Description
Description: A robust, medium-sized ambystomatid salamander. Terrestrial adults reach a maximum SVL of 76.6 mm in males and 84.8 mm in females, a maximum tail length of 75.3 mm in males and 71.6 mm in females, and a maximum total length of 164.4 mm in males vs. 163.5 mm in females. Males have longer tails and shorter bodies than females. Costal grooves number 11-12 (average 11.0). Vomerine teeth usually in two series (range 42-70, mean 50.4) with a midline diastema. Glandular ridge on proximal third to half of the tail. Parotoid gland is present. Neither the ridge nor the parotoid gland are as well-defined as in A. gracile (Anderson 1961; Anderson 1978).

Diagnosis: Larvae are reddish or pinkish with dense black marks or reticulations on the dorsal surface and an unmarked venter. Well-developed gills with each middle arch having about 20 gill rakers. Pterygoid teeth 10-10. Vomerine teeth about 30-30. Maxillary-premaxillary teeth about 30-30. Splenial teeth about 50. Webbing involves only the metatarsals and metacarpals (Taylor 1941).

Hatchlings are dark-brown to black, while older larvae are patterned with black and yellow (Anderson and Webb 1978; Webb and Baker 1984). The typical larval coloration consists of black and yellow mottling arranged in longitudinal rows (Taylor 1941; Shannon 1951), although specimens from Yépomera can have more of a silver-gray to brown background color (Shaffer 1983). Metamorphs are uniform olive-brown, gradually changing to brownish-black with light yellow spots at maturity in Chihuahua specimens (Van Devender 1973) or being relatively uniformly colored with only occasional spots in Durango specimens (Anderson 1961). Tanner (1989) also reported that larvae transited from the typical mottled larval pattern to a darker, more uniform color, before the yellow-spotted adult coloration began to emerge. Terrestrial adults generally have large distinct yellow spots on a dark background that may coalesce into veins or streaks; some individuals have little to no spotting (Raffaëlli 2007). Paedomorphs are blackish with paler marks (Raffaëlli 2007).

Similar species: Larvae of this species can be distinguished from sympatric Ambystoma tigrinum stebbinsi, the Sonora tiger salamander, by coloration and gill raker count (USFWS 2002); A. rosaceum larvae are pinkish in color and have dark patterning on the dorsum and sides (Taylor 1941), plus fewer gill rakers (9-15) than tiger salamanders in Arizona and Mexico (15-24) (Collins 1979). A. tigrinum stebbinsi larvae are gray dorsally and lack dark patterning (USFWS 2002).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Mexico

View distribution map in BerkeleyMapper.

Endemic to Mexico. Found in the Sierra Madre Occidental at 1,675-3,100 m asl. The range extends southward from eastern Sonora (Anderson 1961; O'Brien et al. 2006; Rorabaugh 2008; Enderson et al. 2009) and Chihuahua (Anderson 1961; Van Devender 1973; Van Devender and Lowe 1977; Webb and Baker 1984; Enderson et al. 2009) into eastern Sinaloa (Anderson and Webb 1978; Enderson et al. 2009), Durango (Anderson 1961), Zacatecas (Anderson and Webb 1978), Jalisco (Shaffer et al. 2008), and Nayarit (Canseco-Márquez et al. 2007). The type locality is considered to be Majorachic, Chihuahua (but see the Comments section below). Ambystoma rosaceum generally occurs in high-elevation pine and pine-oak forest with small, shallow, slowly moving streams (Rorabaugh 2008), as well as springs and ponds (Tanner 1989). At Yepómera, Chihuahua, it is found in streams and springs in grassland rather than in pine-oak forest (Van Devender 1973; Van Devender and Lowe 1977). Adults are also found in farmland and ranchland and can breed in livestock ponds as well as streams. In Sonora this species has been found in highland marginal thornscrub habitat (Hale 2001; Rorabaugh 2008) and in tropical deciduous forest (Enderson 2006).

