Cave Frogs and Salamanders

Although many types of frogs, toads, and salamanders may wander into caves, and be classed as accidentals, there is just one type of Missouri frog, and 5 types of Missouri salamanders which use caves deliberately, and on a consistent enough basis to be considered as trogloxenes, troglophiles or troglobites. These are: the pickerel frog Rana palustris, the Southern redback salamander, Plethodon serratus, the slimy salamander, Plethodon glutinosus, the long-tailed salamander, Eurycea longicauda, the cave salamander, Eurycea lucifuga, and the grotto salamander, Typhlotritron spelaeus. There is some question whether the Southern redback in caves is just a confusion with the Ozark zigzag salamander, Plethodon dorsalis, as the outward appearances of the two are similar, and they are closely related.

The pickerel frog frequents cave entrances and stream areas year round, but they are most noticeable in the winter. Tens and sometimes hundreds of these frogs then crowd the mud banks of cave streams as this location is their favorite overwintering locale. Pickerel frogs are confused with several species of leopard frogs while outside--(they have a similar, brown, spotty appearance) but only the pickerels go caving. They stay permanently from November to March, when they leave the caves to breed in swampy areas. After staying outside during the spring and summer, they re-enter the caves in late summer. Pickerel frog's skin secretions are irritating or possibly poisonous to other small animals. Pickerel frogs are classed as either trogloxenes, or possibly troglophiles.

The Southern redback is largely a salamander of cave entrances. Since all cave using salamander species are lungless, and breathe through their skin, they require moist, damp places in which to forage and dwell. This is not a common cave salamander, at least in the Northern Ozarks. Both it and the zigzag are identifiable by a reddish strip down the back, and gray sides of the body. The redback is more prominently reddish orange, and that color covers the entire expanse of the back, whereas the zigzag red or orange stripe is never more than 1/3 the width of the back. It is probably considered a trogloxene.

Slimy salamanders are also common in caves, most notably near the entrances, although not exclusively. Slimies are easy to identify, as they are black with light colored spots, and an very slick and shiny skin. Their young hatch as miniature adults. Although considered as troglophilic, slimy salamanders are not uncommon above ground, in wet, moist areas, such as debris piles, or after a rain.

The long-tail salamander (and its subspecies cousin the dark-sided salamander,) are both common cave dwelling salamanders in the Ozark Highlands. They are usually an olive-yellow in color with darker brown splotches, or in the case of the dark-sided, dark body sides. These salamanders, along with the bright orange with dark spotted cave salamander, are probably the most common cave dwelling salamanders, found throughout damp Missouri caves. These salamanders eat small arthropods, and are quite agile, being found in all sorts of impossible positions along cave walls, ceilings and floors. The young hatch into gilled larva which live in the water for up to a year before becoming lungless adults.

Strangest of all Missouri cave salamanders are the grotto salamanders. These troglobitic creatures hatch in the water as dark larvae, with functional eyes, and gills. They grow larger as larvae than their adult size, to which they shrink as they mature. They lose their gills, and their pigment as they grow, and the eyelids fuse shut. In some specimens, the eyes appear to "sink' into the head. Eventually, the mature grotto salamander thins down. The adults continue to live in, or very near the cave stream, though they make forays away from the water if an ample food supply in a moist place is available. They are the only true troglobitic salamander in the state.