Assessment Results
Atelopus flavescens
Cayenne Stubfoot Toad
Atélope Jaunâtre
Order:
Anura
Family:
Bufonidae
Synonym(s):
Atelopus vermiculatus, Atelopus spumarius barbotini, Atelopus franciscus
Assessed for:
French Guiana
on:
16 Feb 2023
by:
AArk/ASI Atelopus Assessment Workshop
Authors:
Plewnia, A., Lorioux-Chevalier, U., Le Pape, T., Fouquet, A., & Lötters, S.
IUCN Global Red List:
Least Concern (LC)
National Red List:
Least Concern (LC)
Distribution:
Brazil, French Guiana
Evolutionary Distinctiveness score:
6.142303611
Recommended Conservation Actions:
Additional Comments:
No taxonomic clarity for this species (A. vermiculatus, A. barbotini, A. franciscus possible synonyms); see taxonomy section.
| Question # | Short Name | Question Text | Response | Comments |
| 1 | Extinction risk | Current IUCN Red List category. [Data obtained from the IUCN Red List.] | Least Concern (LC) | Atelopus flavescens was evaluated by the IUCN in 2022 and will be listed as Least Concern when the report is published in 2023. It is also considered Least Concern by the National Red List French Guiana assessment (2018). |
| 2 | Possibly extinct | Is there a strong possibility that this species might be extinct in the wild? | No / unlikely | |
| 3 | Phylogenetic significance | The taxon’s Evolutionary Distinctiveness (ED) score, as generated by the ZSL EDGE program. (These data are not editable by Assessors). | ED value < 20 | |
| 4 | Protected habitat | Is a population of at least 50% of the individuals of the taxon included within a well-managed or reliably protected area or areas? | Yes / probably | The range of this species includes Mont Grand Matoury Nature Reserve, Kaw-Roura National Nature Reserve, and Trésor Regional National Reserve. If considering A. flavescens, A. barbotini, and A. franciscus as one species, its range also includes the following protected areas: Nouragues Natural Reserve, Guiana Amazonian Park/Parc Amazonien de Guyane, La Trinité National Nature Reserve, and Savane-Roche Virginie Inselberg. |
| 5 | Habitat for reintroduction, conservation translocation or supplementation | Does enough well-managed and reliably protected habitat exist, either within or outside of currently protected areas that is suitable for conservation translocation, including population restoration or conservation introduction? | Yes / probably | This species occurs in multiple national parks: Mont Grand Matoury Nature Reserve, Kaw-Roura National Nature Reserve, and Trésor Regional National Reserve. It occurs in additional protected areas if considering A. flavescens, A. barbotini, and A. franciscus as one species (Nouragues Natural Reserve, Guiana Amazonian National Park/Parc Amazonien de Guyane, La Trinité National Nature Reserve, Savane-Roche Virginie Inselberg, and Lucifer Dékou-Dékou Biological Reserve). |
| 6 | Previous reintroductions | Have reintroduction or translocation attempts been made in the past for this species? | No | |
| 7 | In situ conservation activities | Are any in situ conservation actions currently in place for this species? (Only required if a Red List Assessment has not been completed, or if new actions have been implemented since the last Red List Assessment. (Information from the Conservation Actions section of the Red List assessment should be reviewed and considered when answering this question.). | No / unlikely | Some current efforts include population surveys/inventories and a monitoring program in Mont Grand Matoury Nature Reserve. |
| 8 | In situ conservation activities | Are additional in situ conservation actions required to help conserve this species in the wild (e.g. habitat restoration and/or protection, control of invasive species, national legislation etc.)? | Yes / probably | More monitoring is needed; the state of different populations is currently unknown (although populations seem to have disappeared from some locations, such as from Montagne Favard; authors only found 5 individuals in 3 years at Montagne Sable). |
| 9 | In situ research | Is additional in situ research required to better understand the species, e.g. distribution, population trends, natural history etc.? | Yes | Field surveys are needed to understand distribution, population trends/status, phenology, and ecotypes. This species tested positive for Batrachochytrium dendrobatidis (Bd), with prevalence varying between 6.3-13.3% across three different sites (Matoury, Pararé and Saint-George; Courtois et al. 2015); however, the effect of Bd on population decline for this species remains unknown, so more sampling is needed. Research into impacts of climate change need to be assessed as well. |