Life History, Abundance, Activity, and Special Behaviors
Breeding takes place in higher-elevation streams, ponds, and pools. Breeding has been reported to occur in Durango and Chihuahua after the onset of summer rains, which begin in late June/early July in Chihuahua (Anderson 1961). It has also been reported to take place earlier (April-May) at higher elevations, in the dry season (March-June) for Chihuahua and Sinaloa (Webb and Baker 1984; Anderson and Webb 1978; Tanner 1989).

Eggs are darkly pigmented at both the animal and vegetal poles (Anderson and Webb 1978). In streams, eggs have been found attached singly to the underside of large, flat rocks (Anderson and Webb 1978). Tanner (1989) reported finding eggs in large, clear seep-fed ponds (2-3 feet deep) in Chihuahua at the beginning of April. Clutches were attached in smaller clusters ranging from 2-12 eggs to tree roots that extended down into the pool, between rocks, or attached to pine needles and other debris; a cluster of 30 eggs was also found attached to the lower edge of a large boulder, and some small clusters were actually strings of 3-6 eggs, or were laid singly and adhering in clusters (Tanner 1989; Anderson 1961). In Chihuahua and Durango, streams used for breeding had a gentle gradient, and were in or near a meadow; associated pools with larvae were 6-12 inches deep (Anderson 1961). The breeding period is likely to be extended; new hatchlings can be found alongside much larger larvae (Webb and Baker 1984; Tanner 1989). In Chihuahua, larvae that are spawned in April generally transform in the same year (mid-July-October), before the onset of winter (Tanner 1989). Growth is rapid after the onset of summer rains (Tanner 1989). Some larvae spawned later, in May, may winter over to the following year (Anderson 1961; Anderson and Webb 1978; Tanner 1989); Webb and Baker (1984) found eggs and small larvae in late May, in a high-elevation (3750 m), permanent stream in Chihuahua. In Sierra Surutato, Sinaloa, where the streams are thought to be permanent, large mottled larvae (possibly paedomorphs) were observed in October and November (Anderson and Webb 1978).

Some individuals metamorphose into terrestrial salamanders as adults while others remain as aquatic, gilled paedomorphs. Aquatic, paedomorphic adults and larvae have been found in montane streams, pools, and "impounded springs" (Rorabaugh 2008). Larvae have also been found in plunge pools below waterfalls (Van Devender 1973; O'Brien et al. 2006) and an artificial spring-fed pond with aquatic vegetation and a sandy bottom in high-elevation grassland habitat (Van Devender 1973), as well as a sluggish stream (depth 3 feet, width 20 feet) with aquatic vegetation and a silt substrate. Larvae and paedomorphs were found in a permanent artificial water body in Chihuahua (a tank with water surface area of 2 ha and red, muddy water; Collins 1979), in contrast to Tanner's (1989) report of finding no paedomorphs in Chihuahua fieldwork between 1956-1972. Terrestrial adults have been found under streamside logs and rocks (Webb and Baker 1984).

Larval stomach contents of specimens from Yepomera, Chihuahua included aquatic snails and ostracods (Van Devender 1973).

This species has parotoid glands, which function to exude skin toxins as an antipredator defense (Brodie 1977). Terrestrial adults of other species of Ambystoma that have parotoid glands (A. gracile, A. maculatum, and A. talpoideum) also have a specific antipredator posture, bending their head as sharply downward as possible (Brodie 1977). It is likely that A. rosaceum uses a similar posture when threatened, but this has not been confirmed. Ambystomatid salamanders also have high concentrations of toxin-secreting granular glands on the dorsal surface of the tail (A. rosaceum has a glandular ridge on the proximal third to half of the tail; Anderson 1961), although these are not noticeable in most ambystomatid species until the salamander is threatened and skin secretions are exuded (Brodie 1977). Tail lashing and/or elevation is another ambystomatid antipredator defense (Brodie 1977); A. rosaceum may exhibit these behaviors.

