Plethodon

Temporal alterations in peripheral chemoreceptors are rare in vertebrates, but this group provides an example of transient enhancement of signal capture efficiency. The Red-backed salamander (Plethodon cinereus) shows dimorphic and seasonal VNO volume fluctuations. Males always possess a significantly larger vomeronasal area, and both... 

Fig. 20.4 Comparison of secreted proteins in pheromone extracted (A) from mental glands of Desmognathus ocoee (which has non-olfactory pheromone delivery) with (B) pheromone extracted from Plethodon shermani (which has olfactory delivery). Lanes 1 and 3 are MW standards. SDS-PAGE (15% Tris-Tricine)... 

Highton, R. and Peabody, R.B. (2000) Geographic protein variation and speciation in salamanders of the Plethodon jordani and Plethodon glutinosus complexes in the southern Appalachian Mountains with the descriptions of four new species. In R.C. Bruce, R.G. laeger, and L.D. Houck. (Eds.) The biology of plethodontid salamanders. Plenum, New York, pp. 31-94. 

Houck, L.D., Bell, A.M., Reagan-Wallin, N.L. and Feldhoff, R.C. (1998) Effects of experimental delivery of male courtship pheromones on the timing of courtship in a terrestrial salamander, Plethodon jordani (Caudata Plethodontidae). Copeia 1998, 214-219. 

Larson, A. and Highton, R. (1978) Geographic protein variation and divergence of the salamanders in the Plethodon welleri group (Amphibia Plethodontidae). Syst. Zool. 27, 431 —448. 

There are sex differences in woodland salamanders Plethodon) and brook salamanders (genus Burycea) of the lungless salamander family Plethodontidae, females have smaller VNOs than males (Dawley, 1992). There are also species differences the VNO in Burycea wilderea is larger than that in Plethodon cinereus, and the size of the hypertrophied nasal grooves, called cirri, correlate with size of VNO (Dawley, 1992). 

Male red-backed salamanders Plethodon cinereus) in Petri dishes were given a choice between own feces and those of another male. They preferred their own. The same was true for washes from the cloacal glands (Simon and Madison, 1984). While this may represent discrimination of own and other, rather than true individual recognition, another experiment showed... 

Courtship pheromones are not necessarily species specific. Pairs of the woodland salamander, Plethodon shermani, courted for an equally long time (about 35 to 50 minutes) whether male pheromone from the mental gland of conspecifics or the allopatric species P. montanus or P. yonahlosscc was present, even though the composition of the proteinacous pheromones (plethodontid receptivity factor of these three species differ considerably (Rollmann et al, 2003). 

Another salamander courtship pheromone, identified in 1999, is a protein. During courtship, males of the Appalachian woodland salamander, Plethodon jordani, (Plethodontidae), a terrestrial species, actively deliver a pheromone to the female. In the mating season, males develop a mental gland, located... 

A non-toxic species of salamander may derive protection from predators by visually resembling a toxic form so closely that predators cannot distinguish between them Batesian mimicry). Free-ranging birds avoid both the toxic red eft Notophthalmus viridescens) and the similar-looking non-toxic red morph of the red-backed salamander Plethodon cinereus). The red-striped morph of P. cinereus, which does not resemble the red eft, is eaten (Brodie and Brodie, 1980). 

Salamander Plethodon richmondi Ringneck snake Diadophis punctata Traces on substrate Avoidance Cupp, 1988... 

On land, snakes prey on salamanders and their eggs. The ringneck snake Diadophis punctata) and its prey, the salamanders Plethodon richmondi and Plethodon dorsalis provide an example. Salamanders were given a choice between a paper towel that had had a ringneck snake on it for 48 hours, and one with clean water. The salamanders of both species avoided the substrate with the odor of the ringneck snake (Cupp, 1988). 

Tristram, D. A. (1977). Intraspecific olfactory communication in the terrestrial salamander Plethodon cinereus). Copeia 597-600. 

Woodland and slimy (Plethodon) salamanders are lung-less and lack an aquatic phase, reproducing in moist regions of the forest. They have evolved to employ large peptide contact pheromones, which are best understood in the Jordan s salamander and partially described in the Ocoee salamander.71... 

To test their ability to discriminate individuals, male and female salamanders (in the US several species of the genus Plethodon) are given a choice of odors in a Y-maze. The odors tested can be male vs. female mate vs. strange individual of opposite sex individuals from different populations or closely related species (Dawley 1985). 

Field-collected red-backed salamanders (Plethodon cinereus) were exposed to 2,4-DNT in soil for 28 d [66]. A sandy loam soil was characterized and spiked with 2,4-DNT at concentrations of 0, 75, 200, 800, and 1500 mg kg 1 dry weight (dw) soil. Food consisted of adult mutant fruit flies (Drosophila melanogaster flightless) that were not exposed to DNT. All animals exposed to analytical concentrations greater than 1000 mg DNT kg-1 and not soil died within the first week of exposure. 

Johnson MS et al., Toxicological responses of red-backed salamanders Plethodon cinereus) to subchronic soil exposures of 2,4-dinitrotoluene. Environ. Pollut. 147, 604, 2007. 

Johnson MS et al., Toxicologic and histologic response of the terrestrial salamander Plethodon cinereus to soil exposures of l,3,5-trinitrohexahydro-l,3,5-triazine, Arch. Environ. Contam. Toxicol., 47, 496, 2004. 

Peptides from the skin of the red-backed salamander (Plethodon cinereus) killed 90% of a culture of staphyolococci within 2 h. Peptides may be leads to design and synthesize compounds that act as novel antibiotics. 

Amphibian pheromones have been previously isolated fh>m newt and salamander species, however, this peptide, which we have named splendipherin, is the first pheromone isolated fiom any anuran species. The delivery method of those previously isolated amphibian species are very clear. Sodefiin, the ten-residue peptide pheromone of Cynops pyrrhogaster and silefiin, the ten residue peptide pheromone of Cynops ensicauda are both sent through the water by the male newts by a vigorous shaking movement of the tail (Kikuyama et al., 1995 Yamamoto et al., 2000). The 20 kDa proteinaceous male courtship pheromone of Plethodon jordani is applied to the female s sldn by direct contact (Rollman et al., 1999). 

Sexual isolation has arisen among numerous species of geographically isolated populations of salamanders (review by Arnold et al., 1993). Behavioral experiments indicate that the degree of reproductive isolation is stronger between sympatric species of large Plethodon than it is between allopatric populations of these species (Reagan, 1992). Sexual isolation may be due to species-specific differences in the chemosensory systems... 

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