|Scientific Name:||Excidobates captivus|
|Species Authority:||(Myers, 1982)|
Adelphobates captivus (Myers, 1982)
Dendrobates captivus Myers, 1982
|Taxonomic Notes:||This species was originally described as Dendrobates captivus (Myers 1982) and included in the genus Adelphobates by Grant et al. 2006.|
|Red List Category & Criteria:||Least Concern ver 3.1|
|Assessor/s:||IUCN SSC Amphibian Specialist Group|
|Contributor/s:||Angulo, A., Twomey, E., Icochea M., J. & Jungfer, K.|
Listed as Least Concern in view of its supposed wide distribution, with a high likelihood of occurring still more widely, presumed large population, and occurrence in habitats that are not significantly threatened.
This species occurs in northwestern Peru, where it is known only from the lowland valley formed between the Cordillera del Condor and the Cerros de Campanquis, and from southern Ecuador, near Panguintza, at approximately 800 m asl (Twomey and Brown 2008; E. Twomey pers. comm. August 2011). The type series collected in 1929 and the majority of the specimens found in 2006 come from the same area, the south bank of the Río Marañón at the mouth of the Río Santiago in Amazonian Peru (Twomey and Brown 2008). Only a single individual was found in the north bank of the Marañón east of Río Santiago (Twomey and Brown 2008). This species is believed to be restricted to that region where it occurs from approximately 177 to 400 m asl, but it also could possibly occur at higher elevations in the Cordillera del Condor as a population of this species was reported from that area (20 km northeast of Santa Rosa) by Mark Pepper in 2007 (Twomey and Brown 2008). Further survey efforts in suitable neighbouring areas like the north side of the Marañón along both east and west banks of the Santiago, the Cerros de Campanquis and the west bank of the Santiago 8 km from its junction with the Marañón were unsuccessful in finding this species (Twomey and Brown 2008). In addition, another survey in the Cerros de Campanquis carried out by the Field Museum around September 2011 did not find this species (E. Twomey pers. comm. March 2013). Its range, taken as a proxy for extent of occurrence (EOO), is estimated to be approximately 7,352 km²; however, this species is presumed to occur more widely across the Río Santiago valley and it could occur over an area of up to 14,000 km² (E. Twomey pers. comm. August 2011).
Native:Ecuador (Ecuador (mainland)); Peru
|Range Map:||Click here to open the map viewer and explore range.|
It had not been seen alive since 1929 (Myers 1982), until 17 individuals were found during an expedition to its type locality in 2006. The valley’s inaccessible nature (this valley is only accessible from the east, by river via the Pongo de Manseriche a gorge that constricts the 750 m-wide Marañón to a 120 m-wide rapid) and dangerous indigenous unrest (the Santiago valley is inhabited by Huambisa and Aguaruna natives, who, until recently, engaged in regular intertribal combat) prohibited exploration for 77 years before this first known herpetological survey of this region in 2006 (Twomey and Brown 2008), which reported the presence of this species from the Rio Marañón's banks. This frog is common within its known distribution range and was it found in high densities in only two small areas of the Santiago valley (17 individuals observed over 40 person/days as reported in von May et al. 2008; E. Twomey pers. comm. August 2011). This suggests that this species may be continuously distributed in seemingly homogeneous lowland habitat (E. Twomey pers. comm. August 2011). There is insufficient information available to determine whether there has been a population decline in this species (E. Twomey pers. comm. March 2013).
|Habitat and Ecology:||It is a diurnal species of lowland tropical moist forest (Twomey and Brown et al. 2008). Individuals were found either in low-lying parts of the forest or in forest adjacent to streams (Twomey and Brown et al. 2008). These streamside habitats are characterized by abundant Heliconia, which appears to be an important breeding site for this species as four tadpole-carrying males were found in or near Heliconia, suggesting these plants are used for tadpole deposition (Twomey and Brown et al. 2008). Frogs not found directly in phytotelmata (water bodies held by plants) were usually on the ground, suggesting that this species is at least partly terrestrial. Egg deposition may also be terrestrial, as an adult pair was observed for several minutes courting in the leaf litter (Twomey and Brown et al. 2008). This species has been only found within intact forest and it is unknown whether it might be able to tolerate any degree of habitat degradation (E. Twomey pers. comm. August 2011).|
There has been illegal gold mining in the Santiago valley but it is unknown how this minor threat might affect the species (E. Twomey pers. comm. August 2011, March 2013). Chytrid (Batrachochytrium dendrobatidis) tests were consistently negative for adults and tadpoles although due to the small sample size this will need further verification (Twomey and Brown et al. 2008). No further investigations into the presence of chytrid have been carried out since 2008 (E. Twomey pers. comm. March 2013).
This species may possibly occur within the Santiago-Comaina Reserve as it was found in close vicinity to this protected area (E. Twomey pers. comm August 2011). However, it has not been found in this reserve so far (E. Twomey pers. comm. March 2013). More research is needed on this species' distribution, population trends and threats.
|Citation:||IUCN SSC Amphibian Specialist Group 2013. Excidobates captivus. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.2. <www.iucnredlist.org>. Downloaded on 23 April 2014.|