In both Teloschistes and Caloplaca you find round, orange apothecia (the structures in which the fungal partners produces spores). Ignore the apothecia and concentrate on the rest of the lichen ( i.e. the thallus). In Caloplaca the the thallus is usually flattish and may look like little more than a coat of paint or may be a thicker and often lobed sheet. A Teloschistes thallus is branched and somewhat shrubby (perhaps with just short, wispy branches).