Systematics: Originally described by Carolus Linnaeus as Lacerta fasciata in 1758, based on an illustration in Catesby (1731-1743). Type locality was said to be "Carolina." Schmidt (1953) restricted the type locality to Charleston, South Carolina. Cope (1875) was the first author to use the genus Eumeces for this species. Eumeces fasciatus has been used by most authors in the Virginia literature. However, Dunn (1918, 1920) and Fowler (1925) used Pleistiodon fasciatus for this species, apparently following Brown (1908), who wrongly concluded that Eumeces was its junior synonym (Taylor, 1935). Taxonomy for Plestiodon (often as Eumeces) follows Taylor (1935, Univ. Kansas Sci. Bull. 23: 1–643) and Brandley et al. (2012, Zool. Jo. Linn. Soc. 165: 163–189), Howes et al. (2006, Mol. Phylogenet. Evol. 40: 183–194) and Richmond (2006, Evol. Dev. 8: 477–490) presented mitochondrial and nuclear DNA evidence of substantial phylogeographic structure within P. fasciatus. Although neither set of authors drew any taxonomic conclusions from their results, those results suggest the possibility of one or more cryptic species; in particular, samples from the eastern Carolinas are highly divergent in both mtDNA and microsatellites from nearby populations. No subspecies are recognized.

Description: A moderate-sized skink reaching a maximum known snout-vent length (SVL) of 86 mm (3.4 inches) and a maximum total length of 215 mm (8.5 inches) (Conant and Collins, 1991). In Virginia, maximum known SVL is 77 mm (3.0 inches) and maximum total length is 188 mm (7.4 inches). Tail length in the Virginia sample was 52.0-68.9% (ave. = 60.7 ± 2.9, n = 80) of total length.

Scutellation: Body scales smooth, overlapping, and glossy; scale rows around midbody 26-33 (ave. = 29.4 ± 1.4, n = 77); scale rows around tail 10 scales posterior to anal opening 12-19 (ave. = 15.2 ± 1.5, n = 72); subcaudal scales along midline wider than long, compared to adjacent scales; supralabials 7/7 (69.1%, n = 81), 7/8 (17.3%), or 8/8 (13.6%); posterior labial and temporal scales usuanterior to ear opening; labial scales between rostral and first supralabial entering eye (= preorbital supralabials) usually 4/4 (82.3%, n = 249), but 4/5 (13.3%) and 5/5 (4.4%) occur; postnasals present; mental single; postmentals 2.

Coloration and Pattern: Five narrow, white to cream stripes on dark-brown to brownish-gray background; light stripes and dark fields between them extend about halfway onto unbroken tails; middorsal stripe usually forks behind head, and branches reunite again on rostrum; dorsolateral stripes originate above eyes and extend posteriorly along scale rows 3-4 (counting from middorsal line; stripe involves all of 3d and part of 4th rows); lateral stripes begin below eye, and pass through ear opening and above insertion of the forelimbs and hind limbs; below this line, dorsal ground color fades into color of venter; dorsal stripes fade in large adult males such that some individuals are patternless olive to olive-brown; chin and anterior venter cream, which fades into a bluish gray posteriorly; venter of tail may be cream-colored; original tail brownish to gray; regenerated tail brownish or grayish.

Sexual Dimorphism: Adult males were similar in average SVL (64.4 ± 6.2 mm, 52-77, n = 66) to adult females (63.4 ±4.2 mm, 57-72, n = 85). Sexual dimorphism index was -0.02. Complete tail length relative to total length was nearly identical in Virginia samples (males 57.3-64.4%, ave. = 61.5 ± 2.1, n = 17; females 55.7-64.4%, ave. = 61.3 ± 2.1, n = 21), although Davis (1968) reported that males had proportionally longer tails. Adult males in the Virginia sample had larger (wider) heads (7.8-14.9 mm, ave. = 11.2 ± 1.7, n = 56) than adult females (7.3-11.2 mm, ave. = 9.5 ± 0.7, n = 79). Vitt and Cooper (1986a) demonstrated for this species in South Carolina that sexual dimorphism in head size remained significant after the variation in body size was removed. There were no sexual differences in number of scales around midbody (males 27-33, ave. = 29.6, n = 25) or number of scales around tail 10 scales posterior to the anal plate (males 12-19, ave. = 15.4 ± 1.6, n = 23; females 12-17, ave. = 15.2 ± 1.4, n = 24). Adult males lose the striping with age and old males are uniformly olive-brown to olive. During the mating season, the head turns orange to red on males. Females retain the stripes for life.

