Lab 3: Amphibians And Reptile Species Flashcards
Class Sarcopterygii
Lobe finned fish
Clade “Amphibia”* † (Undergoing revision, see your text book)
Order Caudata
(“tailed”, salamanders) Elongate, most with four limbs. Almost entirely limited to the northern hemisphere, with their greatest diversity in North and Central America. Two important trends have occurred repeatedly in the group:
a. Paedomorphosis.
b. Reduction of lungs.
Wrinkles —> increase surface area for respiration
Lungs present in most tho some lack lungs in larval stages
Can either have gills in adulthood or no gills
Pardomorphosis (neoteny or progenesis)
Many aquatic
Can be presence of metamorphoses
One family lacks lungs and gills as adults
One family hind limbs absent and front limbs reduced
Bodies can be elongated
Cryptic colouration usually
Order Anura
“tailless”; frogs and toads
webbed hind feet and well-developed hind limbs specialized for jumping (saltatorial locomotion).
Can have binocular vision or not
Parotoid glands can be present behind eyes
Can have aposematic or cryptic colouration
Can have position glands
Circle behind eyes can be that “ears”
Some may have warts
Can show parental care
Metamorphosis common
Can have unique bony plates on ends of digits
Most semi aquatic
Cutaneous Breathing
Order Gymnophiona
(legless amphibians, caecilians) – legless, burrowing or aquatic. Reduced eyes; some with small scales buried within dermis. Some with peculiar “tentacles” which lie in grooves near maxilla of upper jaw.
Small little tooth
Show parental care
Don’t really have scales
Could be confused with sirenians b/c elongated body and typically lost limbs but most don’t retain external gills like them.
If do retain gills have very different structure —> not frilly more tissue sheet like or crumpled paper looking
Clade Amniota
Have aminotes?
Order Testudinata
(Chelonia in many texts) - turtles.
Body is entirely covered by a rigid shell from which only the head, limbs, and tail emerge.
Plastron (flat lower shell) and carapace (domed upper shell) are formed from dermal plates (originating in the lower layer of the skin).
The carapace is fused to the vertebral column and is generally also covered by epidermal scales.
Jaws are toothless and covered by a horny beak.
Freshwater, marine, and terrestrial forms. Turtles are strange.
Their exact position within Amniota is under revision, but they might belong within Diapsida.
Clade Diapsida
- two temporal openings. Greatest diversity of species and life-styles occurred during Mesozoic.
Also includes the Archosaurs.
Includes reptiles and birds
Clade Lepidosauria
scaly reptiles.
Living forms include the tuatara and the squamates (lizards, amphisbaenians, and snakes).
Order Sphenodonta
tuatara. Found only on small islands off New Zealand. Nocturnal and incapable of raising their body temperature by basking. Feed mainly on invertebrates
Bumpy scales
Laying down stance
Colouration is green
Blunt mouth
Eyebrow intense
Diapsid
Ancestral body
In lepidosauria
Order Squamata
“Lizards” *†, we retain the term “lizard” for convenience of discussion.
Lizards are highly successful and display adaptations for diverse ways of life and habitats.
Epidermal scales that may be modified into horny tubercles or plates cover their body.
Diverse structure of teeth and tongues reflects diverse dietary patterns.
Leglessness evolved repeatedly among lizards and is usually associated with life in dense vegetation.
Integumentary adaptation—> modified epidermis scales like rattle scale tail and spiny scales
Ancestral body plan but also up right stance
Colouration mainly cryptic
In lepidosauria
Best diapsid can see today
Clade Amphisbaenian
burrowing reptiles found in tropical regions.
Most are legless, some have forelegs only.
Have a single tooth on upper jaw, which together with lower dentition provides this group with a specialized predatory device.
Various modifications of the snout and head for burrowing are present.
Worm lizards
Scales go around whole body arranged in rings
More rigid jaws than Serpentes
Clade Serpentes
(Serpentes) – distinct lineage of specialized, legless squamates.
Snakes differ from legless lizards, especially regarding the adaptations of the jaw that permit snakes to swallow large prey.
Most snakes are highly modified for underground habitats.
More specialized locomotion than in legless lizards, primarily due to specialized scutes on the ventral surface.
Eyelids are fused over eyes.
Differentiation of the vertebral column is lost in snakes.
Many internal structures are reduced or absent due to specialization for the serpentine life.
Combination of different shapes of scales, look at belly to tell, have 1 long scale across belly and then have top scales that are small
Can have unique jaw structures many joints that they can unhinge to eat larger prey items
Aposematic colouration
Can have venom glands in mouth area
Scales can be rough or bumpy too
Slit pupils
2 openings on nose section can be temp receptors
