text: ecnomiohyla rabborum ecnomiohyla rabborum , commonly known as ' fringe - limbed treefrog , is a species of frogs in the family hylidae . they are relatively large frogs inhabiting the forest canopies of central panama . like other members of the genus ecnomiohyla , they are capable of gliding by spreading their enormous and fully webbed hands and feet during descent . the males of the species are highly territorial , guarding water - filled tree holes used for breeding . they are also the ones responsible for guarding and caring for the young , including providing food . they are the only known species of frog where the tadpoles derive nutrition by feeding on the skin cells of their fathers . the species was originally discovered in 2005 and formally described in 2008 by a team of herpetologists led by joseph r. mendelson iii . it is named in honor of the conservationists and herpetologists george b. rabb and mary s. rabb . it is officially listed as critically endangered by the international union for conservation of nature and natural resources ( iucn ) as of 2009 . it is believed that the species may be extinct in the wild due to the epidemic of batrachochytrium dendrobatidis in its native range . despite the efforts of several conservation teams , captive breeding programs have all failed . the last known female of the species died in 2009 . it was survived by two other individuals , both males . on february 17 , 2012 , one of the two was euthanized at zoo atlanta in georgia due to failing health . the last known surviving member of the species , an adult male named , currently resides at the atlanta botanical garden . description ecnomiohyla rabborum is a relatively large frog . the snout - vent length ( svl ) of males average between 62 to 97 mm ( 2 . 4 to 3 . 8 in ) , while in females it is between 61 to 100 mm ( 2 . 4 to 3 . 9 in ) . the head is wider than the body and flattened at the top . the snout is moderately long with nostrils protruding from the sides near the tip . viewed from the top , the snout is more or less elliptical in shape . the ridge is concave ( curves outward ) and has thick and rounded edges . the loreal regions are similarly concave . the tympana are smaller in diameter than the eyes and slightly inclined . smooth glandular structures ( known as the fold ) extend over the tympana from the eyes to the edges of the lower jaw . the tongue is round and it possesses narrowly spaced ovoid groups of pre - vomerine teeth . the arms are short and stout with very large hands . there are no skin folds on the wrists , though a scalloped fringe of skin is present from the elbows to just below the discs on the fourth fingers . the fingers are all relatively short with large flattened discs on the tips . the discs on the second , third , and fourth fingers are about the same diameter as the tympana . small protrusions known as tubercles are present on the underside of the hands . on the first finger , the tubercles on the tipmost joints are elliptical in shape . on the second and third fingers , the tubercles below the finger joints ( tubercles ) are smaller than that on the fourth fingers . there are no tubercles on the palms of the hands though elongated flat tubercles are present behind the bases of the inner fingers ( the " thumbs " ) . numerous small and round tubercles are also present in between the joints of the fingers . the fingers are more or less fully webbed . the hind limbs are slender and of moderate length . like the hands , the feet are very large . when resting , the heels of the legs barely overlap each other . if stretched forward up the length of the body , the articulation ( the " ankle " ) reaches beyond the eyes . like the arms , a fringe of scalloped skin also extends from the heel to the base of the foot on each leg , continuing as a low ridge to the base of the disc of the fifth toe . the toes , like the fingers , possess flattened discs at the tips , though they are slightly smaller in diameter . the tubercles on the tipmost joints of the fifth toes are larger than all of the other tubercles on the toes . interspersed between them are numerous small and conical tubercles . the toes are also fully webbed . the skin of e. rabborum is granular in texture and predominantly a mottled brown . the upper surfaces of the limbs are also mottled brown while the rear surfaces of the thighs are a pale yellow . the chin and upper chest are distinctively brown , though the rest of the underside of the body is mostly white speckled with irregular brown spots . the eyelids and upper surfaces of the limbs and back are studded with green flecks , the appearance and positions of which can be changed by the animal voluntarily ( metachrosis ) . the irises of the eyes are uniformly reddish - brown . during the breeding season , adult males of the species are characterized by greatly enlarged upper arms ( humerus ) with a bony ridge covered by skin and black keratinized spines . spines are also present on the upper surface of the area just before the thumbs . these spines are likely used during amplexus . taxonomy ecnomiohyla rabborum is classified under the genus ecnomiohyla of the treefrog subfamily , family hylidae . it was first described in 2008 by a team of herpetologists consisting of joseph r. mendelson iii , jay m. savage , edgardo griffith , heidi ross , brian kubicki , and ronald . during its discovery in 2005 , it was initially misidentified by the team as ecnomiohyla , but kubicki recognized it as a new species . the type specimens were raised in captivity . they were obtained from tadpoles collected by griffith and ross from an area near el valle de antón , , panama on july 15 , 2005 . the generic name ecnomiohyla comes from greek ( " marvelous " or " unusual " ) and , the companion of hercules . the specific name is in honor of the conservationists and herpetologists george b. rabb and mary s. rabb . distribution ecnomiohyla rabborum is known only from the cloud forests of the pacific - facing slopes of the mountains above the town of el valle de antón in central panama , between the provinces of and panamá . its range has an area of less than 100 km2 ( 39 sq mi ) at altitudes of 900 