Potomotyphlus kaupii (Berthold, 1859)
© 1979 James L. Patton (1 of 1)
The body as a whole is laterally compressed so that it is deeper than it is wide. Additionally, the body possesses a dorsal keel or fin that is especially prominent on the posterior portion of the body. Nuchal grooves are positioned laterally and ventrally, and vary in degrees of distinction. The primary annular grooves are interrupted dorsally. Along the body there are 83 - 102 primary annuli with no secondary grooves. The last 3 - 6 annuli are only laterally distinct and there are no annuli present from the approximate level of the cloaca to the terminal tip of the body. Dermal and subdermal scales are absent. The terminus shows marked sexual dimorphism with females having a narrower and more pointed terminus. The cloacal disk is elongate anteriorly and rounded posteriorly. The disk shows variation in whether it is depressed, but is surrounded by fleshy folds of skin in both sexes. Some specimens show anterior denticulations that are elongate along the cloacal disk. Anal denticulations range from 7 to 11 with a similar number for the posterior and anterior edge of the cloaca. Paired anal papillae are present in a minority of male specimens (Maciel and Hoogmoed 2011).
Potamotyphlus kaupii can be differentiated from most other Brazilian Amazonian caecilian species by having an anteriorly elongated cloacal disk and 83 – 102 primary annuli. More specifically, the absence of dermal scales differentiates P. kaupii from all Brazilian Amazon Brasilotyphlus, Caecilia, and Microcaecilia. The lack of a true tail and a snout that projects beyond the mount differentiates P. kaupii from Rhinatrema bivittatum and R. ron. The focal species can be differentiated from Siphonops annulatus by having tentacles that are closer to the nostrils than the eyes and lacking white rings around the body (Maciel and Hoogmoed 2011). From other member of the family Typhlonectidae, of which it is a member, it can be differentiated by lacking choanal valves with long medial apertures (Wilkinson and Nussbaum 1997). More specifically, P. kaupii can be differentiated from Nectocaecilia petersi by the focal species having a laterally compressed body with a dorsal fin (Maciel and Hoogmoed 2011), fewer primary annuli, and fewer vertebrate. Potamotyphlus kaupii has more primary annuli and vertebrate than Chthonerpeton indistinctum. From Atretochoana eiselti, Potamotyphlus kaupii is unique in having an elongated cloacal disk, a different pattern of cloacal disk denticulations, and relatively smaller head, nuchal collars, and anterior body in comparison with the rest of the body. Lastly, P. kaupii has more vertebrate than members of its sister genus, Typhlonectes (Wilkinson and Nussbaum 1997).
In life, Kaup’s caecilians are shades of gray or brown with the grooves along the body possibly being darker. A freshly dead female had a blue-grey color on its body and a paler head. The dead specimen had a white-blue underside and the grooves of the primary annuli were darker than the rest of the body. A live specimen had grey dorsal coloration that transitioned into a blue head and a whitish ventral surface (Maciel and Hoogmoed 2011). In preservative, the range of dorsal coloration is dark grey-brown to blue-grey (Wilkinson and Nussbaum 1997).
There is sexual dimorphism that is manifested in the cloacal region with the males having a more sunken disc than females and smaller females having no cloacal depression. Females also have a narrower and more pointed terminus. Lastly, anal papillae are not present in all individuals (Maciel and Hoodmoed 2011).
Distribution and Habitat
Country distribution from AmphibiaWeb's database: Brazil, Colombia, Ecuador, French Guiana, Guyana, Peru, Venezuela
This aquatic species is found in inland wetlands, forests, and grasslands at elevations up to 500 m (Wilkinson et al. 2010).
Life History, Abundance, Activity, and Special Behaviors
Potamotyphlus kaupii is believed to be fully aquatic (Wilkson and Nussbaum 2006, Maciel et al. 2017). Specimens have been reportedly collected at night in a cataract area of shallow water at the edge of a river suggesting they can probably survive in running water (Maciel and Hoogmoed 2011).
They are known to eat small fish in the wild (Presswell et al. 2002) and are regularly caught in shrimp traps in Belém, Brazil (Maciel and Hoogmoed 2011).
Like most other aquatic members of the family Typhlonectidae, P. kaupii possesses lungs. However, the species also has many circulatory and respiratory adaptations similar to the lungless A. eiselti, indicating that P. kaupii utilizes some form of cutaneous respiration (Maciel et al. 2017).