Juveniles: Juveniles possess the characteristic 5 stripes on a black background and adult scutellation. They differ from adults in having a bright blue tail, especially on the distal half, and the darker body color. The blue coloration does not extend anteriorly beyond the position of the vent. Tail color changes to gray or gray-brown when maturity is reached, about 52 mm SVL. The function of the blue tail is discussed under "Biology." At hatching, juveniles averaged 26.1 ± 2.0 mm SVL (22.0-29.7 mm, n = 48), 60.0 ± 5.6 mm total length (50.0-63.1, n = 5), and 0.35 ± 0.10 g body mass (0.22-0.38, based on means of six litters).

Confusing Species: Plestiodon fasciatus is often confused with P. inexpectatus and P. laticeps. The mid-ventral row of subcaudal scales of the former is similar in size to the other scales on the tail, and the dorsolateral light stripes occur on scale rows 4-5. Adults of the latter are very large, over 80 mm SVL; the blue tail fades to adult gray-brown at about 80 mm SVL; and there are usually no enlarged scales between the posteriormost upper labial scale and the ear opening.

Geographic Variation: Geographic variation in scutellation and pattern is not evident in Virginia samples. Davis (1968) determined that several scale characters varied independently over large geographic regions, but he did not evaluate the patterns in detail.

Biology: Plestiodon fasciatus inhabits a wide variety of habitats in the eastern deciduous and southeastern evergreen forests. It has been found in mature hardwood forest, bottomland forest, second-growth hardwood forest, mixed hardwood-pine forest, dry pine woods, cypress swamp forest, and urban wood lots; on the edges of woods and fields; and around artificial structures in woods and fields. It is occasionally seen on urban and suburban buildings. This skink is often found under surface objects, such as boards, logs, and debris, although usually among them rather than on the ground. This species prefers more moist habitats than the other species in this genus. Plestiodon fasciatus is absent from dune-grassland habitats and from forested habitats in high elevations. Five-Lined Skinks are often found in terrestrial microhabitats but arboreality is commonplace, especially in open woodlands with standing dead trees. The activity period starts in March or April, depending on the weather, and extends through October. Individuals can be found throughout the winter on exceptionally warm days. Juveniles emerge from hibernation earlier and enter it later than adults. Hibernation is known to take place deep in cracks in walls and in the decaying centers of large logs and stumps.

Plestiodon fasciatus is completely carnivorous, feeding mostly on arthropods. The prey of this skink has not been studied in Virginia. McCauley (1939) recorded the following prey types for a Maryland sample: grasshoppers, crickets, cockroaches, leafhoppers, snout beetles, long-horned beetles, click beetles, rove beetles, ground beetles, beetle larvae, flies, butterfly adults and larvae, ants, dragonflies, bristletails, spiders, sow-bugs, and pulmonate snails. Cannibalism is known to occur, mostly of adults on juveniles (Mitchell, 1986). The only recorded predators of Virginia Five-Lined Skinks are Cornsnakes (Pantherophis guttatus) (Uhler et al., 1939) and domestic cats (Mitchell and Beck, 1992), but Black Racers (Coluber constrictor), Milk Snakes (Lampropeltis triangulum), Scarlet Kingsnake (Lampropeltis elapsoides), and various predatory birds probably also prey on this lizard. Mount (1981) found that some mortality of this species in Alabama was attributable to the introduced fire ant (Solenopsis invicta), particularly in populations inhabiting xeric habitats. Fire ants have been recently introduced into several places in Virginia (W. H. Mitchell, pers. comm.) and pose an unknown threat to this species.

