The Flashlight Frog is a small bioluminescent frog, approximately 3-6 inches long, that lives in Cameroon, Africa. It was first mentioned by Karl Shuker, one of the thirteen founders of cryptozoology, in his 1997 book From Flying Toads to Snakes with Wings. It is mostly known from the fictional television show The Secret Saturdays and their franchise (cryptidsarereal.com). They have a horn on the tip of their snout that emits a red light that attracts insects. It also has a yellow, spiky tongue that is covered in deadly saliva.
Early in Karl Shuker's cryptozoological career it may have seemed that he was doing little more than plough furrows already well enough tilled by the discipline's founding father,
Bernard Heuvelmans. It's only comparatively recently that the sheer range of Shuker's interests and expertise have become apparent, and he has succeeded in placing himself apart from all the other monster-hunters and single-issue specialists who search for hidden animals.
Nowhere is his versatility better displayed than in this compilation of short articles, which discusses almost one hundred possible mystery animals without mentioning Bigfoot or the Loch Ness Monster once. Instead, Shuker concentrates rewardingly on the subject's marginalia, conjuring a dazzling array of maybe-animals that are almost always bizarre, and frequently zoologically impossible. From the water-rhinoceros of Lough Dubh to the vampire `death bird' of Ethiopia, and from the triple-headed river monsters of Bolivia to the white-furred elephantine sea serpent once washed ashore on the coast of South Africa, these are, for the most part, creatures that shouldn't exist - even though there's plenty of amusement value in supposing that they do.
Bioluminescence in Frogs
Bio-luminescence occurs in some lizards, but only in one known frog species, the green-boned glass frog in South America. There are many natural wonders in the animal
kingdom, perhaps none so unusual as the Glass Frog. This tiny frog gets its name because of the translucent skin on its underside (and in some species the top as well) that allows you to see its inner
organs, right down to its beating heart! Glass frogs, or centrolenids, are wide-skulled, long-limbed arboreal little frogs (SVL 20-60 mm) of Central and South American cloud and rain forests. Most lay eggs on vegetation overhanging water, or on rocks above the water surface. Their eyes are set on the tops of their heads, they have adhesive disks on their digit tips, and – while they are generally greenish on their dorsal surface – they derive their common name from the fact that they lack pigment on their ventral surface, meaning that their undersides are essentially transparent. I have
no idea why this is, and I’m not sure that anyone else does. Even stranger, most (perhaps all) species have green bones. Green bones. Their terminal phalanges are T-shaped (this is also the case in a few other neobatrachian groups, like poison-arrow frogs), the males of some species possess spines on their upper arms (these are used in territorial combat), and the two uniquely elongate ankle bones that characterize anurans (the tibiale and fibulare) are fused into a single element [adjacent image shows a species of Hyalinobatrachium: note the transparent ventral surface].
This isn’t a small or insignificant group: there are about 140 named species (a number that has increased from about 65 since the late 1980s), with multiple additional ones recognized but awaiting description (Cisneros-Heredia & McDiarmid 2006, pp. 12-13). Though often allied with hylids, data from mitochondrial DNA now indicates that glass frogs are more closely related to toads and leptodactylids sensu stricto (Darst & Cannatella 2004, Frost et al. 2006). It has also been suggested that glass frogs are the sister-taxon of Allophryne ruthveni (Austin et al. 2002), a controversial and problematical toothless hyloid that has often been given its own ‘family’, Allophrynidae (a second species of Allophryne has recently been discovered, but I don’t think it’s been published yet. Please let me know if you know otherwise).