Systematics: Described originally as Coluber septemvittatus by Thomas Say in 1825, based on a specimen from "Pennsylvania." McCoy (1982) restricted the type locality to Philadelphia. The name Regina leberis (first use of combination in Baird and Girard, 1853) was long thought to pertain to this species. Baird and Girard had selected Coluber Leberis, described by Carolus Linnaeus in 1758, as the type species for their new genus, Regina. They synonymized the name proposed by Say (1825), assuming that leberis was the senior synonym. Cope (1895b) first used the combination Natrix septemvittata to indicate the close relationship of this species to water snakes. However, in his posthumously published monograph (Cope, 1900), either he or his compiler mistakenly used the scientific name Natrix leberis for this snake. In the Virginia literature, Dunn (1915a) and Hay (1902) used the name Regina leberis, following Baird and Girard (1853). Numerous subsequent authors, however, used the name Natrix septemvittata (Dunn, 1915c, 1915d, 1918, 1920; Hoffman, 1945a; Hutchison, 1956; Burger, 1958; Conant, 1958, 1975), following Cope (1895b).

Stejneger and Barbour (1917), initially, and Smith and Huheey (1960a) determined that the snake described by Linnaeus (Coluber Leberis) was actually a specimen of Storeria occipitomaculata. Smith and Huheey (1960b) recommended that the International Commission on Zoological Nomenclature (ICZN) place Regina on the Official List of Generic Names in Zoology, with the recognition of Coluber septemvittatus Say, 1825, as the type species. They also petitioned the ICZN to officially suppress Coluber leberis Linnaeus so that it could no longer be used in taxonomy. However, it was not until the publication of Rossman and Eberle (1977; see Nerodia erythrogaster account) that the confusion over the relationships of water snake (Natrix, now Nerodia) and crayfish snake (Regina) genera was reasonably settled. Subsequent authors in the Virginia literature have used Regina septemvittata (Mitchell and Pague, 1984; Mitchell and Mitchell, 1989). No subspecies are recognized.

Description: A small- to medium-sized snake reaching a maximum total length of 921 mm (36.3 inches) (Conant and Collins, 1991). In Virginia, maximum known snout-vent length (SVL) is 555 mm (21.9 inches) and maximum total length is 715 mm (28.1 inches). In the present study, tail length/total length was 20.4-34.4 (ave. = 25.4 ± 2.3, n = 55).

Scutellation: Ventrals 124-151 (ave. = 138.1 ± 4.2, n = 61); subcaudals 47-87 (ave. = 71.9 ± 8.7, n = 47); ventrals + subcaudals 183-230 (ave. = 209.0 ± 11.5, n = 47); dorsal scales keeled, scale rows 19 at midbody; anal plate divided; infralabials 10/10 (53.5%, n = 43) or other combinations of 9-11 (46.5%); supralabials 7/7 (81.0%, n = 42) or other combinations of 6-8 (19.0%); loreal scale present; preoculars 2/2; postoculars 2/2; temporal scales usually 1+2/1+2 (82.9%, n = 41), but may be other combinations of 1-3 (17.1%).

Coloration and Pattern: Dorsum of head, body, and tail uniformly dark brown with a cream-colored lateral stripe on scale rows 1 and 2 on each side; dorsal color often darker on scale rows 3-5 than above; 3 thin, very dark-brown to black stripes occur on dorsum of some specimens, especially young ones; 2 dark-brown fields present between lateral light stripes and venter; venter cream with 2 narrow, dark-brown to black stripes that break up on tail; these may be thin or occur as broad stripes leaving a narrow, cream midventral line; chin and labials white; a distinct line separates white supralabials from dark-brown dorsum of head; white lateral stripe is continuous with white on head.

Sexual Dimorphism: Adult males averaged slightly less in SVL (412.3 ± 67.1 mm, 305-522, n = 18) than females (440.9 ± 72.6 mm, 318-555, n = 27), but reached a similar maximum total length (males 712 mm; females 715 mm). Sexual dimorphism index was 0.07. Average tail length/total length in males (26.9 ± 2.1%, 23.2-34.4, n = 20) was similar to that in females (24.5 ± 1.9%, 20.4-29.9, n = 35). The average number of ventrals was similar between the sexes (males 139.7 ± 4.1,133-151, n = 24; females 137.0 ± 4.0,124-143, n = 35), but the number of subcaudals was higher in males (77.8 ± 7.0, 62-87, n = 18) than in females (68.2 ± 7.6, 47-79, n = 29). Consequently, the number of ventrals + subcaudals was higher in males (218.3 ± 8.3, 198-230, n = 18) than in females (203.2 ± 9.1,183-219, n = 29).