Females are oviparous and lay one clutch of eggs, in decaying logs and stumps lying on or above the ground, in June and early July. I have no evidence for multiple clutches. The smallest mature male was 52 mm SVL and the smallest mature female was 57 mm SVL. In South Carolina, skinks reached sexual maturity at about the same size (52 mm SVL) during their second spring after hatching (Vitt and Cooper, 1986a), Mating dates are unknown in Virginia, but Fitch (1954) noted that peak mating activity occurred in the second week in May in Kansas. Females in Virginia contained oviductal eggs between 12 and 24 June. Average clutch size was 9.3 ± 2.2 (6-14, n = 23). Clutch size for eight females from Fairfax County was 5-13 (ave. = 7.3) (C. H. Ernst, pers. comm.). Females stay with the eggs in the nest until hatching, although there is no parental care afterwards. Females may eat one or more of the eggs during brooding (J. C. Mitchell, pers. obs.; Vitt and Cooper, 1986a). Several females may nest in the same log or stump. On 5 July 1988 a communal nest was discovered in a decomposing log containing a female P. fasciatus and a female P. laticeps. The eggs of each species were within several centimeters of each other. Females attending nests have been found between 16 June and 26 July. Eggs measured soon after laying averaged 12.7 ± 1.1 x 9.1 ± 0.9 mm in size (length 10.8-14.5, width 7.0-10.5, n = 66) and weighed 0.47-0.81 g (ave. = 0.69 ± 0.14, based on means of five clutches). Eggs from a female collected in York County weighed 0.285-0.380 g (ave. = 0.326 ± 0.035, n = 5) within 30 minutes of laying (G. R. Brooks, pers. comm.). Incubation time for one clutch was 32 days, and another at 30°C was 22 days (C. A. Pague, pers. comm.). Hatching dates were between 8 July and 4 August. The earliest date for the natural appearance of a hatchling is 8 July in New Kent County (N. D. Richmond, pers. comm.).

Population size varies depending on the quality and size of the habitat. Fitch and von Achen (1977) noted that the home range of this lizard was subject to constant revision and was best described as a succession of hiding places defined by the characteristics of the specific habitat. They also found that adult males were active over a larger average distance (radius) from an activity center (18.3 m) than females (12.2 m) and juveniles (6.5 m). The population ecology of this species is unknown in Virginia.

Escape behavior involves hiding under surface objects and in crevices. These skinks do not hesitate to enter water and will sometimes escape by hiding beneath an underwater object (Fitch, 1954). Adult males frequently fight with con-specific males during the breeding season, and males locate females by following scent trails (Fitch, 1954). Male aggressive behavior is initially visual and consists of pointing the snout downward and tilting the head to one side so that the widest part is visible to the opponent. If one of the lizards does not flee, the visual displays are followed by mutual tongue-flicking to pick up chemical cues to determine the species and sex of the opponent. Males perform actual combat by biting each other on the head and throwing opponents through the air (Fitch, 1954; Cooper and Vitt, 1987a).

The function of the blue tail in this species has been studied by Cooper and Vitt (1985) and Vitt and Cooper (1986c). The blue tail of juveniles is an antipredator adaptation that serves to attract the predator away from the vulnerable part of the lizard, its body. Juveniles escape potential predators by disappearing into the leaf litter, lashing their tails back and forth above the leaves. The blue tail, contrasting with the brown background, attracts predators (birds and small, lizard-eating snakes) to the less vulnerable appendage. Once broken off, the tail twitches for a period of time, distracting the potential predator further. This increases the probability that a juvenile will survive to maturity. At onset of sexual maturity the tail color changes from blue to a cryptic gray-brown. This change occurs at a time when energy requirements for tail regeneration are also important to the growth and reproductive output of the adult (Vitt and Cooper, 1986c). Tail loss at this time decreases a female's ability to produce and brood eggs and a male's ability to win aggressive bouts with other males (and presumably to reproduce with the females in his area).

Remarks: Other common names in Virginia are scorpion or "scarapin" (Hay, 1902; Dunn, 1915a, 1918); common scorpion lizard (Dunn, 1936); and blue-tailed skink and five-lined lizard (Carroll, 1950).

Mark Catesby (1731-1743), who probably saw many of these lizards during his stay in Virginia during 1712-1719, described it as follows: "This Lizard is usually small, seldom exceeding six inches in length, the head short, the tail is blue, the rest of the body brown; except that from the nose runs five yellow lines of equal distances, along the back to the tail. They are seen often on the ground, and frequent hollow trees. Some people suspect them to be venomous, tho' I never heard of an instance to confirm it. They are found in Virginia and Carolina."

Based on similarities in shared enzymes, Murphy et al. (1983) postulated that P. fasciatus is more closely related to P. laticeps than to P. inexpectatus, and that these three species form a monophyletic group with the former two species sharing the most recent common ancestor.

U.S. Range