Megapallifera mutabilis (Hubricht, 1951)
External: Light brown body with brown flecks and dark gray-brown spots; sometimes with a double, longitudinal broken line of dark brown along the mid-dorsum; vague brown chevrons crossing the mid-dorsum; grayish brown, irregular bands on the lower sides with a distinct upper edge and a fading lower edge; brown or olive-gray foot edges and tail tip; yellow-cream, opaque sole (Webb 1950; Hubricht 1951; Burch 1962)
Internal: Jaw with 5-8 ribs; penis containing 5-7 pustulose longitudinal pilasters (ridges) that extend between the apical chamber and the penis mid-point, and irregularly pustulose thereafter; very wide basal spermatheca duct with seven simple longitudinal ridges inside; atrium with cream glandular tissue around its lower section; two lobes, each with 2-3 folds dividing it, inside upper atrium (Hubricht 1951; Fairbanks 1990).
Similar to P. carolinianus but with brownish foot edge and ribbed jaw (Webb 1950), and no orange granules in sole (MEP). M. wetherbyi differs with chevron bands on dorsum and no side bands (Hubricht 1951).
Juveniles: dark gray band on each side and dorsum, with diagonal stripes connecting them (Hubricht 1951), although they may not be distinguishable from juveniles of other Megapallifera and Philomycus (MEP).
60-100 mm long (Burch 1962); extended: 100 m long or more; preserved: 62 mm long (Hubricht 1951).
SE USA (New York S to Georgia and Louisiana, W to Texas, Missouri, and Illinois) (Burch 1962; Hubricht 1985); to S Ontario (Grimm 1996).
Old-growth deciduous forest (Fairbanks 1990) as well as sometimes urban areas (Hubricht 1985) and sandstone outcrops (Webb 1950); usually upland (Hubricht 1985); "trunks of smooth-barked trees at night and in wet weather" and "lawns, old shade trees," and tombstones in urban areas (Hubricht 1985); under bark of dead trees (Fairbanks 1990).
Usually or entirely outcrosses rather than self-fertilizes (in the populations studied) (Anderson & McCracken 1986).
Feeds mainly on algae that grow on tree trunks and other surfaces.