Invertebrate Macro Fossils Lab Flashcards

Phylum Porifera

• Composed of sponges, characterized by a skeleton that provides structural support.

Phylum Cnidaria

• Includes various organisms such as corals, anemones, jellyfish, and hydroids.
• Divided into subclasses including Anthozoa.

Cnidaria: Anthozoa

• Benthic marine suspension feeders, primarily living on the sea floor.

Cnidaria: Anthozoa: Rugose Corals

• Existed from the Ordovician to Permian periods; now extinct.

Cnidaria: Anthozoa: Tabulate Corals

• Known for their colonial forms, which create a distinctive honeycomb appearance.

Cnidaria: Anthozoa: Scleractinian

• Also known as Hexa-corals; resemble rugose corals but have different skeletal structures.

Phylum Mollusca

• Highly diverse group of invertebrates including various classes.

Mollusca: Gastropod

• Represents slugs and snails that typically exhibit a coiled body structure.

Mollusca: Bivalvia

• Composed of clams, characterized by two shells hinged together.

Mollusca: Cephalopoda

• Includes squids, octopuses, and chambered nautilus, known for their complex behavior.

Mollusca: Cephalopoda: Nautiloidea

• Features shells that can be straight, coiled, or comprise septa to divide chambers.

Septa

• Refers to the partitions that separate the chambers within nautiloid shells.

Phylum Bryozoa

• Resembles sponges or corals; closest living relatives to brachiopods.

Phylum Brachiopoda

• Characterized by two shells held together either by muscle or a peg-and-socket hinge.

Brachiopoda: Inarticulate Brachiopods

• Shells are connected solely by muscles without a hinge mechanism.

Brachiopoda: Articulate Brachiopods

• Feature a peg-and-socket hinge for connecting the two shells.

Phylum Arthropoda: Crustacea

• Encompasses crabs, shrimp, lobsters, and barnacles, all of which have jointed limbs.

Arthropoda: Crustacea: Cirripedia

• Specifically refers to barnacles that serve as benthic marine suspension feeders.

Phylum Echinodermata

• Includes starfish, sea urchins, and similar organisms characterized by a unique body structure.

Echinodermata: Crinoidea

• Known as sea lilies or feather stars, resembling flowers in appearance.

Echinodermata: Echinoidea

• Comprises sea urchins featuring a spherical or flattened globular body shape.

Mollusca: Cephalopoda: Ammonoidea

• Characterized by septa and sutures displaying a wavy pattern.

Mollusca: Cephalopoda: Belemnoidea

• Distinct for their solid, cigar-shaped structures.

Phylum Arthropoda

• Defined by segmented bodies and an external skeleton providing protection and support.

Arthropoda: Trilobita

• An extinct class of marine arthropods featuring a three-part body: head, thorax, and tail.