Lewis & Short

conchȳlĭātus, a, um, adj. [conchylium].

  1. I. Of a purple color: peristromata, Cic. Phil. 2, 27, 67: vestis, Plin. 9, 39, 64, § 138; Suet. Caes. 43: lana, Petr. 54, 4; Marc. Emp. 9.
  2. II. Clothed in purple: relictis conchyliatis cum illo seminudo loquor, Sen. Ep. 62, 3.