Deuterostome Phylogeny

Echinodermata

A phylum that includes sea stars, sea urchins, sea cucumbers, sand dollars, and brittle stars.

Pentaradial symmetry

A body symmetry characteristic of adult echinoderms, where the body can be divided into five equal parts.

Urochordata

A subphylum that includes tunicates, characterized by sessile adults and larvae that possess all five vertebrate characteristics.

Tunicates

Marine animals that are part of the Urochordata subphylum, known as filter feeders that are sessile in adulthood.

Cephalochordata

A subphylum that includes sea lancelets, which retain all five vertebrate characteristics throughout their life.

Agnatha/Cyclostomata

A superclass of jawless fish that includes lampreys and hagfish, characterized by having cartilaginous structures instead of bones.

Jawless

Referring to fish such as those in the Agnatha/Cyclostomata group that lack jaws.

Cartilaginous

Describing the skeletal structure of jawless fish like those in the Agnatha/Cyclostomata group, which have cartilage instead of bone.

Chondrichthyes

-sharks and rays

-cartilaginous skeleton

-placoid scales

Osteichthyes

-bony fish

-swim bladders

-Actinopterygii - ray finned fish(Perch)

Sarcopterygii

-Coelacanths and Lungfish

Amphibia

-Anapsid skulls

-Incompletely terrestrial

-can have lungs or gills

-lay eggs in water, external fertilization

Reptilia

-tough, keratinized skin

-hard shells

-diapsid (except for turtles)

Mammalia

-internal fertilization

-produce milk from mammary glands

-Mostly live born offspring