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6.1 AMPHIBIA: CAUDATA: AMBYSTOMA GRACILE The nonbreeding adult lives beneath logs, fn leaf SNYDER,RICHARDC. 1963. Ambystoma gracile. p. 6. litter, stumps, or other damp places in deciduous or In W. J. Riemer (ed.), Catalogue of American Amphib• coniferous forests; larval life is confined to ponds and ians and Reptiles. American Society of Ichthyologists lakes. Montane populations are composed primarily and Herpetologists, Bethesda, Maryland. of neotenic individuals; at lower elevations, popula• tions of neotenic may coexist in the same ponds with larvae destined to metamorphose (Snyder, Ambystoma gracile (Baird) 1956). Northwestern • FOSSILRECORD.Unknown. Sire don gracilis Baird, 1859:13. Type-locality, "Cas• • PERTINENTLITERATURE.For the important ref• cade Mountains near 44° N. latitude," []. erences see DESCRIPTIONS. Two syntypes (larvae), U.S. Natl. Mus. 4080, col• • REMARKS.The species was first described from lected by Dr. J. S. Newberry. Colleetion date un• the larval form by Baird, 1859. In 1867,Baird in Cope known; catalo~ed 2 August 1858. described the adult stage for the first time, making no Ambystoma gractle: Dunn, 1926:136. Transfer of S. association between it and the larvae described earlier. gracilis to Ambystoma. The division of the two subspecies is based on adult characters. The attempt to distinguish their larvae • CONTENT.Two subspecies are recognized: Amby• (Dunn, 1944) on the basis of belly pigmentation and lateral spotting may not be valid since these character• stomabystomagracilegracilegraciledecorticatumsouth of northlatitudeof51latitude° N. and51°Am•N. istics vary with age and sex, and possibly with alti• The subspecies are not well differentiated (see Dunn, tude in (Snyder, 1956). 1944,for discussion). • ETYMOLOGY.The name gracile signifies "slender" • DEFINITION.Adults are dark blackish brown above, or "delicate" from the Latin gracilis. The name lighter brown below. Parotoid glands are prominent decorticatum signifies "like bark" from the Latin de and often lighter colored (lighter brown or tan) than "from" and cortex "bark or cork." the head. A glandular ridge is present along the top of the tail; the tail is rounded above and sharply I. Ambystoma gracile gracile (Baird) edged below. Costal grooves are typically 11. Small irregular whitish or yellowish spots and blotches occur Siredon gracilis Baird. See species account. on the dorsum (A. g. decorticatum) or are lacking (A. Ambystoma gracile: Dunn. See species account. g. gracile). Individuals are commonly neotenic, par• ticularly at high altitudes. Average size of full grown AmblystomaAmbystoma gracileparoticumgracile:BairdDunn,in Cope,1944:1867:200.130. First individuals is 80-90 mm snout-vent length. description of adult; see REMARKS.Type-locality, Larvae are of the pond type. Their ground color "Chiloweyuck, W. T. [Chiloweynck, Washington is deep brown to greenish brown; dark spotting may be evident or not on the dorsum and upper sides, and bia].Territory]"H010type,[nowfemale,ChilliwackU.S. Lake,Nat!. Mus.British4708a,Colum•re• distinct yellowish spots may be present or not on the ceived from A. Campbell, 1859. Cochran, 1961, sides of the trunk and tail. The glandular ridge is dis• lists USNM 4708a and 7021 as cotypes [syntypes], tinct at the juncture of the dorsal tail fin and the mus• the latter from "Puget Sound (Washington)," col• cular portion of the tail. The venter is uniform slate lected by the U.S. Exploring Expedition, 1841. gray or blackish brown faintly flecked with cream in Baird mentions USNM 7021, but not as a type, breeding males; it is light brown, flecked and spotted and he records the collector as "Dr. Kennerly." with cream, and the gular region is cream colored in breeding females. Size at metamorphosis under nat• ural conditions is not known. There are no apparent differences between neotenic larvae and those destined to transform. • DESCRIPTIONS.Egg masses are described by Slater (1936), Bishop (1947), Stebbins (1951), Snyder (1956, 1960), and