Description
Diagnosis: Andinobates daleswansoni is one of only two known dendrobatids with only four toes visible on the hind feet due to the fusion of toes I and II. This species differs from the other dendrobatid with four toes, A. dorisswansonae, in the following ways: coloration (bright red hood on the head, shoulders, and arms and a brown back and legs in A. daleswansoni, vs. dark brown to black with irregular orange spots in D. dorisswansonae), skin texture (mostly smooth with a few small, flat warts in the sacro-coccigeal region in A. daleswansoni, vs. completely smooth in D. doriswansonnae), amount of toe fusion (toes I and II totally fused in D. daleswansoni, vs. partially or totally fused in A. doriswansonnae) and testes color in males (cream with brown reticulation in A. daleswansoni, vs. dark brown in A. doriswansonnae) (Rueda-Almonacid et al. 2006).

Description: Andinobates daleswansoni is a small frog with a snout vent length ranging from 17.83-18.46 mm in males and 19.01-19.74 mm in females. The head is much narrower than the body. The snout is rounded when viewed from above and truncated when viewed from the side, with a rounded canthus rostralis and a flattened, vertical loreal region. D. daleswansoni does not have postrictal tubercles. It also lacks vomerine, maxillary, and premaxillary teeth. The length of the tongue is almost twice the width. Eyes are large and prominent with horizontally elliptical pupils. The oval-shaped tympanum and tympanal ring are obscured in the posterodorsal region, and there is no supratympanic fold. D. daleswansoni has relatively large hands with moderately expanded discs on the digits, except the pollex. Paired dorsal pads are present on the discs. Relative order of fingers is III>IV>II>I. The hind limbs are relatively short, with discs on the toes smaller than those on the fingers. The outer metatarsal tubercle is tubercle is elongated and protuberant, and is slightly larger than the inner metatarsal tubercle. Skin is smooth on the back and granular on the flank and belly. A few small warts are present in the sacro-coccigeal region and on the hind limbs. Males can be distinguished from females by the following characteristics: a thinner body, more granulated skin on ventral surfaces and thighs, a longer hand, the presence of vocal slits, and a single subgular vocal sac (Rueda-Almonacid et al. 2006).

In life, a bright red cephalic hood extends to the axilla, covering the suprascapular region and back of the arms. The rest of the body is brown, with sepia color and cinnamon infusions on the ventral surfaces, especially on the chin and throat. One or several yellow-orange dots may be present on the posterior surface of the trunk and thighs. The iris is black. In preservative, back and belly turn sepia or dark brown, and yellow-orange spots become gray (Rueda-Almonacid et al. 2006).

It can be distinguished from A. opisthomelas, with which it is sympatric up to 1800 m asl, by coloration: A. opisthomelas is reddish orange without patterning (Rueda-Almonacid et al. 2006).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Colombia

View distribution map in BerkeleyMapper.

This species is endemic to Colombia. It can be found in the northern Cordillera Central in the Municipality of Samaná, Department of Caldas, Colombia, between 1800-2000 m above sea level. Habitat is in the understory of primary and secondary cloud forests. The type locality is a transitional zone between warm and cold thermal floors on the eastern flank of the cordillera Central in Caldas. There are two rainy seasons and two dry seasons each year. Precipitation is over 400 mm per year and annual temperature ranges from 15-20˚C (Rueda-Almonacid et al. 2006).

Life History, Abundance, Activity, and Special Behaviors
A. daleswansoni is a diurnal species that prefers forested areas with high humidity and moderate leaf litter. When disturbed, this species seeks refuge under leaves, rocks, or in holes. Male vocalization resembles a cricket chirp. Males transport one or two tadpoles on their backs to bromeliads in trees (phytotelmata), where they complete their metamorphosis. Up to six tadpoles of different stages have been found within the same bromeliad. Other species of amphibians have also been found in the same bromeliad as the tadpoles, including the frogs Eleutherodactylus uranobates, Gastrotheca nicefori, and the salamander Bolitoglossa ramosi. Eggs are brown in preservative (Rueda-Almonacid et al. 2006).

A. daleswansoni is sympatric with A. opisthomelas up to around 1,800 m asl (Rueda-Almonacid et al. 2006). The two species can be easily distinguished by coloration.

Trends and Threats
The type locality is part of Bosques de Florencia National Natural Park, one of very few preserved forests of the cordillera Central's "coffee belt." Most of the region has been converted from forest to coffee plantation. Threats to A. daleswansoni include habitat loss both from deforestation and from illegal collection of bromeliads, where the larvae develop. This species is also threatened by illegal collection for the pet trade (Stuart et al. 2006).

It is protected under CITES Appendix II, with the 1987 CITES coverage of dendrobatids extended to include this species, which was described in 2006.

Relation to Humans
Like other brightly colored dendrobatids, A. daleswansoni most likely has skin toxins.

Possible reasons for amphibian decline

General habitat alteration and loss
Habitat modification from deforestation, or logging related activities
Intensified agriculture or grazing
Subtle changes to necessary specialized habitat
Habitat fragmentation
Intentional mortality (over-harvesting, pet trade or collecting)

Comments
A. daleswansoni is named after the late Dale Swanson (1927-2003) from Spokane, Washington, who dedicated his life to conserving biodiversity, especially in high-priority hotspots such as the Tropical Andes, where this species was first seen (Rueda-Almonacid et al. 2006).

This species is one of only two dendrobatids to have four toes on the foot due to the fusion of the first toe with the second. In A. daleswansoni the two toes are totally fused, while in A. dorisswansonae the two toes are partially or totally fused. The unique toe morphology could lead to the creation of a new genus in the future (Rueda-Almonacid et al. 2006). In 2011, the genus Dendrobates was subdivided into seven genera, including Andinobates by Brown et al (2011).

References

Rueda-Almonacid, J. V., Rada, M., Sánchez-Pacheco, S. J., Velásquez-Álvarez, A. A., and Quevedo-Gil, A. (2006). ''Two new and exceptional poison dart frogs of the genus Dendrobates (Anura: Dendrobatidae) from the northeastern flank of the Cordillera Central of Colombia.'' Zootaxa, 1259, 39-54.

Brown J.L., Twomey E., Amézquita A., De Souza M.B., Caldwell J.P., Lötters S., Von May R., Melo-Sampaio P.R., Mejía-Vargas D., Perez-Peña P., Pepper M., Poelman E.H., Sanchez-Rodriguez M., and Summers K. (2011). "A taxonomic revision of the Neotropical poison frog genus Ranitomeya (Amphibia: Dendrobatidae)." Zootaxa, 3083, 1-120. [link]

Stuart, S., Hoffmann, M., Chanson, J., Cox, N., Berridge, R., Ramani, P., Young, B. (eds) (2008). Threatened Amphibians of the World. Lynx Edicions, IUCN, and Conservation International, Barcelona, Spain; Gland, Switzerland; and Arlington, Virginia, USA.

Species Account Citation: AmphibiaWeb 2012 Andinobates daleswansoni <https://amphibiaweb.org/species/6773> University of California, Berkeley, CA, USA. Accessed Dec 26, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 26 Dec 2024.

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