Caudata nodebased name for salamanders Urodela stembased name

Caudata: node-based name for salamanders Urodela: stem-based name for salamanders 10 families, 710 species

Pyron and Wiens 2011

Salamander characteristics • Tailed, most with four limbs of approximately equal length, four digits on front limbs, five digits on hindlimbs • Aquatic, terrestrial/fossorial, arboreal • Breathe through lungs, gills, and/or skin • Sprawling gait • Large genome – 15 -90 pg (humans: 3 pg) • Limited variation in life cycles, reproductive modes • Skull: absence of postorbital, supratemporal, jugal, supraoccipital, basioccipital, ectopterygoid • Limb regeneration

• Loss of limbs • Tail reduced • Cylindrical body • Sprawling gait • Long tail • Hindlimbs = forelimbs • Upright posture • Loss of tail • Hindlimbs > forelimbs • Sprawling gait • Long tail • Hindlimbs = forelimbs

digimorph

Salamander reproduction • Internal (spermatophore) or external fertilization • Most oviparous • Most breed, lay eggs in water • Most have larval stage (tadpole) • Few have parental care • Complex courtship, pheromones spermatophore

Courtship in Ambystoma talpoideum

Mating behavior. . .

Salamander diversity

Variable characters within Caudata • External/internal fertilization (w spermatophore) • Costal grooves • Ribs unicapitate/bicapitate • Paedomorphic characters – Gills – Absence of eyelids – Tailfin, webbed feet • Chromosome number, amount of DNA

Sirenidae • two genera, 4 species • SE USA • elongate, paedomorphic external gills, lack eyelids • nonpedicellate teeth • lack pelvic girdle, hindimbs • aquatic • external fertilization

Cryptobranchidae • Andrias (2 sp: China, Japan), Cryptobranchus alleganiensis (E USA) • paedomorphic lidless eyes, (internal) gills, absence of tongue pad • aquatic • largest amphibians (1. 8 m) • external fertilization

Cryptobranchidae

Amphiumidae • • one genus, 3 species SE USA elongate, paedomorphic: lack eyelids, tongue; have (internal) gills retain both pairs of limbs (and girdles), but small limbs aquatic up to 1. 1 m long internal fertilization female parental care Two-toed amphiuma Amphiuma means

Ambystomatidae • One genus, 32 species • North America • some paedomorphic • hybrids, unisexual forms • most terrestrial as adults, some aquatic

Dicamptodontidae • • • one genus, four species NW USA large, up to 17 cm SVL eats terrestrial vertebrates facultative metamorphosis

Proteidae • two genera, six species • Italy, Slovenia, Croatia, Eastern USA • aquatic • paedomorphic, external gills, tail fin

Plethodontidae • • • 27 genera, 468 species Americas, Italy, S Korea nasolabial groove lack lungs diverse – Fossorial, terrestrial, aquatic, arboreal – Webbed feet, ballistic tongue, prehensile tail • well-studied for speciation

Plethodontidae • • • 27 genera, 433 species Americas, Italy, S Korea Nasolabial groove lack lungs diverse – Fossorial, terrestrial, aquatic, arboreal – Webbed feet, ballistic tongue, prehensile tail • well-studied for speciation

Plethodontidae

Salamandridae • 21 genera, 115 spp • N America, Europe, Asia, N Africa • Newts • poisonous skin, aposematic coloration • some with terrestrial eft stage

Rhyacotritonidae • • One genus, four species Pacific NW USA old growth coniferous forests internal fertilization Hynobiidae • • Nine genera, 43 species Asia external fertilization lungs reduced to absent

Caudata phylogeny • Duellman & Trueb (1986) – Parsimony, 30 morph characters • Larson and Dimmick (1993) – 29 morph characters, 177 n. DNA, parsimony • Gao and Shubin (2001) – 60 morph characters, 177 n. DNA, parsimony; incl. fossil taxa • Weisrock et al. (2005) – mt. DNA, n. DNA (~1300 chars); parsimony, ML, Bayesian • Wiens et al. (2005) – Morph chars (~300), n. DNA, mt. DNA; parsimony, ML, Bayesian • Frost et al. (2006), Pyron and Wiens (2011)

Pyron and Wiens 2011

Anura (Salientia): Frogs

Anura (Salientia): Frogs 6886 species

Synapomorphies of Anura • • • urostyle lack tail fused tibia and fibula fused ulna and radius hindlimbs > forelimbs Nine (or fewer) presacral vertebrae