Shells

Great diversity existed among brachiopods in the past; modern brachiopods, however, exhibit little variety. They are commonly tongue-shaped and oval lengthwise and in cross section. The surface may be smooth, spiny, covered with platelike structures, or ridged. Most modern brachiopods are yellowish or white, but some have red stripes or spots; others are pink, brown, or dark gray. The tongue-shaped shells (Lingula) are brown with dark-green splotches; rarely, they are cream yellow and green.