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Description
The upper levels of the largest body of water of Mapple White tepui hosts a diverse fauna, including particularly large, unique creatures. The False leatherback (Ophiochelys copii) undoubtedly constitutes one of its most impressive and iconic members. Despite sporting a "leathery" and partly carved out shell structure as in trionychids, as well as sea turtle-like fins somewhat reminiscent of the australian pig-nosed turtle (Carettochelys insculpta), this creature is, like all the South American freshwater turtles, a pleurodire (side necked turtles), instead of a cryptodire. Its resemblance to several cryptodiran species is as such the result of evolutionary convergence. Phylogenetic analysis would show that False leatherback nearest cousin are the turtles from the Hydromedusa genus, which it would have diverged with during the early cretaceous. The longest recorded individuals from tail to head can go as far as 2.3m, and a shell discovered by early century explorers in a pleistocene Jmu midden is estimated to have belonged to a three meters long individual (Stümpke et al, 1943). The false leatherback is a notorious swift hunter and efficient diver, showing evidence of mesothermy and unusually active lifestyle, pursuing its preys through the deep ends of the tepui's large cave system and capturing them through a combination of side-stabbing motion and suction similarly to its distant Hydromedusa cousins. Recovered material from the stomach of a few stranded individuals show evidence of predation on small birds, rodents and even terrestrial hoatzins chicks (Odulob, 1973).

Far below a certain number of troglobite representatives are to be found. The blind Mapple White angelfish (Pterophyllum challengeri) is a beautiful yet dreary-looking example of this fauna, and the eyeless, pink-transparent derivative of its well known Orinoco cousins are unfortunately under threat due to the high demand by aquarists worldwide, encouraging poaching pressure in the central lake. The Mapple White cave squat lobster (Aegla septentrionalis) isn't in itself particularly impressive - four other cave-dwelling members of the Aegla genus are known from southern Brazil - but they constitute the northernmost known species of this genus known to science, and how exactly did it ended here remains somewhat of a mystery.

Most impressive and still poorly understood though remains the presence of a few remarkable endemic species of eel-like fishes from the family Apteronotidae, commonly referred as "ghost knifefishes", and typically subservient to the deepest parts of the Amazon river-system. Known for generating weak electric fields and for their many functional convergences with cave fishes (blindness or complete absence of eyes, total depigmentation and so on), those fishes are also present in the cave system of the tepui, and clearly took advantage on an environment already quite suitable to them ; adding perhaps a relative lack of oxygen and current compared to their original habitat. The about 15cm long Mapple White knifefish (Troglostermarchus pseudocyena) constitutes a typical example, although it is estimated that dozen of species from this group are yet to be described among the deepest reaches of the tepui.

But the unconditionally most derived and popular member of the Mapple White knifefishes undoubtedly remains the stalking knifefish (Compsaraia graucocutis). Contrary to its amazonian counterparts, it sports visible eyes and decent vision, an ash-colored, thick layer of skin, and remains much of its time floating over the surface, whereas its young typically look like and live like other members of its genus. A fairly large (about 1m30) fish, it rests during the day under the bromeliad, orchidea and Bonnetia gardens for an unsuspecting prey ; typically confounding itself with the interlacing driftwood and floating soil and refuse which accumulates on the lake borders, under the "hanging gardens" . When an unsuspecting animal approaches ; typically a small bird, rodent, lizard or particularly large insect - the fish snatches it in a sudden forward motion. The particularly long-faced males are often seen violently battling at the surface by the end of the year.

Description
The upper levels of the largest body of water of Mapple White tepui hosts a diverse fauna, including particularly large, unique creatures. The False leatherback (Ophiochelys copii) undoubtedly constitutes one of its most impressive and iconic members. Despite sporting a "leathery" and partly carved out shell structure as in trionychids, as well as sea turtle-like fins somewhat reminiscent of the australian pig-nosed turtle (Carettochelys insculpta), this creature is, like all the South American freshwater turtles, a pleurodire (side necked turtles), instead of a cryptodire. Its resemblance to several cryptodiran species is as such the result of evolutionary convergence. Phylogenetic analysis would show that False leatherback nearest cousin are the turtles from the Hydromedusa genus, which it would have diverged with during the early cretaceous. The longest recorded individuals from tail to head can go as far as 2.3m, and a shell discovered by early century explorers in a pleistocene Jmu midden is estimated to have belonged to a three meters long individual (Stümpke et al, 1943). The false leatherback is a notorious swift hunter and efficient diver, showing evidence of mesothermy and unusually active lifestyle, pursuing its preys through the deep ends of the tepui's large cave system and capturing them through a combination of side-stabbing motion and suction similarly to its distant Hydromedusa cousins. Recovered material from the stomach of a few stranded individuals show evidence of predation on small birds, rodents and even terrestrial hoatzins chicks (Odulob, 1973).

Far below a certain number of troglobite representatives are to be found. The blind Mapple White angelfish (Pterophyllum challengeri) is a beautiful yet dreary-looking example of this fauna, and the eyeless, pink-transparent derivative of its well known Orinoco cousins are unfortunately under threat due to the high demand by aquarists worldwide, encouraging poaching pressure in the central lake. The Mapple White cave squat lobster (Aegla septentrionalis) isn't in itself particularly impressive - four other cave-dwelling members of the Aegla genus are known from southern Brazil - but they constitute the northernmost known species of this genus known to science, and how exactly did it ended here remains somewhat of a mystery.

Most impressive and still poorly understood though remains the presence of a few remarkable endemic species of eel-like fishes from the family Apteronotidae, commonly referred as "ghost knifefishes", and typically subservient to the deepest parts of the Amazon river-system. Known for generating weak electric fields and for their many functional convergences with cave fishes (blindness or complete absence of eyes, total depigmentation and so on), those fishes are also present in the cave system of the tepui, and clearly took advantage on an environment already quite suitable to them ; adding perhaps a relative lack of oxygen and current compared to their original habitat. The about 15cm long Mapple White knifefish (Troglostermarchus pseudocyena) constitutes a typical example, although it is estimated that dozen of species from this group are yet to be described among the deepest reaches of the tepui.

But the unconditionally most derived and popular member of the Mapple White knifefishes undoubtedly remains the stalking knifefish (Compsaraia graucocutis). Contrary to its amazonian counterparts, it sports visible eyes and decent vision, an ash-colored, thick layer of skin, and remains much of its time floating over the surface, whereas its young typically look like and live like other members of its genus. A fairly large (about 1m30) fish, it rests during the day under the bromeliad, orchidea and Bonnetia gardens for an unsuspecting prey ; typically confounding itself with the interlacing driftwood and floating soil and refuse which accumulates on the lake borders, under the "hanging gardens" . When an unsuspecting animal approaches ; typically a small bird, rodent, lizard or particularly large insect - the fish snatches it in a sudden forward motion. The particularly long-faced males are often seen violently battling at the surface by the end of the year.