Zoology Lab Exam 3 - Echinoderms/Hemichordata/Chordata ID

BIOL 230 - Spring 2026 - Echinoderms/Hemichordata/Chordata

Identify

Phylum: Echinodermata

Class: Asteroidea

Sea Star dissection

Oral end - note the tube feet, the center mouth, and the ambulacral grooves

Identify

Phylum: Echinodermata

Class: Asteroidea

Aboral end - not the off center madreporite (sieve plate), the central anus, and the dermal ossicles (spine)

Identify

Phylum: Echinodermata

Class: Asteroidea

Note the lighter cardiac stomach, the pyloric cecum running into the arms, and the bony skin

Identify

Phylum: Echinodermata

Class: Asteroidea

Pink - madreporite

Yellow - ambulacral ridge

Orange - ampulla (helps with the tube feet water)

Green - pyloric cecum

Blue - stomach

Identify

Phylum: Chordata

Subphylum: Vertebrata

Superclass: Agnatha

Atlantic sea lamprey dissection

Note the mouth, consisting of an oral funnel with horny teeth and sensory papillae surrounding it

Identify

Phylum: Chordata

Subphylum: Vertebrata

Superclass: Agnatha

Atlantic sea lamprey dissection

Pineal body, used for sensing light as well as a singular nostril in front of it

Identify

Phylum: Chordata

Subphylum: Vertebrata

Superclass: Agnatha

Atlantic sea lamprey dissection

Yellow - kidneys

Blue - gonad (this is a male)

Red - intestine

Green - liver

Identify

Phylum: Chordata

Subphylum: Vertebrata

Superclass: Agnatha

Atlantic sea lamprey dissection

Yellow - kidneys

Blue - gonad (this is a male)

Red - intestine

Green - liver

Identify

Phylum: Chordata

Subphylum: Vertebrata

Superclass: Agnatha

Atlantic sea lamprey dissection

Dark blue is the heart surrounded by the pericardium

Identify

Phylum: Chordata

Subphylum: Vertebrata

Superclass: Agnatha

Atlantic sea lamprey dissection

Purple - brain

Orange - heart

Dark blue - pharynx

Yellow - pineal gland

Red - Spinal cord

Pink - Myotome cord

Blue - notocord

Identify

Phylum: Chordata

Subphylum: Cephalochordata

Branchiostoma aka amphioxus (lancelet)

Not the oral hood with tentacles, the rostrum, the wheel organ, the pharyngeal slits/bars, the dorsal nerve cord and the lower notochord

Identify

Phylum: Chordata

Subphylum: Cephalochordata

Branchiostoma aka amphioxus (lancelet)

Not the hepatic cecum, the dorsal nerve cord, and the notochord

Identify

Phylum: Chordata

Subphylum: Cephalochordata

Branchiostoma aka amphioxus (lancelet)

Note the atriopore, the intestine, the anus (way at the back, the bump), and the myomere in the tail muscle

Identify

Phylum: Chordata

Subphylum: Vertebrata

Superclass: Agnatha

Atlantic sea lamprey ammocetes larva

Note the oral hood, the brain, the eye, the notocord and the dorsal aorta under it, as well as the prominent pharyngeal bar. Also note the heart which has been cut off at the end (the bump on the ventral side)

Identify

Phylum: Chordata

Subphylum: Vertebrata

Superclass: Agnatha

Atlantic sea lamprey

Note the nerve cord, the myomeres, the cloaca, the coelom, and the intestine

Identify

Phylum: Chordata

Subphylum: Cephalochordata

Branchiostoma aka amphioxus (lancelet)

Coming up from bottom to top but slide is flipped

Note the dorsal fin (at the bottom) and then the nerve cord and then the large notochord all surrounded by the myomere. The large purple line area is the pharynx while the filled in purple areas are gonads. The hepatic cecum is to the right over the gonad in the middle and the nephridia are closer to the notochord off to the side.

Identify

Phylum: Echinodermata

Class: Ophiuroidea

Serpent Star

Identify

Phylum: Echinodermata

Class: Echinoidea

Assorted sea urchins

Identify

Phylum: Echinodermata

Class: Echinoidea

A sea urchin’s Aristotle’s lantern. It helps with feeding by rasping algae off various surfaces

Identify

Phylum: Echinodermata

Class: Echinoidea

Various sea urchins - note the Aristotle’s Lantern (1) , teeth, test (2) , tube feet (3) , madreporite (4) , anus (6) , and gonad (7)

Identify

Phylum: Echinodermata

Class: Echinoidea

Assorted sand dollars - test is equivalent to their shell

Identify

Phylum: Echinodermata

Class: Echinoidea

Sea biscuit

Identify

Phylum: Echinodermata

Class: Holothuroidea

Sea cucumber

Note the body, tube feet, mouth, tentacles, and anus

Identify

Phylum: Echinodermata

Class: Holothuroidea

Sea cucumber

Identify

Phylum: Echinodermata

Class: Crinoidea

Feather star - note the five rays to form ten arms. Cirri erupt from the aboral surface, while a cup-like calyx is surrounded by the arms. They stand oral side up and are sessile

Identify

Phylum: Hemichordata

Class: Enteropneusta

Acorn worm - note the short proboscis by the bumpy side as well as the collar (the bumps) and the trunk (the long bits)

Identify

Phylum: Chordata

Subphylum: Urochordata

Various sea squirts

Identify

Phylum: Chordata

Subphylum: Urochordata

Cynthia - a sessile tunicate

Identify

Phylum: Chordata

Subphylum: Urochordata

Cynthia - a sessile tunicate

Identify

Phylum: Chordata

Subphylum: Urochordata

Molgula - Another sessile tunicate - note the incurrent and excurrent siphons

Identify

Phylum: Chordata

Subphylum: Cephalochordata

Preserved lancelets

Identify

Phylum: Chordata

Subphylum: Cephalochordata

Preserved lancelets

Identify

Phylum: Chordata

Subphylum: Cephalochordata

Preserved lancelet

Identify

Phylum: Chordata

Subphylum: Urochordata

A salp (floating tunicate). Typically lives in large colonies in the ocean

Identify

Phylum: Chordata

Subphylum: Urochordata

Tunicate larva - has all fic chordate characteristics

Identify

Phylum: Chordata

Subphylum: Vertebrata

Superclass: Agnatha

Atlantic sea lamprey dissection

Red - nerve cord

Yellow - notocord

Orange - vessel

Identify

Identify