KINGDOM ANIMALIA PHYLUM CHORDATA SUBPHYLUM VERTEBRATA CLASS AMPHIBIA

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KINGDOM - ANIMALIA PHYLUM - CHORDATA SUBPHYLUM
VERTEBRATA CLASS - AMPHIBIA
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AmphibiansGeneral Characteristics

• Amphibia means double life
• All under metamorphosis
• Young are fish-like, herbivores with 2-chambered
  heart
• Adults are carnivorous, can live on land, have
  lungs, 3-chambered heart
• Cold-blooded or exothermic (poikilothermic)
• Smooth, moist skin
• Webbed feet without claws (most)

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Three Orders of Amphibia

• Gymnophiona
• meaning gymnos naked, opineos of a snake
  aka Apoda
• Example Caecilians
• Urodela (aka Caudata)
• meaning oura tail, delos evident
• Example Salamanders
• Salientia (aka Anura)
• meaning an without, oura tail
• Example Frogs and Toads

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Order Gymnophiona (Apoda)Caecilians

• 160 species
• Only found in tropics
• Look like large worms
• Small eyes or totally blind
• Hearing is not good - rely on tentacles (located
  between eye and nostril)
• Excellent sense of smell
• Live in burrows (seldom seen by humans)
• Fertilization is internal
• Oviparous - lay eggs in puddles

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Caecilian
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Caecilian
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Order Caudata (Urodela)Salamanders and Newts

• 360 species
• Long slender body with tail
• Aposematic (warning) coloration
• deaf - feel vibration on ground
• Temperate climates, tropics of Central and
• South America
• Often confused with lizards they are not lizards
  because they undergo metamorphosis, have no
  scales, no claws, and four toes on foot
• American Hellbender largest in North

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Hellbender
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CaudataCommon Names

• Salamander any type
• salamander means fire animal - because men
  brought wood into house and stacked it near fire
  salamanders crawled out from under the bark
• Axoltol sexually mature, but still has some
  larval characteristics (gills)
• Newt
• Eft - Juvenile term the juvenile is in a land
  body form and uses skin for respiration
• Newt - adult term the adult is in water body
  form
• Some Red eft are poisonous (the adult loses the
  poisonous skin)
• Newts live in grassy or weedy ponds
• Adults are olive green with a yellow belly
• Newts are easier to hold than other salamanders
  because their skin is rougher and less moist

Salamander
Red Eft
Newt
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CaudataBreeding Habits

• Oviparous egg laying
• Internal fertilization male deposits packet of
  sperm (spermatophore), females body picks it up
  in her cloaca
• Eggs laid in water, covered by coat of jelly-like
  material to prevent drying out
• Direct development bypassed larval stage
  (strictly for land salamanders)

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CaudataDevelopment of Egg

• Cleavage of zygote (1 fertilized cell, into 2
  cells, then 4, 8, etc)
• Blastula (hollow ball of cells)
• Blastopore (hole in blastula becomes anus) so
  they are deuterostomes
• Gastrula double layered sac
• Paedomorphosis may retain larval form (gills)
  when sexually mature
• Ex Mudpuppy (genus Necturus)

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Order Anura (Salientia)Frogs and Toads

• 3,450 species!
• Found in most habitats except polar and subarctic
  zones

FROG
TOAD
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Toads

• Dry skin
• Nocturnal
• Poison glands in skin (not effective on snakes)
• No teeth
• Tadpoles (called polliwogs) are usually black

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Frogs

• Hibernation spend cold months buried in mud
  below the frost line, live off of stored fat,
  breathe through skin
• Estivation during high heat bury in mud or
  deep water

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Order Anura Divisions

• Divided into 21 families
• Ranidae the most common (frogs)
• Hylidae (tree frogs)
• Bufonidae (true toads)
• Largest West African Toad 30cm long, eats
  rats
• Smallest Psyllophyrne lt1cm long
• Largest American frog Bullfrog
• Scientific name Rana catesbelana

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Anura Skin

• Thin, smooth, moist (frog)
• Used in respiration
• Contains three different types of chromatophores
  (pigment cells)
• Contains mucus glands to prevent dryness
• Contains chemical and tactile receptors

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Anura Sensory

• External Nares nostrils
• Olfactory membrane lining in nasal cavity
• Tympanum external eardrum
• transmits vibrations
• Eustachian tube connects pharynx to middle ear
• Eyes
• dominant sense
• have color vision, moving upper and lower lids
• Protective covering over eye for underwater
  vision (called the nictitating membrane)
• Tongue
• taste buds on tongue

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Anura Skeleton

• Vertebrae (3 types)
• Cervical neck
• Sacral help support hind legs
• Urostyle fused coccyx (triangular bone at the
  bas of the spinal column tailbone)
• Skull includes brain case, face, and jaw
• Pectoral girdle front legs, breast bone, collar
  bone, shoulder blades
• Pelvic girdle hip bones (fused), hind legs

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AnuraNervous System

• More highly developed than fish
• Brain
• Forebrain (olfactory, cerebrum)
• Olfactory smell
• Cerebrum of little importance to frogs and
  toads
• Midbrain (optic lobes)
• Optic lobes vision and complex activities
• Hindbrain (cerebellum, medulla)
• Cerebellum equilibrium and balance
• Medulla oblongata auditory reflexes,
  respiratory, swallowing, vasomotor control
  (nerves and muscles that cause the blood vessels
  to constrict or dilate)

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AnuraDigestive System

• carnivorous (insects, spiders, worms, slugs,
  etc)
• Tongue is sticky
• Swallows prey whole
• Teeth in upper jaw only
• Vomerine 2 large teeth
• Maxillary small, on rim of upper jaw
• Gullet (opening to esophagus)
• Esophagus
• Stomach (digestion begins)
• Pylorus (valve between stomach and intestine to
  prevent early passage of food out of stomach)
• Intestine (small)
• Duodenum (pancreas and bile secrete into this)
• Ileum (coiled portion)
• Mesentery (holds intestine in place)
• Colon (large intestine) stores undigested food,
  absorbs water
• Cloaca bottom portion of colon, receives
  reproductive products, kidney products, can take
  in water to absorb from environment
• Accessory organs
• Liver stores sugar in the form of glycogen
  produces bile which is stored in the gall bladder

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AnuraExcretory System

• Kidney excrete nitrogenous waste maintain salt
  and water balance
• Carbon Dioxide excreted through skin
• Urine from kidneys stored in urinary bladder

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AnuraRespiratory System

• 3 ways to obtain oxygen
• Skin (cutaneous breathing) at rest
• Mouth (buccal breathing) when active
• Lungs (pulmonary breathing) when active
• Pathway of air
• Nares, pharynx, glottis (opening to trachea),
  trachea, bronchi, alveoli (air sacs)
• Male vocal cords better developed, found in
  larynx, used to attract females

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AnuraCirculatory System

• Adult has a three chambered heart
• 2 atria
• 1 ventricle

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AnuraReproductive System

• Female
• Ovary next to kidney
• Coiled oviduct (transport egg from ovary to
  cloaca)
• Ovisac thin walled sac that stores eggs
• Eggs have a jelly-like coating and leave body
  through cloaca
• Male
• Oval testes on anterior ventral side of kidney
• Sperm ducts attach testes to kidney
• Breeding Habits
• Fertilization is external
• Male clamps onto females body from behind with
  forearms (called amplexus)
• Male releases sperm as female releases eggs