Knudsen (1960); larvae by Storer (1925), Logier (1932), Carl & Cowan (1945), Watney (1941), Bishop (1947), Stebbins (1951), Farner & Kezer (1953), and Snyder (1956); metamorphic behavior by Watney (1941), Carl & Cowan (1945), and Snyder (1956); sec• ondary sexual differences of the adults and of the neo• tenic larvae by Snyder (1956); the condition of the reproductive organs at breeding time by Snyder (1956); courtship activity by Knudsen (1960); larval egg depo• sition by Slater (1936), and Snyder (1956); cranial osteology by Larsen (1958), osteology and phylogeny by Tihen (1958); and thyroid function by Schmidt (1956). Adults are described by Watney (1941), Bishop (1947), and Stebbins (1951). Spermatophores have not been described. • ILLUSTRATIONS.See Bishop (1947) for photographs of adults, Stebbins (1951) for drawings of adult and larval stages, Snyder (1956) for photographs of adults, subadults, young larvae, metamorphic stages of 5-month-old and year-old larvae, and dorsal and ventral views of neotenic larvae, and Henry & Twitty (1940) for photographs of an embryo and early (40 mm total length) larva. Adequate illustrations of eggs are not available. • DISTRIBUTION.The species occurs from southeast• ern (from May Island at 54°30' N. latitude) south to the mouth of the Gualala River, Sonoma County, . It is confined to coastal forests west of the Cascade Divide, but occurs from sea level to timberline. The range includes , MAP. Solid circles mark type-localities. Hollow cir• ; and Cypress, Whidbey, Bainbridge, cles are other selected localities. After Goode Base and Vashon Islands, Washington. Map 202, © University of Chicago 1937. 6.2

Ckondrotus paroticus: Cope, 1887:88. Transfer of A. Bishop, Sherman C. 1947. Handbook of salamanders. paroticum 1;0 ChOndrotUB. Comstock Publ. Co., Uhaca, New York. xiv + 555 Ambystoma paroticum: Grinnell & Camp, 1917:139. Carl,pp.G. CUfford.1944. The natural history of the Emended generic name. Stejneger & Barbour also Forbidden Plateau area, Vancouver IslaJ;1d,British proposedbecause Grinnellthis combination& Camp (12precededDecemberthem1917),(11 Julybut Columbia. Rept. Prov. Mus. Nat. Hist. & Anthro• 1917), the latter are cited as the authority. Carl,pol.G.forClifford,1943, pp.& 18-40.Ian McTaggart Cowan. 1945. • DEFINITION.Three phalanges are present in the Notes on the salamanders of British Columbia. Co• 4th toe; prevomerine teeth occur in 4 groups, 2 pos• pei&,1945:48-44. terior to the choanae and 2 medial to the choanae; the body is uniform dark blackish brown above and lighter Cochran, Doris M. 1961. Type specimens of reptiles brown below; the parotoid glands and glandular tail andseum.ampl1ibiansU.S. Natl.inMus.the UnitedBull., (220):xvStates National+ 291. Mu• ridge usually are lighter than the dorsal surface; there are 10 or 11 grooves. Cope,ciesEdwardof the Amblystomidae.Drinker. 1867. AProc.reviewAcad.of Nat.the spe•Sci. • REMARKS.Prevomerine teeth may be broken into Plliladelphia, ser. 2 19:166-211. 3 or 4 series (Bishop, 1947). - cies1886.ofSynonymicBufo and Rana,fist ofWliththe NorthdescriptionsAmericanof somespe• 2. Amby.toma gracile decorticatum Cope new species of batrachia, from sRecimens in the National Museum. Proc. Amer. Philos. Soc.,23:514• 526. A mblystoma decorticatum Cope, 1886:522. Type-local• - 1887. The hyoid structure in the amblystomid sal• Holotype,ity, "Port U.S.Simpson,Natl. Mus.Alaska"14493,[BritishcollectedColumbia].by T. It amanders. Amer. Nat., 21:87-88. Streets, 9 December 1885. Dunn, Emmett Reid. 1926. The status of Siredon Chondrotus decorticatus: Cope, 1887:88. Transfer of A. decorticatum to Ckondrotus. - gracilis1944. NotesBaird.on Copeia,the salamanders(154):135-136.of the Ambystoma Ambystoma decorticatum: Stejneger & Barbour, 1917: gracile group. Copeia, 1944:129-130. 9. Emended generic name. Farner, .Donald S., & James Kezer. 