Observations on Reproduction in the Southern Coal Skink (Eumeces anthracinus pluvialis Cope)

Abstract

Little is known of the reproductive potential of the southern coal skink (Eumeaes anthracinus pluvialis), an egg-laying lizard that ranges erratically from western North Carolina southwest to Louisiana and thence northwest to eastern Kansas. Gloyd (1928) collected a female of this species on 3 May 1926 in Franklin County, Kansas, which laid eight eggs between 21 and 23 June. The eggs averaged 6 x 10 mm in size, and six hatched between 24 and 25 July, an incubation period of slightly oorer one month. Taylor (1935) noted this Kansas clutch, but added no additional observations on reproduction in this lizard. Smith and Smith (1952) recorded a female southern coal skink from Oregon County, Missouri, which laid eight eggs (no dategiven) thatranged from 7.0 to 7. 8 mm in width and 12 to 1 3 mm in length at deposition. The eggs increased in sizeathatchingto 11 to 12mminwidthand 16.2 to 18mminlength. Anderson (1965) noted the Oregon County clutch and recorded a female from Camden County, Missouri, which laid eight eggs on 27 May. The eggs averaged 7.5 x 12.5 mm in size. Fitch (1970), in summarizing reproduction in lizards and snakes, did not include an account on Eumeres anthraainus, presumably due to paucity of information about this species. Thus, only three known clutches of eggs have been recorded for Eumeres anthracinus plutZialis, all numbering eight eggs per clutch. On 14 April 1974, a female southern coal skink (University of Kansas, Museum of Natural History-KU 154997) with a snout-vent length of 65.5 mm and a total length of 154.5 mm was collected by Diana Weigmann at Baldwin Woods, Douglas County, Kansas. This specimen was maintained in capacity and laid eleven prolate eggs (KU 154998) on 19 May 1974. The eggs ranged in size from 6.8 to 7.4 mm (SD =0. 14, x= 7.02) in width and 10.8 to 1 1.2 mm (SD=0. 14, x= 10. 76) in length. According to RandallJohnson (who maintained the lizard in captivity), the female exhibited protective behavior. When the eggs and nest were disturbed, the female would curl on top of the eggs. Johnson did not observe aggressive behavior, but another lizard (Leiolopisma laterale) maintained in the same cage was killed by the female. In summary, this clutch is the fourth reported for Eumeces anthrarinus pluvialis. Known dates of egg deposition for three clutches were during May,