Trends and Threats
Relation to Humans
Possible reasons for amphibian decline
General habitat alteration and loss
Initially, the species was thought to be the sister taxa to the lungless A. eiselti based on 141 morphological characters and life history (Wilkson and Nussbaum 1999). However, Maximum Likelihood analysis on 12S, 16S, and CO1 mitochondrial DNA along with CXCR4, H3, SIA, Slc8a3, and Rag1 nuclear genes indicates that P. kaupii is sister to the members of the genus Typhlonectes and that the shared morphological characters with A. eiselti are the result of convergent evolution. The results further indicate that A. eiselti is sister to the clade composed of P. kaupii and the members of the genus Typhlonectes; while, this relationship is poorly supported in the molecular analysis, it was a consistent result and is supported in a joint molecular and morphological analysis (Maciel et al. 2017).
The families Typhlonectidae and Caeciliidae have well supported molecular and morphological evidence of being sister taxa (Maciel et al. 2017).
Potomotyphlus kaupii is within the family Typhlonectidae. As of 2019, P. kaupii was the only known species in the genus.
Potomotyphlus kaupii was first described and named Caecilia kaupii by Berthold 1859. Since it was first described, it has been given many different names including Caecilia dorsalis, Typhonectes dorsalis, Chthonerpeton microcephalum, Typhonectes kaupii, and Potomotyphlus melanochrus (Frost 2016).
Coloma, L. A., Guayassamin, J. M., Guerrero-Menèndez, P., (2011). ''Potomotyphlus kaupii''. In: NRL 2011. National Red List of Threatened Species. www.nationalredlist.org. Downloaded 3 December 2016. [link]
Frost, D. R. (2016). Amphibian Species of the World: an Online Reference. Version 6.0 Accessed 7 December 2016. Electronic Database accessible at http://research.amnh.org/herpetology/amphibia/index.html. American Museum of Natural History, New York, USA.
Maciel, A. O., Hoogmoed, M. S. (2011). ''Taxonomy and distribution of caecilian amphibians (Gymnophiona) of Brazilian Amazonia, with a key to their identification.'' Zootaxa, 2984, 1-53.
Maciel, A.O., Sampaio, M.I.C., Hoogmoed, M.S., Schneider, H. (2017). ''Phylogenetic relationships of the largest lungless tetrapod (Gymnophiona, Atretochoana) and the evolution of lunglessness in caecilians.'' Zoologica Scripta, 46(3), 255-263. [link]
Oliveira, U. S. C., Meneghelli, D., Messian, M. R., Gomes, I. B. S. R., Coragem, J. T. (2012). ''First record of Potomotyphlus kaupii (Berthold, 1859) (Gymnophiona: Typhlonectidae) for the state of Rondônia, Brazil.'' Herpetology Notes, 5, 155-156. [link]
Presswell, B., Gower, D. J., Oomen, O. V., Measey, J., Wilkinson, M. (2002). ''Scolecophidian snakes in the diets of south American caecilian amphibians.'' Herpetological Journal, 12, 123-126. [link]
Wilkinson, M. and Nussbaum, R.A. (1997). ''Comparative morphology and evolution of the lungless caecilian Atretochoana eiselti (Taylor) (Amphibia: Gymnophiona: Typhlonectidae).'' Biological Journal of the Linnean Society, 62, 39-109.
Wilkinson, M., Measley J., La Marca, E., Coloma, L. A., Ron, S., Castro, F., (2010). ''Potomotyphlus kaupii''. In: IUCN 2010. Red List of Threatened Species. www.iusnredlist.org. Downloaded 21 March 2019.
Wilkinson, M., and Nussbaum, R. A. (1999). ''Evolutionary relationships of the lungless caecilian Atretochoana eiselti (Amphibia: Gymnophiona: Typhlonectidae).'' Zoological Journal of the Linnean Society, 126, 191-223.
Originally submitted by: David Trevino Ledesma (first posted 2019-03-25)
Edited by: Ann T. Chang (2019-09-24)
Species Account Citation: AmphibiaWeb 2019 Potomotyphlus kaupii: Kaup's Caecilian <https://amphibiaweb.org/species/1960> University of California, Berkeley, CA, USA. Accessed Sep 25, 2023.
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Citation: AmphibiaWeb. 2023. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 25 Sep 2023.
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