1953. Notes on Ambystoma gra..cile decorticatum: Dunn, 1944:130. the and reptiles of Crater Lake Na• tional Park. Amer. Midland Nat., 50:448-462. • DEFINITION.Four phalanges are present in the Grinnell, Joseph, & Charles L. Camp. 1917. A dis• 4th toe; prevomerine teeth occur in 2 groups postero• tributional list of the amphibians and reptiles of medial to the choanae; the dorsum is marked with ir• California. Univ. California Pub!. Zool., 17:127-208. Henry, Wilbur V., & Victor C. Twitty. 1940. Contri• bronzeregular inlightlife) spotson a darkand dotsbackground;(whitish,tllereyellowish,are 11 or butions to the life histories of Dicamptodon ensatus 12 costal grooves. and Ambystoma gracile. Copeia, 1940:247-250. • REMARKS.Slater (1936) and Bishop (1947) refer Knudsen, Jens W. 1960. The courtship and egg mass to individuals of A. g. gracile from a pond near Deer of A mbY8toma gracile and Arnbystoma macrodacty• lum. Copeia 1960:44-46. tains,Lake, Washington,6 miles S SolasDucmarkedHot Springs,above withOlympicyellowMoun•flecks Larsen, John B., Jr. 1958. Comparative cranial os• and spots. Examination shows that these specimens teology of the ambystomid salamanders. Univ. are transformed breeding males, that they have 3 phalanges in the 4th toe (as in A. g. gracile), that the Logier,WashingtonE. It S.Tbe8lis1932.Dissert.,Some account48 pp., 11/ls.0 the amphib• ians and reptiles of British Columbia. Trans. Roy. theprevomerinechoanae teeth(gracile),are inand3 thatgroupsthereposteromedial.are 11 costalto Canadian Inst., 18:311-336. grooves (as in A. g. decorticatum). A similarly Schmidt, Anthony J. 1956. Thyroid function in marked individual was collected by Slater (1980) at the northwestern salamander, A mbystoma gracile Forks, Washington. The possibility exists of an un• (Baird). Jour. Exptl. Zoo!., 133:539-558. described Olympic Mountam form (Dunn, 1944; Steb• Slater, James R. 1930. AmbY8toma decorticatum bins, 1951). Carl (1944) states that bronze spottirig Cope rediscovered in Washington. Copeia, 1930:87. is found in adults from Croteau Lake, VancouverIsland, - 1936. Notes on A mbystoma gracile Baird and A m• British Columbia, where only A. fl. gracile is reported bystoma macrodactylum Baird. Ibid., 1936:234-236. to occur. It is possible that indiVIdualswith this color Snyder, Richard C. 1956. Comparative features of pattern represent variants from the norm. Cowan the life histories of Ambystoma gracile (Baird) from populations at low and high altitudes. Copeia, A.(Carlg. decorticatum& Cowan, from1945)islandsexaminedadjoiningtwo HecatespecimensStrait,of 1956:41-50. British Oolumbia, that were marked dorsally by cii'• - 1960. The egg masses of neotenic Ambystomagra• cular, honey-colored spots up to 2 mm in diameter. cile. Ibid., 1960:267. Stebbins, Robert C. 1951. Amphibians of western COMMENT North America. Univ. California Press, Berkeley. ix + 539 pp. There is a need for intensive collecting and studies of Stejneger, Leonhard, & Thomas Barbour. 1917. A variation in northern Washington and southern British Columbia to clarify the status of populations there and checktiles. listHarvardof NorthUniv.AmericanPress, Cambridge,amphibiansMassachu•and rep• the nature of the zone of intergradation. setts. iv + 125 pp. Common names are omitted from the subspecies. Storer, Tracy I. 1925. A synopsis of the amphibia British Columbia salamander is descriptive for the sub• of California. Univ. California Pub!. Zoo!.,17:1-342. species decorticatum, but brown salamander for the Tihen, Joseph A. 1958. Comments on the osteology subspecies gracile is essentially meaningless. The basic and phylogeny of ambystomatid salamanders. Bull. objection is that these "official" common names show Florida State Mus., 3:1-50. no relationship to the common name for the species. Watney, Gertrude M. Smith. 1941. Notes on the life history of Ambystoma gracile Baird. Copeia, 1941: LITERATURECITED 14-17. Baird, Spencer F. 1859. Report on reptiles collected N~til()nalIssued 81ScienceDecemberFoundation1963. Publicationgrant G24231.is sup~orted© Ameri•by on the surveYt,.pt.4, (4):18, pl. 44, flg. 2. In Report can Society of Ichthyologists and Herpetologists 1968. forniaU.S. Pacificand Oregon),oK. R. Explorationvol. 10, Williamson'sand SurveyRoute.(Cali•