| 10 | Threat mitigation | Are the threats facing the taxon, including any new and emerging threats not considered in the IUCN Red List, potentially reversible? | Threats are likely to be reversible in time frame to prevent further decline / extinction | Some illegal gold mining activity occurs both within and adjacent to protected areas. Gold mines, both legal and illegal, threaten the species via deforestation (habitat loss) and water pollution. Bd and climate change are potential threats. There may also be poaching/overcollection of this species--especially the yellow morph, which is likely gone in Montagne Favard inside Kaw Reserve since ~2012. Many individuals were collected in the 1980s, which could be an issue through today. More research needs to be conducted to better understand the scope of threats for this species. |
| 11 | Over-collection from the wild | Is the taxon suffering from collection within its natural range, either for food, for the pet trade or for any other reason, which threatens the species’ continued persistence in the wild? | No / unlikely | Although poaching is probably not affecting current populations, over-collection of this species likely occurs--especially the yellow morph, which is likely gone from Montagne Favard inside Kaw Reserve since ~2012 and from the adjacent Montagne Sable. Many individuals were collected in the 1980s; however, this is not likely to be a cause for decline today. |
| 12 | Population recovery | Is the known population of this species in the wild large enough to recover naturally, without ex situ intervention if threats are mitigated? | Yes / probably | There are likely enough individuals in the wild for the species to recover naturally, although this depends on the populations and the taxonomic definition (see taxonomy section). There are locations where populations have not been found anymore, such as Montagne Favard inside Kaw reserve (notably the one corresponding to the narrow definition of Atelopus flavescens); many areas have not been surveyed recently, so current population statuses are unclear. |
| 13 | Action plans | Does an Action Plan for the species already exist, or is one currently being developed? | No | A global action plan exists for the genus Atelopus, but not specifically for this species. |
| 14 | Biological distinctiveness | Does the taxon exhibit a distinctive reproductive mode, behaviour, aspect of morphology or physiology, within the Order to which it belongs (e.g. Anura, Passeriformes etc.)? | No aspect of biology known to be exceptional | |
| 15 | Cultural/socio-economic importance | Does the taxon have a special human cultural value (e.g. as a national or regional symbol, in a historic context, featuring in traditional stories) or economic value (e.g. food, traditional medicine, tourism) within its natural range or in a wider global context? | No | |
| 16 | Scientific importance | Is the species vital to current or planned research other than species-specific ecology/biology/conservation within the Order to which it belongs (e.g. Anura, Passeriformes etc.) e.g. human medicine, climate change, environmental pollutants and conservation science? | No research dependent on this species | |
| 17 | Ex situ research | Does conserving this species (or closely related species) in situ depend upon research that can be most easily carried out ex situ? | Yes | There are many potential ex situ studies that would help us better understand this and other Atelopus species in the wild, such as investigations regarding reproductive mode, resistance/susceptibility to chytridiomycosis and/or climate change (via physiology and responses to temperature changes). Studies on the hybridization of A. flavescens & A. hoogmoedi (and the resulting color morphs) could be useful, as this is not well understood in the wild. |
| 18 | Ex situ conservation activities | Is any ex situ research or other ex situ conservation action currently in place for this species? (Information from the Conservation Actions section of the Red List assessment should be reviewed and considered when answering this question.) | No / unlikely | |
| 19 | Husbandry analog required | If an ex situ rescue program is recommended for this species, would an analog species be required to develop husbandry protocols first? | No / unlikely | |
| 20 | Husbandry analog | Do the biological and ecological attributes of this species make it suitable for developing husbandry regimes for more threatened related species? i.e. could this species be used in captivity to help to develop husbandry and breeding protocols which could be used for a similar, but more endangered species at a later stage? | No | |
