er Apoda Caecilians -no limbs or girdles -burrowers (fossorial) -short or absent tail -terminal vent -no or few caudal vertebrae -small eyes -eyes under the skin or under the skull -annular grooves have tiny dermal scales -no gills in adults -protrusible male sex organs (called phallodeum); thus internal fertilization -tentacle between eye and nostril -outgrowth of the brain, tactile in function - 6 families; 33 genera and 163 species
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Order Apoda Caecilians - no limbs or girdles -burrowers (fossorial) -short or absent tail
Order Apoda Caecilians - no limbs or girdles -burrowers (fossorial) -short or absent tail -terminal vent -no or few caudal vertebrae -small eyes -eyes under the skin or under the skull -annular grooves have tiny dermal scales -no gills in adults - PowerPoint PPT Presentation
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Order ApodaCaecilians-no limbs or girdles-burrowers (fossorial)-short or absent tail-terminal vent-no or few caudal vertebrae-small eyes-eyes under the skin or under the skull-annular grooves have tiny dermal scales-no gills in adults-protrusible male sex organs (called phallodeum);
thus internal fertilization-tentacle between eye and nostril
-outgrowth of the brain, tactile in function
- 6 families; 33 genera and 163 species
Skull completely roofed, exceptopening for sense organs, little kinesis
Skull with temporal region openings; slightly kinetic
in bony sockets beneath skin-tentacle arises near anterior edge of eye-short tail-200 – 300 mm TL-oviparous-deposits aquatic eggs
Epicrionops
Family IchthyophiidaeAsian Tailed Caecilians- SE Asia, India and Indonesia- oviparous- conspicuous annuli; mostly 200-300 mm TL- Ichthyophis glutinosus-very common-forest lowland streams-burrow in banks, lay 15-20 eggs in burrows-female coils around eggs-larvae hatch and enter water-larvae are gilled-upon transformation lose gills and become worm-like
Ichthyophis
Family CaecilidaeTailless Caecilians21 genera
-Seychelles-SA, Africa, and SE Asia-oviparous or viviparous-larval period 10-12 months-terrestrial as adults-no tails
Siphonops
Family TyphlonectidaeWater Caecilians5 genera; 13 species
-small eyes are hypodermal- dermal scales absent in the grooves- sensory tentacle small; closer to nostrils
than the eye-largest caecilians - 300 mm-800 mm-S. America- all viviparous
-R. Nussbaum at U of Mich
Typhlonectes
Family Scolecomorphidae1 genus - Scolecomorphus
-E and W Africa (sub-Saharan Africa)-tailless; eye covered with bone-large tentacle can be extended-oviducts w/ small eggs but bigger embryos-ovoviviparous-developing embryo nourished by mom
Family Uraeotyphlidae – Kerala Caecilians
1 genus – Uraeotyphlus- 200 – 300 mm TL- scales present in annular grooves- short tail- eat earthworms and insects