Trends and Threats
Predation by non-native fish may be a threat; Tanner (1989) reported that although this species was found in nearly all small streams, springs and ponds in montane western Chihuahua, it was absent from larger streams and rivers where fish were present. Habitat loss due to agriculture may also be a threat (Shaffer et al. 2008). It can tolerate some habitat disturbance. In particular, this species does well in livestock areas if breeding habitat (livestock ponds) are available (Shaffer et al. 2008). The range overlaps with several protected areas, although better habitat protection is needed throughout the range (Shaffer et al. 2008). It is listed as Category Pr (Special Protection) by the Government of Mexico (Shaffer et al. 2008).

Possible reasons for amphibian decline

General habitat alteration and loss
Intensified agriculture or grazing
Predators (natural or introduced)
Introduced competitors

Comments
It may be a species complex, with northern and southern populations representing distinct lineages (Shaffer 1983). Four subspecies were recognized by Shannon (1951), mainly on the basis of differing larval coloration in various populations, but Anderson (1961) did not find these subspecies to be valid. However, Shaffer (1983) subsequently recognized two subspecies (A. r. rosaceum, in the northern part of the range, and A. r. nigrum, in the south) on the basis of allozyme differences. Highton (2000) thought that the data in Shaffer and McKnight (1996) indicated A. rosaceum might actually be three species.

Although two papers (Van Devender 1973 and Van Devender and Lowe 1977) reported that A. rosaceum and A. tigrinum were sympatric in streams and springs of Yépomera, Chihuahua, Tanner (1989) pointed out that the larval specimens were always identified as A. rosaceum and the adults were always identified as A. tigrinum, and concluded from patterning that all of these specimens were in fact A. rosaceum (supported by Shaffer's (1983) allozyme analysis of other Yépomera specimens). Anderson (1961) thought that the two species described in Taylor's (1941) paper were both likely to be A. rosaceum, with the second species simply in the process of metamorphosis.

Interbreeding between A. rosaceum and A. tigrinum appears to be rare or non-existent (Shaffer 1983).

Although Taylor (1941) is regarded as the species authority, Webb and Baker (1984) noted that this species was actually first described by Owen (1844) as Axolotes maculata. According to Webb and Baker (1984), Bishop (1945) shared this view and noted that Owen's name appeared to be a senior synonym of Taylor's A. rosaceum, but that the name maculata was already in use for Ambystoma maculata (then referred to as Lacerta maculata). Webb and Baker (1984) note that Owen's type locality was "in fluviis Sierrae Madre, Chihuahua, lat. 26°6'N, long. 106°50'W", or about 13 km east of Guadalupe y Calvo; they reported finding A. rosaceum larvae in most permanent streams in the area, lending credence to Owen's report.

References

Anderson, J. D. (1961). ''The life history and systematics of Ambystoma rosaceum.'' Copeia, 1961, 371-377.

Anderson, J. D. (1978). ''Ambystoma rosaceum Taylor. Tarahumara salamander.'' Catalogue of American Amphibians and Reptiles, 206, 1-2.

Anderson, J. D., and Webb, R. G. (1978). ''Life history aspects of the Mexican salamander, Ambystoma rosaceum (Amphibia, Urodela, Ambystomatidae).'' Journal of Herpetology, 12, 89-93.

Bishop, S. C. (1945). ''The identity of Siredon harlanii Dumeril, Bibron and Dumeril and Axolotes maculata Owen.'' Herpetologica, 3, 24.

Brodie, E. D. Jr. (1977). ''Salamander antipredator postures.'' Copeia, 1977, 523-535.

Canseco-Marquéz, L., Smith, E. N., Ponce-Campos, P., Flores-Villela, O., and Campbell, J. A. (2007). ''A new species of Tantilla (Squamata: Colubridae) of the calamarina group from Volcán Ceboruco, Nayarit, Mexico.'' Journal of Herpetology, 41, 220-224.

Collins, J. P. (1979). ''Sexually mature larvae of the salamanders Ambystoma rosaceum and A. tigrinum velasci from Chihuahua, Mexico: taxonomic and ecologic notes. .'' Journal of Herpetology, 13, 351-354.

