Agnatha

BASIC MORPHOLOGY A cartilaginous teleost This species of Triggerfish is seemingly unattractive. They are a highly compressed ovular species and are largely a dull gray color. A bright white line extends from its mouth to the anal fin dividing the darker gray above and the lighter gray below. The darker patterning on their body can be speckled, bars, or hardly visible. Their bottom jaw is exceptionally pale compared to the rest of their body and their eyes are set within a pale blue rim. http://saltaquarium.about.com/od/triggerfishprofiles/p/prgraytrigger.htm Their mouth is small and beaked, capable of crushing the exoskeletons of their prey. Each jaw has four teeth on either side while the upper jaw also contains six plate-like pharyngeal teeth. Their eyes are set at the top of their head and are independently controlled. (Wiki) The name Triggerfish is the common name for the family Balistidae which it has acquired because of a unique synapomorphy, the presence of dorsal spines used to keep them inside hiding spots. http://animals.nationalgeographic.com/animals/fish/triggerfish/ “Their anterior dorsal fin is reduced to a set of three spines.” They have rhomboid scales, forming an armour over their body (wiki), and giving them a rough sandpaper like qualityhttp://portal.ncdenr.org/web/mf/triggerfish-gray. They have a peculiar covering of gill plates shared by members of the Tetradontae order. (Wiki) TRIGGER The first two basal pterygiophores fuse completely during…

The subphylum Vertebrata includes all the familiar animals we tend to see everyday, and some rare and unusual ones (O’Neil, 2012). Scientists classify the seven different Vertebrates based on their skeletal system, general environmental adaptation, and reproductive systems. These seven Vertebrates include, Agnatha, Chondrichthyes, Osteichthyes, Amphibia, Reptilia, Aves, and Mammalia. During the lab dissection, the class dissected organism from only four of these classes. First, we dissected the…