a. External examination - sketch and label the following features:
pedicle valve, brachial valve, hinge line, interarea, commissure, growth lines, plane of symmetry, pedicle opening
b. Internal examination - identify the following features, and know their various functions.
mantle, mantle canals, didcutor muscles, adductor muscles muscle scars, lophophore, brachidium, mouth, pedicle
2. Note and describe how the shape of the brachidium and lophophore is often reflected in the shape of the brachiopod's shell (use models if available).
3. Class Inarticulata, Order Lingulida, Lingula. The morphology of this brachiopod has persisted relatively unchanged since the Cambrian. Note the extensive pedicle. What is Lingula's mode of life? Do you think it fair to refer to this animal as a "living fossil"?
4. Class Articulata, Order Strophomenida, Suborder Productidina. What morphological feature do the shells of these productids share? What function did these structures serve?
5. Sketch and label the following features:
7. Brachiopod shells are described as convex, planar or concave. The shape term for the brachial valve precedes that for the pedicle valve. For example, a brach with a convex brachial valve and a planar pedicle valve is called "convexi-planar". Sketch the following brachiopod shell shapes, labeling brachial and pedicle valves: biconvex, plano-convex, concavo-convex.
8. Brachiopod classification. The phylum Brachiopoda is divided into two classes, Inarticulata and Articulata. You need to be able to recognize these classes, the important orders within them, and the geological ranges of the classes and orders.
For each order, make a short list or table of features that might help you distinguish it from the other orders (shell shape, shell outline, development of ribs, growth lines, size of interarea, length of hinge line, prominence of fold and sulcus, shape of commisure, etc.). Sketches are helpful also.
9. Brachiopods had a variety of modes of life. Match up the specimens with their corresponding mode of life. Make use of shell features, if necessary:
| Taxa | Mode of Life |
| a. Lingula | 1. epifaunal: free-lying |
| b. a spiny productid | 2. epifaunal: attached by pedicle |
| c. Terebratalia | 3. infaunal |
| d. Spirifer | 4. semi-infaunal |
Back to Chapter Eight.