| 21 | Captive breeding | Has this species been successfully bred and/or maintained in captivity? | Maintained but no successful breeding | Currently, this species is being held in captivity through PLEEA (Plateforme d'étude experimental amazonienne), with the intention of breeding. However, the current program has 4 individuals (all of which are males), so breeding cannot commence until females are located (which is very difficult, as they do not typically occur near streams like males). Atelopus from the Nassau Mountains (which may be A. flavescens, but is considered A. hoogmoedi nassaui) have been successfully bred several times and to F2 generations at the Fragile Planet Wildlife Park in Texas, USA. However, given taxonomic uncertainty, this may not be A. flavescens. This species was also potentially (given taxonomic uncertainty) previously held in captivity in the Atlanta Botanical Garden (US; not successfully bred) and in the Cologne Zoo (Germany, see link: https://www.conservationevidence.com/individual-study/4899); however, in both instances, specimens came from Suriname, so it is unclear whether they were actually A. flavescens. A replicated study in 2008–2011 of captive harlequin toads Atelopus flavescens at Cologne Zoo, Germany (Gawor et al. 2012) found that egg deposition was stimulated by maintaining toads in a drier environment followed by a period of intensive irrigation. However, no toadlets survived past day 142. Three breeding trials resulted in no egg production. Following the simulation of a dry then wet season, two clutches of eggs were produced with 400–500 eggs (5–10% unfertilized). On day 43 after egg deposition, only two larvae survived. One tadpole survived to day 112, the other died as a froglet at day 142. Males were housed in three groups of 12–15 in tanks (100 x 60 x 60 cm) with artificial streams. Four females were transferred to the tanks for breeding. Tanks were misted several times each day. A dry season with reduced water and misting was then simulated for three months followed by a wet season with increased water and misting. |
| 22 | Conservation education/ecotourism potential | Is the species especially diurnal, active or colourful, or is there an interesting or unusual aspect of its ecology that make it particularly suitable to be an educational ambassador for conservation of the species in the range country, either in zoos or aquariums or within ecotourism activities? | Yes | This species is colorful, and occurs near cities, making it a suitable candidate for field trips/educational programs to see it in the wild. |
| 23 | Mandate | Is there an existing conservation mandate recommending the ex situ conservation of this taxon? | No | |
| 24 | Range State approval | If an ex situ initiative was proposed for this species, would it be supported (and approved) by the range State (either within the range State or out-of-country ex situ)? | Yes / probably | Authorization/approval from government exists to collect this species from the wild and translocate. |
| 25 | Founder specimens | Are sufficient animals of the taxon available or potentially available (from wild or captive sources) to initiate an ex situ program, if one was recommended? | Unknown | Research into availability of founders needs to be prioritised. Research into the availability of founders needs to be prioritized. The answer to this question largely depends on the ecotype (e.g., females of the yellow/pink belly morph are very difficult to find). |
| 26 | Taxonomic status | Has a complete taxonomic analysis of the species in the wild been carried out, to fully understand the functional unit you wish to conserve (i.e. have species limits been determined)? | No | Research into species validity needs to be prioritised. Research into species validity needs to be prioritized, especially considering contradictory accounts. A. flavescens could be part of a species complex; A. vermiculatus, A. fransiscus, and A. barbotini are possible synonyms. From Frost/Amphibian Species of the World: "Jorge, Ferrão, and Lima, 2020, Diversity, 12 (310): 7, presented phylogenetic evidence that Atelopus flavescens is imbedded within Atelopus hoogmoedi the implication being that Atelopus hoogmoedi is a species complex. Taucce, Costa-Campos, Carvalho, and Michalski, 2022, Eur. J. Taxon., 836: 96–130, regarded records of Atelopus flavescens from Amapá, Brazil, as only problematically assigned to Atelopus hoogmoedi." In the Jorge et al. 2020 paper, these Guiana Atelopus form 2 clades; in their phylogenetic tree there are 2 terminals labelled as hoogmoedi, forming the clade in which there is also franciscus and flavescens, so one can say that franciscus, barbotini and flavescens are embedded within hoogmoedi. However, both of the nested hoogmoedi are from central French Guiana, where a contact/hybrid zone occurs between hoogmoedi and flavescens (+barbotini and franciscus). Moreover, one of these hoogmoedi was in fact initially labelled as "spumarius" and considered as barbotini by Noonan and Gaucher 2005 and Loetters et al 2011; it is unclear why they changed it to hoogmoedi. Finally, none of these papers have topotypical material from the type locality of A. hoogmoedi. |
Citation:
Plewnia, A., Lorioux-Chevalier, U., Le Pape, T., Fouquet, A., & Lötters, S. 2023. Conservation Needs Assessment for Atelopus flavescens, French Guiana
(AArk/ASI Atelopus Assessment Workshop).
https://conservationneeds.org/assessment/6984
Accessed 27 Apr 2025
