Osteichthyes Flashcards
Sarcopterygii
Class - Only 8 extant species; including 2 coelacanth species and 6 lungfish species
Sister group to the tetrapods
Sarcopterygii (class)
Internal structure of fin of Sarcopterygii
core of articulated bones; fins move independently and muscles within fin can move bones
Name the three lungfishes
Australian, African, and South African lungfish
What type of osmoregulation do marine fish partake in?
hypotonic
List steps of Marine Osmoregulation
1) Water leaves the body osmotically through gills to hypertonic ocean; 2) compensate by drinking large amounts of water; 3) secrete excess NaCl through gills; 4) Eliminate excess ions via kidneys –> becomes waste
Fish that have long gill raker structures often eat
small food
Fish that have short gill raker structures often eat
large food
List the sensory perceptions of Osteichthyes
1) Lateral line system; 2) color vision; 3) hearing through water-borne vibrations in inner ear; 4) chemoreception; 5) otoliths; 6) proprioception; 7) magnetoreception
Reproduction of Osteichthyes
External fertilization and external development; may have sequential and synchronous hermaphrodites; up to several million eggs in some species - eggs may be attached to structures, buried, layed on bottom, or brooded in mouth
List steps of the sequential hermaphroditism cycle
1) dominant female dies; 2) nondominant male changes to female; 3) new nondominant male arrives; 4) new fish arrive
(see slide)
Indeterminate Growth
No end point in growth of body size (seen in most fish)
Determinant Growth
Set endpoint in growth of body size
Sympatric Speciation
Evolution of a new species from a surviving ancestral species occurs in the same geographical space
Allopatric Speciation
Biological populations of the same species become isolated from one another
