Herpetology Unit 2

Carnivores of vertebrates assimilation rate

90%

Salamander feeding preference

Soft-bodied inverts

Carnivores of vertebrates assimilation rate

90%

Salamander feeding preference

Soft-bodied inverts

Oophagy

The practice of consuming unfertilized eggs, as seen in Dendrobatid tadpoles.

Caudal Autonomy

The ability of some lizards and other reptiles to shed their tail as a defensive mechanism.

Vomerolfaction

The use of the tongue to sample non-volatile molecules, particularly important in squamates.

Compensatory Suction

A feeding mechanism that creates negative pressure to draw prey into the mouth.

Inertial Suction

A feeding mechanism that creates an inward flow of water by the expansion of the neck.

Projectile Tongues

Feeding adaptation in frogs, salamanders, and chameleons that uses elastic energy to shoot the tongue at prey.

Mechanical Pulling

A method of feeding in some frogs where muscles contract to draw the tongue back to ingest prey.

True Constriction

A feeding strategy in which an organism squeezes its coils around its prey to immobilize it.

Venom

A poisonous substance secreted by some animals, used to immobilize or kill prey.

Colubrids

A family of snakes that possess Duvernoy’s gland and are known for various methodologies of venom delivery.

Elapids

A family of venomous snakes with short, non-retractable fangs and neurotoxic venom.

Crocodilian Feeding Mechanism

Crocodilians feed by lifting their heads and using their shorter, rounder jaws to exert strength.

Gill Filters

Structures that help anuran tadpoles filter food and scrape algae from surfaces.

Tympanic Membranes

Allows frogs and crocs to sense vibrations in air and substrate.

Omnivory

The eating behavior characterized by the consumption of both plant and animal matter, common in lizards and turtles.

Specialized Herbivores

Herbivorous animals with adaptations such as gut flora for fermentation and robust teeth for grinding food.

Pit Vipers

A group of venomous snakes that use infrared radiation to detect warm-blooded prey.

Lateral Line System

A sensory system in some aquatic animals that detects water movements and vibrations.

Tortoises' Feeding Adaptation

Tortoises have akinetic skulls and can generate considerable bite force without teeth.

Snail eaters

Upper jaw is braced with braincase to pull out of shell or just crush snail with jaws

Cannibalism

Most common in amphibians

Herbivore teeth

Robust and blade-like

Active amphibian hunters

Search for prey that move constantly

Herbivore distribution

Concentrated in warmer climates

Omnivory

Most common in lizards and turtles

Lizard pollinators

Important on islands lacking nectarivorous birds

Active foraging

Move fast and frequently for hidden prey

Ambush amphibians

Look for small jerky prey

Ambush predators

Use vision, more likely to consume toxic prey. Short squat and cryptic features

Compensatory suction

Prevents a pressure wave and uses negative pressure to trap prey by expanding the oral cavity.

Inertial suction

Accommodates water and creates an inward flow by expansion of long neck

Neustophalia

Skim small floating items from water’s surface

Terrestrial turtles

Akinetic skulls, no teeth but sharp beak, and strong bite force

Trochlear process

Adductor muscles wraps around to pulley jaws with minimal effort for lepidosaurs (Squamata & Rhynchocephalia)

Salamander larvae and larval caecillians

Use labial lobes to seal sides of mouth to prevent escape of water and prey

Anuran tadpoles diet

Primarily algae

Anuran tadpole feeding adaptations

Gill filters filter food and use keratinous mouth scrapers

Pipid frogs

Use negative suction and shove prey in with forelimbs

Caecillian jaw mechanics

Retroarticular process and enlarged interhyoid muscle for increased biteforce

Caecilians on large prey

Use rotational feeding

Lingual prehension

Tongue is slapped on prey

Plethodontids feeding

Tongue projector muscles contract around Y shaped hyobrachial skeleton, firing tongue rapidly

