|Common Name:||Northern Mole Snake|
|Scientific Name:||Lampropeltis calligaster rhombomaculata|
|Genus:||Lampropeltis is derived from the Greek words lampros which means "radiant" and pelta meaning "small shields".|
|Species:||calligaster is derived from the Greek words kallimos which means "beautiful" and gaster meaning "stomach".|
|Subspecies:||rhombomaculata is derived from the Latin words rhombus which refers to the shape of the rhomboid-shaped dorsal blotches and macla which means "spots".|
|Vernacular Names:||Blotched kingsnake, brown snake, ground snake, house snake, king snake, mole catcher.|
|Average Length:||30 - 40 in. (76 - 102 cm)|
|Virginia Record Length:||40.6 in. (118.8 cm)|
|Record length:||47 in. (119.4 cm)|
PHYSICAL DESCRIPTION: The adult is yellowish or olive-brown with small red- dish-brown blotches down the back, alternating with smaller blotches on the sides. Each blotch has a narrow black border. The belly is yellowish-brown with indistinct brown spots. The juvenile is similar to the adult but the blotches are dark-edged and more vivid on young snakes, becoming much more indistinct with age. They have smooth dorsal scales with 19-23 scale rows. The anal plate is undivided and loreal and preocular scales are present. They are about 8 inches at hatching and grow to nearly 4 feet with the average adult size from 2 1/2 to 3 1/2 feet *1006*. In Virginia, maximum known SVL is 1031 mm (40.6 in.) and max total length is 1188 mm (46.8 in.). Tail length/total length ratio 10.1-16.2 (avg. = 12.9+/1.4, n=69).
SCUTELLATION: Ventrals 193-212 (avg. 200.9=/-4.0, n=70); subcaudals 37-53 (avg. = 44.5+/-3.8, n=66); ventrals + subcaudals 234-255 (avg. = 245.2+/-5.1, n=62); dorsal scales smooth; scale rows usually 21 (88.6%, n=70) at midbody, 22-23 (11.4%); anal plate single; infralabials 8-8 (57.6%, n=59), 9-9 (30.5%), other combinations of 6-9 (11.9%); supralabials 7-7 (89.2%, n=65) or 7-8 (10.8%); loreal scale present; preoculars 1-1; postoculars 2-2; temporal scales usually 2+3/2+3 (77.8%, n=63), other combinations of 1-4 (22.2%).
COLORATION and PATTERN: dorsal color of body, head and tail tan to dark brown, a yellowish tinge may be present; dorsum with a series of 35-54 (avg. = 44.3+/-4.0, n=61) chestnut brown to tan blotches that are wider (about 11 scales) than long (1-2 scales); blotches are well separated and narrowly bordered in black in juveniles and young adults; blotches are bordered by brown in old adults, if at all. Blotches fade with age and old individuals may be uniformly brown. Some individuals possess a series of small, alternating, brown or tan blotches on each side; venter cream to yellowish with varying amounts of faded brown smudges; chin and labial scales peppered black in some snakes and scales of head bordered by dark brown pigment; short, brown, eye-jaw stripe may be present - it does not extend beyond the upper margin of the supralabials; yellow pigment fades to cream in preservative. This is a cylindrical snake with a small head that is not distinct from the neck.*10760*
SEXUAL DIMORPHISM: Sexual dimorphism is shown in body proportions and scutellation. Adult males SVL (660-1031, avg. = 840.6+/-102.9, n=31) averages larger than adult females (672-984, avg. = 799.6+/-97.4, n=15) and reach larger total lengths (to 1188 mm) than females (to 1101). Sexual dimorphism index is - 1.05. Females have a lower average tail length/total length raio (10.1-14.5, avg. = 12.1+/-1.3, n=24) than males (10.7-16.2, avg = 13.4+/-1.2, n=40). Subcaudal scale counts average higher in males 40-53 (avg. = 46.6+/2.7, n=38) than in females (37-49, avg. = 41.4+/-2.7, n=23). Juveniles: Juveniles and hatchlings possess a series of chestnut brown dorsal blotches that are bordered by black. Each has a dark brown, checkerboard pattern on the cream to yellow venter, a short, reddish, eye-jaw stripe that does not pass beyond the upper margin of the supralabial scale, and 2 longitudinal chestnut to brown stripes on the back of the head. These patterns fade with age. Hatchling SVL in Va. is 170-235 mm, total length is 200-236 mm, and mass is 2.7-6.5 g.*10760*
CONFUSING SPECIES: This snake may be confused with Elaphe guttata and Lampropeltis triangulum, especially with the high elevation forms of the latter. Adults of these 2 species have larger, distinctly black bordered and fewer dorsal body blotches, and exhibit distinct ventral, black and white, checkerboard patterns. Juveniles of these species are patterned as adults and possess eye-jaw stripes that pass to or beyond the margin of the mouth. Mole kingsnakes are sometimes misidentified as copperheads (Agkistrodon contortrix). However, copperheads have brown hourglass crossbands and heads that are distinctly wider than the neck*10760* Geographic Variation: Avg. number of ventral + subcaudal scales varies from low counts in the northern Blue Ridge Mountains (239.0+/-5.0, 234-244, n=3) to intermediate counts in the upper Piedmont (248.2+/-4.3, 43-255, n=10). This character in the lower and upper Coastal Plain averages 242.6+/-4.5 (238-253, n=9). Other scale characters show no apparent geographic variation. The avg. number of body blotches in the upper Piedmont (44.3+/-3.8, 35-54, n=38) and upper Coastal Plain (45.3+/2.8, 41-48, n=7) is intermediate between those in the northern Blue Ridge Mountains (40.8+/-2.6, 37-43,n=4) and the southern Coastal Plain (49-51,n=2).*10760*
REPRODUCTION: The females are oviparous and deposit about 10 or 12 eggs. The eggs adhere to each other in clusters and hatch in the late summer *1006*. Mating probably takes place in spring and fall, although no records have been recorded in the literature. Eggs from a clutch of 15 averaged 27.8 x 21.1 mm (length 25.3-33.3, width 17.4-23.2) and from another clutch of 13 averaged 31 x 20 mm (length 28-34, width 19-20).*10760*
BEHAVIOR: This species is subterranean and nocturnal. They are usually seen when they are plowed up or at night when they are crossing a road. They are often seen on the surface of the ground in the daytime in coastal Virginia. They prowl mole tunnels in search of mice as well as moles. They also burrow on their own. The young are very active in defense and will coil and strike so vigorously that they nearly jump off the ground. This species will feed on mice, snakes and lizards as the prefered foods, but will also take moles and shrews, small frogs and toads. Like other kingsnakes, this species is a constrictor *1006*.
LIMITING FACTORS: The maximum age for this species is 14 years, 7 months *11523*.
AQUATIC/TERRESTRIAL ASSOCIATIONS: Natural enemies include racoons, opossums and skunks *1006*. Another documented predator is the eastern kingsnake *11523,11506*. The population ecology of this snake has been studied only in Kansas. A total of 166 mole kingsnakes were found in a 30 year study, yielding an estimated density of 0.55 per hectare. Clifford recorded 10 more kingsnakes of a total of 278 in a 4 year period in Amelia Co. The rarity of this snake is due to its secretive behavior; it may be more abundant than we are aware.*10760*
References for Life History
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|Prince William Co.||Fairfax Co.||Fairfax Co.|