Chapter 12- Lissamphibia (Salamanders, Anurans and Caecilians)

four fingers or fewer

What specific feature distinguishes Lisamphibians (amphibians) from other species on a phylogenetic tree?

Permian

Which era was the first amphibian fossil was observed?

True

True or False: oldest true frog fossils date to 190mya, but froglike vertebrates are known from 200 mya

Jurassic

Which era was the oldest salamander fossil dated?

True

True or False: Caecilian fossils are scarce but the oldest known are from 195 mya

biphasic life cycle

having two distinct phases or stages in a life cycle

anamniotic eggs

primitive vertebrate eggs that lack the specialized protective membranes, specifically the amnion

Anura (frogs & toads)

Order of amphibians that lack tails

Caudata or Urodela (salamanders)

Order of amphibians that have tails

Gymnophiona (caecilians)

Order of amphibians that means “naked snake”

seat (pelvic) patch

a specialized region of skin on the ventral surface around the pelvis that is highly permeable to water and allows water to flow rapidly into a dehydrated animal

Aquaporins

these structures is inserted into the plasma membranes to channel the movement of water

mucous glands

continuously produce mucopolysaccharides, helps keep the skin moist and able to function in gas exchange when the animal is out of water, and may also have anti- predator benefits as it makes the animal slippery and difficult to grip

granular (poison) glands

produces noxious and sometimes toxic secretions; these glands are often grouped together and give the skin a textured appearance

epibatidine

a powerful painkiller that has been isolated from a poison dart frog (200x more powerful than morphine)

magainin

a bacteria-killing antibiotic peptide

aposematic

warning coloration

mimicry

an evolutionary adaptation where one species develops a superficial resemblance to another

cryptic

resembling its environment; “camouflage”

batesian

harmless species that starts to look like aposematic species

Müllerian

two different species take on similar warning coloration

on the sides of the head

Where are the gills exposed and projected in larval salamanders and caecilians?

neoteny

type of paedomorphosis; a phenomenon brought about by the maturation of the reproductive system in a larval form that fails to undergo metamorphosis

Paedomorphosis

retention of ancestral juvenile characteristics in a descendant adult species

Paedogenesis

reproduction in the larval state

force pump mechanism

a different way to get air into their lungs where air enters the oral cavity through the nostrils, the nostrils close, and the floor of mouth is raised forcing air into the lungs and prevented from escaping by a sphincter muscle

Pedicellate teeth

the crown and base of amphibian teeth are made of dentine and are separated by a narrow layer of uncalcified dentine

True

True or False: most fertilization in frogs are external

Amplexus

male grasps a female with his front legs

metamorphosis

a biological process involving an abrupt, hormone-driven transformation from a juvenile, aquatic larval stage to a sexually mature adult form adapted for life on land

True

True or False: most salamanders use internal fertilization

True

True or False: most salamanders have elaborate courtship behaviors

spermatophores

what structure in male salamanders produce packets of sperm?

eft

a juvenile stage in salamanders

intromittent organ

general term for external organ for sperm delivery

Advertising Calls

territorial calls are calls made by male frogs to inform others that this is their patch and that intruders should ‘back off’! Often these calls are a low groan or are slightly different to the mating call

Distress calls

very dramatic calls made by a frog that is being attacked by a predator. These calls are usually a high-pitched scream or wail that startles a predator causing it to release the frog, allowing it to escape

Warning call

Noise that is made by a frog that has been startled or disturbed. The frog may make a short grunt or squawk as it jumps away; probably letting other frogs know that there may be some danger

Release calls

Made by frogs that have been grabbed by another frog that is searching for a mate. If a male frog is unsuccessfully trying to attract a mate, he may grab hold of any frog that moves past him. If he grabs a male frog, a female frog that has already bred or a frog of a different species, the grabbed frog will make a release call to let him know that he is wasting his time and should let go

Explosive breeding

breeding season is a few days (e.g., wood frog)

Prolonged breeding

breeding season extends for several months (e.g., green frog)

phenotypic plasticity

the ability of a single genotype to produce different morphological, physiological, or behavioral traits in response to varying environmental conditions.

Filter feeders

hover in water column (most anurans); often live in schools of kin

grazers

beaks for scraping algae off surfaces

carnivores

large beaks for biting other tadpoles

premetamorphosis

tadpoles increase in size

thyroxine

a chemical released from the thyroid to regulate metamorphosis

prometamorphosis

hind legs appear; slower growth

metamorphic climax

forelegs appear and tail regresses; rapid portion of metamorphosis (when the frog is most vulnerable)

True

True or False: Garter snakes predate metamorphosing forms of frogs compared to fully tadpole or fully frog forms

Costal grooves

the grooves present along the sides of the bodies of many salamanders. When counting them for identification purposes, include only those between the front legs and the hind legs

mental gland

a cluster of glands on the chin of a male salamander, most noticeable during the breeding season

cloaca

common passage or cavity of the digestive, reproductive, and excretory systems

nasolabial grooves

narrow grooves that extend from the nostrils to the mouth in salamanders of the family Plethodontidae

acanthal ridges

ridges (with light lines) extending from the eyes to the nostrils in members of thespecies Gyrinophilus porphyriticus (spring salamanders)

keeled tail

a salamander tail that narrows to a knife edge along its dorsal (top) surface. Common in aquatic spp

cirrus/cirri

slender longations of the upper lip on some male salamanders, one hanging below each nostril at the bottom of the nasolabial groove

nasolabial grooves

feature that aids in chemoreception in salamanders

True

True or False: The family Plethodontidae in salamanders may have arisen out of the Appalachian Mountains

zygapophyses

braces the vertebral column to limit lateral bending

urostyle

this structure is formed when the ilium has been elongated and the rearmost vertebrae have been fused into a solid rod

semimembranosus muscle

muscle in the hind leg that is designed for maximal power and speed during jump

pelobatid spade

a dark scale-like structure on the hind feet of spadefoot toads that is used for digging

toe pads

enlarged pads at the ends of the toes

tympanum

external ear drum

vertical pupil

an elliptical pupil in some frogs

warts

raised areas on the backs of some toads

webbed feet

webbing between the toes of the hind feet

Caecillians

derives from the Latin word caecus, meaning "blind"; degenerate or missing eyes: Eyes covered by skin or bone flap; limbless: burrowing, aquatic

annuli

dermal folds overlaying underlying myomeres

protrusible tentacles

found near the eyes in caecilians that is used for mechanoreception

Basilar papillae

a hair cell system that detects high frequencies

columella

vibration of this structure alone allows high-frequency noises to be heard (frogs need the tympanum for amplification)

operculum-columella unit

vibration of this structure alone allows low-frequency noises to be heard (vibration via leg bones/scapula)

True

True or False: Salamanders and frogs have ‘green’ rods in the retina that absorbs the blue wavelength

chytridiomycosis

this disease is caused by motile zoospores that form in the water and penetrate the skin

Spiral valve

guides blood toward lungs through right pulmocutaneous arch when using lungs.