Enderson, E. F. (2006). ''Tarahumara Salamander (Ambystoma rosaceum Taylor 1941).'' Sonoran Herpetologist, 19, 38-40.

Enderson, E. F., Quijada-Mascareñas, A., Turner, D. S., Rosen, P. C., and Bezy, R. L. (2009). ''The herpetofauna of Sonora, Mexico, with comparisons to adjoining states.'' Check List, 5, 632-672.

Hale, S. F. (2001). ''The status of the Tarahumara Frog in Sonora, Mexico based on a re-survey of selected localities, and search for additional populations.'' Report to United States Fish & Wildlife Service, Phoenix.

Highton, R. (2000). ''Detecting cryptic species using allozyme data.'' The Biology of Plethodontid Salamanders. R.C. Bruce, R.G. Jaeger, and L.D. Houck, eds., Kluwer Academic/Plenum Publishers, New York, New York, 215-241.

O'Brien, C., Flesch, A. D., Wallace, E., Bogan, M., Carrillo-Percástegui, S. E., Jacobs, S., and van Riper, C. III. 2006. Biological inventory of the Río Aros, Sonora, Mexico: a river unknown. Final report to T&E, Inc. 20 June 2006

Owen, R. (1844). ''Characters of a new species Axolotl.'' Annals and Magazine of Natural History, Series 1, 14, 23.

Raffaëlli, J. (2007). Les Urodèles du monde. Penclen Edition, France.

Rorabaugh, J. C. (2008). ''An introduction to the herpetofauna of mainland Sonora, México, with comments on conservation and management.'' Journal of the Arizona-Nevada Academy of Science, 40, 20-65.

Shaffer, B. (1983). ''Biosystematics of Ambystoma rosaceum and A. tigrinum in northwestern Mexico.'' Copeia, 1983, 67-78.

Shaffer, B., Parra-Olea, G., Wake, D., and Ponce-Campos, P. 2008. Ambystoma rosaceum. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4. www.iucnredlist.org. Downloaded on 19 December 2010.

Shaffer, H. B., and McKnight, M. L. (1996). ''The polytypic species revisited: genetic differentiation and molecular phylogenetics of the Tiger Salamander Ambystoma tigrinum (Amphibia: Caudata) complex.'' Evolution, 50, 417-433.

Shannon, F. A. (1951). ''Notes on a herpetological collection from Oaxaca and other localities in Mexico.'' Proceedings of the U. S. National Museum, 101, 465-484.

Tanner, W. W. (1989). ''Amphibians of Western Chihuahua.'' Great Basin Naturalist, 49, 38-59.

Taylor, E. H. (1941). ''Two new ambystomid salamanders from Chihuahua.'' Copeia, 3, 143-146.

U. S. Fish and Wildlife Service (2002). Sonora tiger salamander (Ambystoma tigrinum stebbinsi) recovery plan. U. S. Fish and Wildlife Service, Phoenix, Arizona.

Van Devender, T. R. (1973). ''Populations of Ambystoma tigrinum and A. rosaceum in Chihuahua, Mexico.'' Journal of the Arizona Academy of Science, 8, 34.

Van Devender, T. R., and Lowe, C. H. Jr. (1977). ''Amphibians and reptiles of Yepómera, Chihuahua, Mexico.'' Journal of Herpetology, 11, 41-50.

Webb, R. G., and Baker, R. H. (1984). ''Terrestrial vertebrates of the Cerro Mohinora Region, Chihuahua, Mexico.'' The Southwestern Naturalist, 29, 243-246.

Wilson, L. D., and McCranie, J. R. (1979). ''Notes on the herpetofauna of two mountain ranges in México (Sierra Fría, Aguascalientes, and Sierra Morones, Zacatecas .'' Journal of Herpetology, 13, 271-278.

Species Account Citation: AmphibiaWeb 2023 Ambystoma rosaceum: Tarahumara Salamander <https://amphibiaweb.org/species/3846> University of California, Berkeley, CA, USA. Accessed Nov 22, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 22 Nov 2024.

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