Confusing species: Regina septemvittata may be confused with Liodytes rigida, which lacks the lateral white stripe, but has dark oblique lines on the neck and 2 rows of half-moon-shaped spots on the venter. Individuals of Nerodia sipedon in the range of R. septemvittata have dark crossbands anteriorly and blotches on the dorsum alternating with dark blotches on the sides posteriorly. Thamnophis sauritus and T. sirtalis have a light-colored middorsal stripe.

Geographic Variation: Sample sizes are sufficiently large in three regions-upper Piedmont (UP), lower Piedmont (LP), and southern Ridge and Valley (SRV)-for geographic comparisons of scale characters. The variation in average number of ventrals was similar across regions (UP 137.2 ± 3.4, 127-143, n = 21; LP 136.0 ± 1.4, 134-137, n = 5; SRV 138.8 ± 5.1, 124-151, n = 27), as was the number of subcaudal scales (UP 72.4 ± 8.8, 55-87, n = 17; LP 70.8 ± 5.9, 66-80, n = 5; SRV 72.6 ± 7.7, 55-84, n = 17) and the number of ventrals + subcaudals (UP 209.4 ± 10.1,194-216, n = 17; LP 206.8 ± 7.0, 200-217, n = 5; SRV 211.5 ± 11.5, 193-230, n = 17).

Biology: Regina septemvittata is diurnal and inhabits shallow, rocky streams in agricultural, urban, and forested areas, often in open patches that allow sunlight to reach the substrate. Loose rocks are used for shelter, and overhanging vegetation is usually present. Queensnakes have also been found in ditches and around the edges of lakes and ponds. Activity record extremes based on museum records are 7 February (Catesbeiana V37 N1 p.56) and 10 October.

Regina septemvittata is a predator of crayfish, consuming only those that have recently shed their exoskeletons. Only crayfish have been found in Virginia specimens. Other types of prey (e.g., dragonfly naiads, small catfish, toads [Anaxyrus spp.], snails) are rarely taken (Ernst and Barbour, 1989b). Known predators of queen snakes include great blue herons (Ardea herodias) and hellbenders (Cryptobranchus alleganiensis) (Ernst and Barbour, 1989b).

Queensnakes are viviparous. The smallest mature male in the Virginia sample was 305 mm SVL and the smallest mature female was 318 mm SVL. Mating occurs in spring and fall (Branson and Baker, 1974). In Virginia, litter size was 5-13 (ave. = 9.8 ± 2.5, n = 11). Records of birth dates for Virginia females are 17-31 August.

Queensnakes are common in some streams, especially those with abundant flat rocks for shelter and a rich crayfish resource. However, R. septemvittata populations have declined in those streams that have experienced declines in crayfish. This snake is no longer abundant in Pennsylvania for this reason (McCoy, 1982). Populations in the Virginia Piedmont are at risk from siltation and damming of streams. A population that existed in Westham Creek on the University of Richmond campus up until the 1970s was extirpated by the siltation of the rocky habitat. Branson and Baker (1974) studied the ecology of a Kentucky population and found 0.18-0.26 snake per meter of stream. The ecology of this snake has not been studied in Virginia. Thermoregulation occurs in two ways: by basking in full or partial sun on the branches of overhanging vegetation, or by absorbing the heat from beneath flat rocks in full sun. Snakes found under rocks are usually lying in a pool of water. Escape behavior is to drop off overhanging branches and hide beneath cover in water or swim away. This snake seldom bites when caught, but may eject musk from glands at the base of the tail or defecate.

Remarks: Other common names in Virginia are striped water snake (Hay, 1902; Dunn, 1936; Burch, 1940); water garter snake (Carroll, 1950); and garter snake, willow snake, branch snake, leather snake, and water snake (Linzey and Clifford, 1981).

Linzey and Clifford (1981) noted that Lucy and Charlie Brown in the cartoon strip "Peanuts" maintained a fear of the "deadly Queen Snake," assuming wrongly that it was venomous.

Conservation and Management: This species does not appear to be in danger of extirpation in Virginia. However, urbanization and other forms of development are impacting some populations due to channelization, siltation, and damming of streams. Maintenance of clean, rocky streams in the Piedmont and western portions of Virginia and their crayfish populations will ensure the long-term presence of R. septemvittata in the Commonwealth.

U.S. Range