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One of the sixteen known genera of the family Salamandridae, Taricha (otherwise known as Western Newts) is comprised of four species and two subspecies (Weisrock et al, 2006). These species include Taricha granulosa (made-up of the two subspecies T. g. granulosa and T. g. mazamae), T. rivularis, T. torosa and T. sierra, which was officially recognized in 2007 (Kuchta, 2007). Species of genus Taricha are roughly 13-20 cm long and have a warty, brown dorsal side coupled with a yellow to red ventral side depending on species (Livezey and Wyllie, 1961). The species are differentiated by characteristics such as the amount of time spent on land or in water, coloration, size of eyes and head, palatine teeth pattern, and how the newts lay their eggs (Livezey and Wyllie, 1961). All four species have an aquatic and terrestrial phase as well as a juvenile and adult stage, which stems from larval metamorphosis (Pimentel, 1960). During the adult aquatic stage the males of all four species to have a reduction in dorsal coloration, develop smooth skin, have an increase in tail length, as well as the formation of swollen vents and cornified toe pads that are used to hold onto the females during breeding (Pimentel, 1960). Breeding season differs between species, as well as within a given species; however all four species are impacted by temperature and rain when deciding to leave their terrestrial burrows and migrate to the breeding grounds (Packer, 1960). Breeding grounds tend to be slow-moving water such as ponds, lakes and sluggish sections of creeks and rivers bordered with vegetation (Pimentel, 1960). However, T. rivularis and T. sierrae prefer swift, rocky streams to that of quiet water (Hedgecock, 1978). Courtship of Taricha newts consists of the male grasping the female in amplexus, which can last up to a day before the males will dismount and deposit spermatophores that the female may pick up with her cloaca (Propper, 1991). The terrestrial adult and juvenile life stages are spent in woodlands or forests under logs, rocks and leaf debris close to the breeding ground (Pimentel, 1960). Land existence is mostly subterranean quiescence; however, T. torosa tend to spend more active time on land (Pimentel, 1960). All species of Taricha exhibit homing behavior during breeding migration, allowing the newts to return to the same habitat in which they were spawned (Hedgecock, 1978). There are few predators Taricha newts worry about while moving about either on land or in water (Johnson, 1975). To combat predation, all four species secrete a neurotoxin called tetrodotoxin (TTX) from their skin and go into a defensive posture known as “unken reflex” (Bodie, 1975). This toxin is extremely potent and indigenous people would even use the toxin to make poisons (Speak, 1923). Nowadays, species of genus Taricha are commonly sold in pet stores for $15-30.
Hedgecock, D. 1978. Population Subdivision and Genetic Divergence in the Red-Bellied Newt,Taricha rivularis. Evolution 32:271-286.
Johnson, J. A., E. D. Brodie, Jr. 1975. The Selective Advantage of the Defensive Posture of the Newt, Taricha granulosa. American Midland Naturalist 93:139-148.
Kuchta, S. R. 2007. Contact Zones and Species Limits: Hybridization Between Lineages of the California Newt, Taricha Torosa, in the Southern Sierra Nevada. Herpetologica 63:332-350.
Livezey, R. L., and G. A. Wyllie. 1961. Morphological Variation Between Local Populations of Taricha granulosa in Oregon. American Midland Naturalist 66:410-416.
Packer, W. C. 1960. Bioclimatic Influences on the Breeding Migration of Taricha rivularis. Ecology 41:509-517.
Pimentel, R. A. 1960. Inter- and Intrahabitat Movement of the Rough-Skinned Newt, Taricha torosa granulosa. American Midland Naturalist 63:470-496.
Propper, A. R. 1991. Courtship in the rough-skinned newt Taricha granulosa. Animal Behavior 41:547-554
Speak, F. G. 1923. Reptile Lore of the Northern Indians. The Journal of American Folklore 36:273-280.
Weisrock, D.W., T. J. Papenfuss, J. R. Macey, S. N. Litvinchuk, R. Polymeni, I. H. Ugurtas, E. Zhao, H. Jowkar and A. Larson. 2006. A molecular assessment of phylogenetic relationships and lineage accumulation rates within the family Salamandridae (Amphibia, Caudata). Molecular Phylogenetics and Evolution 41:368-83.