Mechanical Pulling

Uses contracting muscles. Tongue only slightly protrudes beyond jaws

Inertial elongation

Tongue is flung forward and downwards, muscles stiffen at tongue’s tip

Hydrostatic elongation

Tongue functions as muscular hydrostat in multiple directions. Characteristic of myrmecophages

Lizards jaws

Loss of tower temporal arch allows movement of quadrate

Inertial feeding

Head is tilted back, monitors and tegus

Scolecophidian snakes

Feed on large quantities of small prey. Small prey and small gape, consume much ant and termite larvae

Alethinophidian snakes

Feed on larger prey, alternating jaw movements

Unilateral feeding

Prey is transported via left and right undulating jaw movements

Snail eating snakes

Extract snails with long mandible extensions with comb-like teeth

Venom uses

Immobilization, killing, digestion, defense

Colubrids

Rear fang teeth conduct venom with grooves

Elapids

Neurotoxic venom

Viperids

Tissue-toxic venom

Helodermatids

Venom glands lie along the lateral surface of mandible. Venom secreted through ducts to grooves of teeth

Hormones

Water uptake

Ammonia

Aquatic amphibians, very toxic!

Uric acid

Chief nitrogenous component of reptile waste

Urea

Most amphibians

Body water storage of amphibians

Urinary bladder and lymph sacs

Smooth skin

Aquatic amphibians

Grandular skin

Terrestrial amphibians

Pelvic regions of terrestrial frogs

Highly vascularized for osmoregulation

Heleothermy

Basking and solar radiation

Shuttling

Moving back and forth from warm to cold areas

Inertial ectothermy

Muscle activity generates heat, leatherback turtles

Convective heat exchange

Shuttle back and forth from still and moving air

Thigothermy

Surface area in contact with substrate

Supercooling

Some amphibians use glucose and glycerine as antifreeze

Supplementary respiratory structures in amphibians

Structures like hellbender lasagna sides and African Hairy Frog hairs that enhance dive time and oxygen transfer to eggs.

Aquatic turtles' pharyngeal structures

Aquatic turtles have papillae in their pharynx that resemble tadpole gills.

Cloacal respiration in pleurodires

Cloacal openings in some pleurodires are lined with papillae for gas exchange.

Direct-developing and viviparous amphibians

Embryos possess specialized gills or vascularized tails for gas exchange.

Buccopharyngeal pumping in amphibians

1. Nostrils open while buccal cavity expands

2. Glottis opens while buccal cavity compresses and lungs expand

3. Buccal cavity expands while the lungs compress

4. Glottis closes while the buccal cavity compresses

Negative-pressure ventilation

Reptiles and birds utilize negative-pressure ventilation, which draws air in by creating low pressure in the pharyngeal region.

Varanids

Use buccal pumping similar to frogs

Crocodile respiration

Liver in crocodiles acts as a piston to compress and expand the lungs.

Turtle respiration

Use their viscera to compress their lungs and inhale by expanding their visceral cavity.

Chelidae

Austro-American Side-necked Turtles, Pleurodires with long necks

Pelomedusidae

African Mud Turtles, Pleurodires analogous to Emyidids

Podocnemididae

Madagascan and South American river turtles. Flat shelled herbivores (Pleurodires)

Trionychidae

Softshell turtles: Cryptodires with flattened shells and lack of peripheral carapace shells

Carettochelyidae

Pig-nosed turtle: Cryptodire with sea turtle limbs and dome shells

Platysternidae

Big-headed turtle, Cryptodire of SE Asia

Geoemyidae

Old World Pond Turtles (Cryptodires)

Testudinidae

Tortoises, terrestrial Cryptodires

Dermatemyidae

Central American River Turtle (Cryptodire)

Cheloniidae

Hard-shelled sea turtles (Cryptodires)

Dermochelyidae

Leatherback sea turtle (Cryptodire)

Sphenodontidae

Tuatara family

Gavialidae

Gharials

Alligatoridae

Alligators and caimans, Teeth of upper jaw fit into pits of lower jaw

Crocodylidae

Notch in the upper jaw accommodates 4th teeth of the lower jaw