Lissamphibia: Caecilians, Salamanders & Frogs Flashcards
What are Lissamphibia
A group of amphibians including frogs, toads, salamanders, newts, and caecilians, often described as the “perfect water/land transition.”
What are three major characteristics of Lissamphibia?
- Still need water for eggs and larvae, and due to thin skin.
2.Respiration can occur across the skin. - Ectothermic.
How is the skeleton of Lissamphibia adapted for land?
Strong vertebrae with little flexibility, providing protection, muscle attachment, and enabling jumping and swimming.
What are the main respiratory mechanisms in Lissamphibia?
Cutaneous (skin) respiration.
Buccopharyngeal breathing.
Pulmonary respiration.
External gills in some stages
What is double circulation in Lissamphibia?
Their three-chambered heart has two atria and one ventricle, resulting in blood flow in both directions within the ventricle.
What is unique about hearing in Anurans (frogs and toads)?
They use a tympanum for high-frequency sounds and can also hear low frequencies via lungs and forelimbs
What are the three modern orders of Lissamphibia?
Order Gymnophiona (caecilians).
Order Caudata (newts and salamanders).
Order Anura (frogs and toads).
What are the characteristics of Order Gymnophiona (caecilians)?
Limbless, tropical, burrowing, with internal fertilization (oviparous or viviparous).
What are the key features of Order Caudata (salamanders and newts)?
Limbs at right angles, varied size, ability to regenerate limbs, and reproduction through spermatophores
What is paedomorphosis? Give examples.
Retaining larval traits (e.g., gills) in sexually mature adults. Examples: Mudpuppies and axolotls.
What are some adaptations for jumping and swimming in Order Anura?
Shortened vertebral column, urostyle for stability, and muscles attaching to transmit force.
How do frogs perform external fertilization?
Through amplexus, where males release sperm and females release eggs in water.
What are some “weird” reproductive strategies of frogs?
Carrying eggs on their back.
Males carrying tadpoles in their mouths.
Internal breeding pouches where young emerge from the back.
What is the life cycle of frogs (Anura)?
Cleavage and embryo development.
Tadpole with tail and external gills.
Spiracle develops and limbs emerge.
Tail is reabsorbed during metamorphosis.
Sexual maturity at 2-3 years.
