Description
Dendrotriton chujorum is a small, lungless salamander with adult females measuring 19.9 - 27.6 mm in standard length and males ranging between 23.1 – 31.6 mm in standard length. Its head is longer than wide. Protrusive eyes can be found on the head with the eye length being smaller than the interocular distance. The distance from the eyes to the nose is smaller than the eye length. The species has 45 maxillary and premaxillary teeth total, this number includes the 15 vomerine teeth which curve forward from the midline to the internal nares’ midpoint. The legs are relatively short compared to other members of their genus. In the holotype, the limbs are separated by 1 intercostal fold, and the axilla to groin distance measures 15.5 mm. The hands have a width of 3.6 mm with 4 digits, and the finger length decreases in the order 3, 4, 2, 1. The feet have a width of 4.4 mm with 5 digits with their toe length decreasing in the order 3, 4, 2, 5, 1. On both the hands and feet, the first digit is the shortest and have webbing all the way to the tip while there is only moderate webbing on the other digits. The vent is folded. The holotype has a 30.3 mm tail length (Campbell et al. 2010).

DIAGNOSIS:

Dendrotriton chujorum can be distinguish from other Dendrotriton species by its wide head, large feet, and short limbs. It is also one of the smaller species of Dendrotriton, but is not smaller than the D. cuchumatanus or D. sanctibarbus. Dendrotriton chujorum can be further differentiated from D. cuchumatanus by the former having smaller nostrils in adult males, larger feet, and smaller legs. Dendrotriton chujorum can further be differentiated from D. santibarbarus by the former having shorter limbs, smaller nostrils, and fewer number of maxillary-premaxillary teeth. Lastly, they can also be differentiated from D. rabbi due to D. chujorum having a smaller body size, wider head, larger feet, and larger nostrils in adult females (Campbell et al. 2010).

COLORATION:

In life, males have beige coloring in the dorsal surface of the head and body with dark brown mottling. The dorsal surface of the tail is dusty red. The ventral surfaces of the body and tail are purplish gray outlined with hefty white stippling on both sides that extends all the way to the tail. The chin is smoky gray but turns yellow at the throat. The lateral surfaces are dark brown with a yellow line extending along a glandular ridge. The limbs’ dorsal surfaces contain yellow and pale brown botches with pinkish-yellow ventral surfaces. The distal regions of the digits are dark brown (Campbell et al. 2010).

When in preservative, the adult female dorsal surface is medium brown, and the pale glandular ridge that extends to the groin from the axilla takes on a yellowish color. The ventral surfaces and the sides of the body are dark, with the ventrum being darker than the sides of the body (Campbell et al. 2010).

Preserved adult male heads and bodies have irregular, dark brown mottling. The sides of the body take on a cream-like color with irregular, dark brown blotches. Lastly, the ventral surfaces of the body, throat, and tail turn a pale color with tiny, black stippling (Campbell et al. 2010).

The dorsal surface of a juvenile female in preservative is pale cream color with dark brown sides and a darker ventrum (Campbell et al. 2010).

VARIATION:

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Guatemala

	View distribution map in BerkeleyMapper.
	View Bd and Bsal data (1 records).

Dendrotriton chujorum are native to Guatemala and are only known from along a small road from Nentón to San Mateo Ixtatán in the northern portion of the Sierra de los Cuchumatanes with an elevational range of 2,629 – 2,799 m (IUCN 2020). The individuals collected for the species description were found in a remnant hardwood forest on slopes drained by the upper tributaries Río Grijalva (Campbell et al. 2010).

Life History, Abundance, Activity, and Special Behaviors
All specimens for the species description were found in bromeliad plants located 3 – 10 m above the ground indicating that they are arboreal (Campbell et al. 2010).

Larva
As members of the family Plethodontidae, D. chujorum is assumed to have direct development with terrestrially laid eggs. Other cloud forest species in the family have been observed to mate year-round rather than seasonally (Chan 2003).

Trends and Threats
The IUCN Red List of Threatened Species has designated D. chujorum as "Critically Endangered" because as a bromeliad specialist, D. chujorum is especially sensitive to changes in habitat. Currently, the species' habitat is threatened by deforestation perpetrated by small-holder farming or firewood harvesting. Climate change also poses an additional threat to the habitat as the bromeliads it occupies are sensitive to increasing variations in precipitation, especially increasing occurrences of droughts. Forest preservation as a method of conservation is currently being researched in part of D. chujorum’s habitat in San Mateo Ixtatán, Guatemala (IUCN 2020).

If Batrachochytrium salamandrivorans were to make it to Central America, D. chujorum may also be threatened with disease (IUCN 2020).

Possible reasons for amphibian decline

General habitat alteration and loss
Habitat modification from deforestation, or logging related activities
Subtle changes to necessary specialized habitat
Habitat fragmentation
Climate change, increased UVB or increased sensitivity to it, etc.

Comments
The adult external nares of D. chujorum were used to help place it phylogenetically. Dendrotriton chujorum, D. kekchiorum, D. rabbi, and D. xolocalcae all shared these external adult nares that were smaller compared to the juvenile and subadult state (Campbell et al. 2010).

ETYMOLOGY:

References

Campbell, J. A., Smith, E. N., Streicher, J., Acevedo, M. E., Brodie, E. D. Jr. (2010). "New salamanders (Caudata: Plethodontidae) from Guatemala, with miscellaneous notes on known species." Miscellaneous Publications Museum of Zoology University of Michigan, 200, 1-66. [link]

Chan, L. M. 2003. Seasonality, Microhabitat and Cryptic Variation in Tropical Salamander Reproductive Cycles. Biological Journal of the Linnean Society 78.4: 489-496.

IUCN SSC Amphibian Specialist Group. (2020). "Dendrotriton chujorum (amended version of 2020 assessment)." The IUCN Red List of Threatened Species 2020: e.T194310A176232851. https://dx.doi.org/10.2305/IUCN.UK.2020-3.RLTS.T194310A176232851.en. Downloaded on 17 February 2021.

Species Account Citation: AmphibiaWeb 2023 Dendrotriton chujorum <https://amphibiaweb.org/species/7573> University of California, Berkeley, CA, USA. Accessed Apr 19, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 19 Apr 2024.

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