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Two-lined SalamanderEurycea bislineata |
Physical Description Geographic Range Diet Reproductive Behavior Habitat Taxonomic History Conservation Specimens Links Reference
Adult Northern two-lined salamanders can range in size from 6.4 to 12.1 cm in length. They are characterized by a broad stripe that extends the length of their body. The stripe, bordered on both sides by narrow black lines, ranges in color from yellow to greenish yellow to tan. The middle of the stripe may be marked with a row of dark spots. Yellow or mottled pigmentation goes down the sides and small legs to the yellow belly. Sexual dimorphism exists among males and females, but is more pronounced in the breeding season. During breeding, males have several different characteristics. They have whitish lower eyelid glands, a distinctive mental gland on their chin and cirri (protruding extensions of the naso-labial gooves). Young and older larvae differ from adults in coloration and markings. Young larvae are yellowish in color with gray or brown spots on thier back and head. They also possess one dark irregular stripe containing six to nine light spots along the upper regions of each side. A secondary row of spots may develop as the larvae age. The larvae also have short distinctive, reddish brown gills (Harding 1997).
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Geographic RangeThe range of E. bislineata extends south from southern Quebec and New Brunswick to northern Virginia, and west from New England to northeastern Ohio (Harding 1997).
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The two-lined salamander is mainly insectivorous. Adults consume a wide variety of insects including beetles, mayflies, springtails, spiders and centipedes. Adults may also consume other small invertebrates such as earthworms and snails. The larvae have an entirely different diet which consists of aquatic larvae of mosquitos, caddisflys, stoneflys, and beetles. The main nutrition for larvae comes from crustaceans and copepods (Harding 1997). The larvae maintain a very varied diet as they mature, continuing to ingest large amounts of small prey even after the developmental point when their jaw size is large enough to consume larger prey (Petranka 1984).
E. bislineata reaches sexual maturity the first fall, or occassionally, one year after metamorphosis. The two-lined salamander uses internal fertilization. The female collects a spermatophore in her cloaca and fertilization occurs. The breeding season is from October to May with eggs usually being laid in April or May. The egg clutch may contain as few as fifteen or as many as a hundred eggs. The eggs are attached toa firm substrate, such as a rock, in a flowing stream or spring (Harding 1997). Recently, it has been found that females attach their eggs to vegetational carpets in fish free, acidic lakes (Bahret 1996). The incubation period for the eggs is thirty to sixty days with the female guarding the nest for at least part of that period. Larvae range in size from 1.2-1.4 cm snout to tail when they hatch. After two to three years as aquatic larvae, the larvae metamorphose into semiterrestrial juveniles. Parental care stops after the eggs hatch (Harding 1997). Two-lined salamanders exhibit complex courtship behavior. The male uses his head to nudge a potential mate, and encircles the female's head with the front of his body. The male scratches the female's skin with his teeth to possibly allow secretions from his mental glands to reach her bloodstream. It has been suggested that the secretions stimulate courtship behavior in the female. If the female accepts the male, the two engage in a "tail straddling" walk where the male releases a spermatophore that is picked up by the female (Harding 1997).
Adult salamanders prefer the cover provided by logs, rocks or fallen leaves which often is found in woodland habitats. The salamanders are often found along stream banks, but can be found as far as a few meters from a water source. During the winter, the adult two-lined salamander may remain active in streams or springs where temperatures permit or they may burrow deep into leaf litter, becoming inactive during cold seasons. Larvae are typically found in flowing waters of streams or springs (Harding 1997). However, in at least one region of their range, larvae have been found in lakes (Bahret 1996).
Salamandra bislineata Green, 1817, J. Acad. Nat. Sci. Philadelphia, (1)1: 352.
Syntypes: ANSP 695-698 (according to Fowler and Dunn, 1917, Proc. Acad. Nat. Sci.
Philadelphia, 69: 20) and/or USNM 3738; see Mittleman, 1966, Cat. Am. Amph. Rept.,
45.1, for discussion. Type locality: Not stated; subsequently designated as "New Jersey
(probably Princeton?)" by Fowler, 1906, Ann. Rep. New Jersey State Mus., Pt.2: 65.
S[alamandra]. flavissima Harlan, 1826, Am. J. Sci., 10: 286. Holotype: "a specimen in
the cabinet of the Acad. of Nat. Sc. of Phil." Not now extant in the ANSP. Type locality:
"Pennsylvania", USA; restricted by Schmidt, 1953 to vicinity of Philadelphia. Synonymy
(withe Spelerpes bis-lineata) by Harlan, 1835, Med. Phys. Res.: 97; (with Spelerpes
bilineata [sic]) Gray, 1850, Cat. Spec. Amph. Coll. Brit. Mus., Batr. Grad.: 44.
Synonymy by Duméril, Bibron, and Duméril, 1854, Erp. Gén., 9: 91.
Salamandra bitaeniata Valenciennes In Duméril, Bibron, and Duméril, 1854, Erp. Gén.,
9: 63. Nomen nudum. Synonymy by Duméril, Bibron, and Duméril, 1854, Erp. Gén., 9:
63.
Pseudotriton bilineata--Tschudi, 1838, Classif. Batr.: 60. Misspelling.
Mycetoglossus bilineata--Bonaparte, 18XX, Faun. Ital., 2: 131. {source is Gray, 1850,
Cat. Spec. Amph. Coll. Brit. Mus., Batr. Grad.: 45}.
Salamandra haldemani Holbrook, 1840, N. Am. Herpetol., Ed.1, 4: 125. Holotype:
unknown; fixed by Mittleman, 1966, XXXX as plate 28 in Holbrook, 1840, N. Am.
