fossils 3.2

These flashcards cover the vocabulary and key concepts related to brachiopods as discussed in the lecture on fossils.

Brachiopods

Marine organisms with two shells (valves), distinguished by the structure and composition of their shells and feeding apparatus.

Lophophore

A feeding organ in brachiopods used for filter and suspension feeding.

Pedicle

A stalk-like structure in brachiopods that anchors them to the substrate.

Delthyrium

An opening in the shell of a brachiopod that provides access for the pedicle.

Bivalves

Another class of marine organisms that have two shell valves, typically distinguished from brachiopods by symmetry and other morphologies.

Symmetry

The arrangement of body parts; brachiopods can be asymmetrical or bilaterally symmetrical, unlike many bivalves.

Musculature

The muscle structure in brachiopods that helps them open and close their shells.

Teeth

Surface features on the hinge of a brachiopod shell that aid in alignment and stability.

Ecological niches

The roles and positions that brachiopods occupy in their ecosystems, differing from bivalves.

Subphylum Linguliformea

A subphylum of brachiopods characterized by inarticulate shells made from calcium phosphate.

Order Orthida

An order of articulate brachiopods known for their calcite shells and strophic hingeline.

Order Spiriferida

An order of articulate brachiopods characterized by biconvex shells and well-developed interareas.

Cenozoic Era

The current geological era; includes phases of brachiopod diversity.

Infaunal

Describing organisms that live buried in the substrate; some brachiopods exhibit this behavior.

Epifaunal

Describing organisms that live on the surface of the substrate; some brachiopods attach using a pedicle.

Calcareous support

Material that provides structural support for the brachiopod's feeding apparatus.

Hinge axis

The line around which the valves of a brachiopod articulate.

Brachidium

A calcareous support structure within the lophophore of some brachiopods.

Commissure

The line where the two valves of a brachiopod meet.

Deltidal plates

Plates that close the delthyrium in some brachiopods.