Plin. 7, 51, 52, § 171.
  2. * II. To feel like the creeping of ants, μυρμηκιζω: donec formicet cutis, Plin. 30, 13, 41, § 120.