Herpetol., Ed.1. Type locality: "from the borders of the Susquehanna River,
(Pennsylvania)", USA, restricted by Schmidt, 1953, Check List N. Am. Amph. Rept.,
Ed. 6: XXX, to Harrisburg. Synonymy by Cope, 1889, XXXXX. Folwer, 1906, Proc.
Acad. Nat. Sci. Philadelphia, 58: 357, regarded it to be a synonym of Desmognathus
fuscus.
Spelerpes bilineata--Baird, 1850 "1849", J. Acad. Nat. Sci. Philadelphia, (2)1: 287;
Gray, 1850, Cat. Spec. Amph. Coll. Brit. Mus., Batr. Grad.: 38.
Ambystoma ? haldemani--Gray, 1850, Cat. Spec. Amph. Coll. Brit. Mus., Batr. Grad.:
38.
Bolitoglossa bilineata--Duméril, Bibron, and Duméril, 1854, Erp. Gén., 9: 91.
Spelerpes haldemani--Hallowell, 1854, J. Acad. Nat. Sci. Philadelphia, (2)3: 347.
Salamandra dorsata Valenciennes In Duméril, Bibron, and Duméril, 1854, Erp. Gén., 9:
93. Type locality: designated as Harrisburg, Pennsylvania fide Schmidt, 1963. Holotype:
not designated; fixed by Mittleman, 1966, XXXX, as Figure 1, Vélin 88 du MNHN,
Paris (Duméril, Bibron, and Duméril, 1854, Erp. Gén. 9:93).
Salamandra bitaeniata Valenciennes, 1854, In Duméril, Bibron, and Duméril, Erp.
Gén., 9: 93. Holotype: None designated; fixed by Mittleman, 1966, XXXX, as Figure 5,
Vélin 88 MNHN, Paris (Duméril, Bibron, and Duméril, 1854, Erp. Gén., 9: 93). Type
locality: None designated.
Spelerpes (Cylindrosoma) bilineata--Hallowell, 1856, Proc. Acad. Nat. Sci.
Philadelphia, 8: 101.
Desmognathus haldemani--Cope, 1859, Proc. Acad. Nat. Sci. Philadelphia, 11: 124.
Spelerpes bilineatus--Verrill, 1863, Proc. Boston Soc. Nat. Hist., 9: 199.
Spelerpes bilineatus--Boulenger, 1882, Cat. Batr. Grad. Coll. Brit. Mus.: 66.
Geotriton bilineata--Garman, 1884, Bull. Essex Inst., 16: 39.
Spelerpes bilineatus borealis Baird, 1889, in Cope, Bull. U.S. Natl. Mus., 34: 165.
Syntypes: USNM 4735 (11 specimens, 9 adults and 2 larvae). Type locality: "Lake
Oquassa" (= Kennebago Lake, near Oquossoc, Franklin County, Maine).
Spelerpes bislineatus--Hay, 1892, Rept. Geol. Indiana: 448.
Eurycea bislineata--Stejneger and Barbour, 1917, Check List N. Am. Amph. Rept.,
Ed.1: 18.
Eurycea bislineata bislineata--Dunn, 1920, Proc. Biol. Soc. Washington, 33: 134.
Eurycea bislineata major Trapido and Clausen, 1938, Copeia, 1938: 118. Holotype:
USNM 104239. Type locality: "under limestone slabs along Ouiatchouan River, Val
Jalbert, Lake St. John Co[unty], Quebec", Canada. Synonymy with Eurycea bislineata
bislineata by Mittleman, 1949, Proc. Biol. Soc. Washington, 62: 89-96/
Eurycea bislineata rivicola Mittleman, 1949, Proc. Biol. Soc. Washington, 62: 93.
Holotype: USNM 129397. Type locality: "Echo Canyon, McCormick's Creek State
Park, Owen County, Indiana", USA. Distinction from Eurycea bislineata bislineata
rejected by Sever, 1972, Herpetologica, 28: 314-324.
Eurycea bislineata has gone through several name changes. Originally, the species was identified in 1817 by Green. The species has had several name changes because of its wide geographic range and confusion in the early stages of herpetology about how to classify species. In 1850, Baird renamed the species Spelerpes bilineata because of similiarities he found between the specimen in Philadelphia and one at the British Musuem of Natural History. Eventually in 1920, the species was given the name Eurycea bislineata bislineata by Dunn. Two other subspecies have since been discovered (E. bislineata major and E. bislineata rivicola), but there is controversy as to whether these are actual subspecies or just variation within E. bislineata.
Conservation
IUCN: No special status
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Academy of Natural Sciences of Philadelphia
American Museum of Natural History
Linkshttp://cmgm.stanford.edu/~meisen/herp/ American Natural History Museum
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Bahret, R. 1996. Ecology of the lake dwelling Eurycea bislineata in the Shawangunk Mountains, New York. Journal of Herpetology 30:399-401.
Harding, James H. 1997. Amphibians and Reptiles of the Great Lakes Region. University of Michigan Press, Ann Arbor, MI.
Petranka, J.W. 1984. Ontogeny of diet and feeding behavior of Eurycea bislineata larvae. Journal of Herpetology 18:48-55.
Pictures: 1)animaldiversity.ummz.umich.edu/accounts/eurycea/e._bislineata.html
Map)U.S. Geological Survey (see Links)
2)gto.ncsa.uiuc.edu/pingleto/herps/sally.html
3)www.cortland.edu/www/herp/keys/salapix.htm