to 1 , 150 m ( 2 , 950 to 3 , 770 ft ) . however , it has not been observed in the area since 2007 . ecology and biology ecnomiohyla rabborum , like other members of the genus , live in the forest canopy . they are nocturnal and feed on insects . when threatened , they are capable of gliding through the air by leaping from their perch and fully stretching their massive webbed hands and feet . they can also steer the direction of their descent . in observations , they have been known to glide for a distance of 9 m ( 30 ft ) . the males of the species are highly territorial , defending water - filled tree holes used for breeding . the advertising calls of e. rabborum males consist of " warm up " owl - like calls of three to five notes immediately followed by a single " " . the calling bouts happen only at night and last for about one to two minutes , with the intervals longer at the beginning and gradually becoming shorter . aside from attracting females , the calls may also serve to warn off competing males . mating occurs throughout the year , though the calls seem to intensify two to three days before or after a full moon and during the peak mating season from mid - march to may . females lay their eggs inside the water - filled tree holes , attached to the wood or bark just above the waterline . after laying their eggs , the females leave while the males remain to guard them . males may mate more than once and a single tree hole can contain an egg clutch of 60 to 200 eggs . the eggs hatch into large tadpoles with dorsoventrally flattened bodies and short , blunt snouts . the eyes are situated on top and directed towards the sides . they are not visible when the tadpole is viewed from below . the nostrils are situated about two thirds of the way between the eyes and snout . the mouth is small and located at the bottom of the tip of the snout . small papillae are present along the sides of the upper lip and along the entire margin of the lower lip . the beaks are robust and with small serrations . the spiracle opens on the middle of the left side of the body . the tail is slender with fins that do not extend to the body . the tadpoles are predominantly pale brown in color . at the time when the legs first appear , they have a snout to vent length of roughly 25 to 27 mm ( 0 . 98 to 1 . 06 in ) . the tadpoles are so large and numerous that at times , there appear to be more tadpoles than water in the tree holes . e. rabborum is remarkable in that the males appear to provide nutrition to the tadpoles directly . during the day , the males back into the tadpole - filled water of the tree holes and remain in that half - submerged state until night . during this time , the tadpoles swim around them , rasping small pieces of skin from their fathers ' backs and eating them . this is the first observed instance of any frog species doing this , though it is similar to the way some female caecilians feed their young . conservation at the time of its collection , the herpetologists who later described ecnomiohyla rabborum were already aware of the encroaching threat of the chytrid fungus batrachochytrium dendrobatidis ( colloquially referred to by biologists as " " ) in panama . the fungus causes an infectious amphibian disease called chytridiomycosis , which has been linked to the massive decline and extinction of amphibian species in certain parts of the world ; including the americas , australia , and new zealand . infected amphibians can display a wide variety of symptoms , usually including lethargic and abnormal behavior , convulsions , peeling skin , ulcers , and hemorrhaging ; eventually resulting in death . the origin of the disease is unknown , but there is speculation that it may have been introduced throughout the world via importation of the african clawed frog ( xenopus laevis ) . in 2006 , in the hopes of saving the species , the then undescribed specimens of e. rabborum that teams of herpetologists collected were sent to captive breeding facilities in the el valle amphibian conservation centre ( ) , zoo atlanta , and the atlanta botanical garden . however , these efforts ultimately proved to be futile . the frogs thrived in these facilities but never mated . the last female died in 2009 in the atlanta botanical garden . in an essay regarding the rapid extinctions of amphibians happening around the world , joseph r. mendelson iii , the curator of in zoo atlanta and one of the scientists who first described e. rabborum , stated that herpetologists in the last 20 years are becoming " forensic taxonomists " . species are now being described just before or even after they have already gone extinct . on the situation of e. rabborum , he comments : it appears that nature has run its course before three teams of dedicated people were able to determine the needs of these frogs in order for them to reproduce . to have been a part of one of those teams has been a frustrating and sad experience . two males in zoo atlanta and atlanta botanical garden survived until february 17 , 2012 , when one of them had to be euthanized to prevent suffering after a decline in health and to preserve valuable genetic material . though the frog could have been allowed to die naturally , amphibians decompose rapidly . if it had died during the night when no personnel were present , it could have proven impossible to extract genetic material . the deputy director of the zoo , dwight lawson commented : this is the second time in my career that i have literally seen one of the very last of its kind die and an entire species disappear forever with it . it is a disturbing experience , and we are all poorer for it . the ongoing amphibian extinction crisis has taken a rich diversity of animals from us , and more effort and resources are desperately needed to halt the losses . the last known observation of the frog in the wild was that of a single male heard calling ( but not seen ) in 2007 . at the time of its last survey in 2009 , the iucn classified e. rabborum as critically endangered . more recent estimates deem the species effectively extinct in the wild . a single adult male named at the atlanta botanical garden is the last known survivor of the species .