The one question in cryptozoology that has always drawn attention is how could a large creature remain undiscovered and unphotographed to remain an enigma? It seems in this day and age in which we have mapped and explored every corner of our planet that this simply could not be, yet there are many precedents to make a case for an animal remaining hidden from us. Here we will look at a selection of some of the most elusive and poorly understood species there are, some of which have barely ever been seen at all, and which show that there are still surprises waiting for us out in the wildernesses of the world.
One might not think that there could be a big cat out there that isn’t well-documented and well-studied, but this turns out to not be the case at all. A wild cat endemic to the rainforests of West and Central Africa, the African golden cat is about twice the size of a normal housecoat and slightly smaller than an American bobcat, with a fur color ranging from chestnut or reddish-brown, greyish brown to dark slaty and sometimes spotted in a way reminiscent of a leopard. It inhabits tropical forests from Senegal to the Central African Republic, Kenya and as far south as northern Angola, with its main stronghold said to be in the forests of the Congo Basin, but that is about all we really know because barely anyone has ever even seen these creatures in the wild.
Although it was first described in 1827 and has long been known to exist out in the wilds, the golden cat is so extremely reclusive that little is known of its habits or lifestyle, and it was not even photographed in the wild until 2002, and it was not videotaped until about a decade after that, in 2011. It is considered to be one of the least studied and most mysterious felines in the world, and there are wildlife researchers out in the middle of golden cat habitat who have spent years in the most remote reaches looking for it and never even seen one in the flesh, with one researcher dedicated to studying the species having only ever seen one once in four years of tracking it down. In recent years, camera trap technology has helped to capture more images of the elusive creatures, but there are only a few hundred images and partial images of the cats out of around 20,000 traps set out to document them, making it hard to determine just how many of them may be out there and impossible to properly assign an endangered species classification to them. Cat researcher David Mills has said of his quest to document the species:
Having long been interested in wild cats, and Africa, it was incredible to me that there was an almost unknown species waiting to be studied. What’s more, this is a species living within an area, and habitat, that is suffering extensive threats from people. So it was the combination of lack of knowledge, and growing threat, that first inspired me to study the golden cat. Golden cats were one of those neglected species. Their habitat and the extreme rarity of sightings seemed to discourage people from studying them… and I love cats and the rainforest, so it seemed like an obvious choice.
Just as interesting is another large mammal that long lived within the remote forests of Vietnam without anyone ever realizing it was there at all. So elusive that it is often called the “Asian Unicorn,” the saola is a large, horned, forest-dwelling bovine native to the Annamite Range in Vietnam and Laos, and which was only first described in 1992, when a set of remains was found in Vũ Quang National Park in the form of a skull featuring a pair of strange, long and pointed horns received from a local hunter who found it lying around. No one had ever seen whatever this creature had been, with not even the locals seeming to be particularly familiar with it, and it was not until the following year that an actual photograph was taken of the mysterious creature. Two specimens were eventually captured but died not long after, and the new species was widely thought to be extinct in the wild until in 2013 a camera trap got another photograph of one in the wild. Although the area is remote and has turned up many new species, the saola was the first large mammal to be discovered in the area for 50 years. The saola has been said to have one of the smallest ranges of any large land mammal, and although it is considered to be critically endangered, no one has any idea of how many of them there actually are. Indeed, not much is known about anything about them, including their dietary and reproductive habits, and the saola is considered to be one of the least understood large mammals in the world, with researchers spending their whole careers looking for one without ever seeing one.
Not quite as large but every bit as enigmatic is the red-crested tree-rat, or Santa Marta toro, which is a species of tree-rat native to the wild jungles of Colombia, in South America. Measuring between 51 cm (20 in) from head to the tip of their tail, with their tails measuring between 18 and 28 cm (7.1 and 11.0 in), the red-crested street rat is known for its intense red coloring along its back, at least for those who have actually ever seen one, which is few. The species was first described from a lone specimen collected in 1898 in Sierra Nevada de Santa Marta, after which the animal has only been known from a total of three actual specimens ever collected, and it was only first photographed in the wild in 2011. After this, it has remained elusive and no one knows much about them or whether they are still around at all.
There have been some very mysterious birds to add to these ranks as well. In the rainforests of the country of Madagascar there is a very elusive large bird of prey called the Madagascar serpent eagle. It was long thought to be extinct from all the way up into the 1990s, when a nest was found on the Masoala Peninsula. After that all we have to go on are sightings and trace signs of the raptors, and it has managed to elude being photographed. It is probably the most elusive and least understood bird of prey in the world, and the only thing we have to know that it even still exists or not are some sittings reports and occasional nests.
Another bird that is practically unknown to us is what is known as the night parrot, of the deserts of western Australia and Queensland. Although once thought to be common, the species of parrot suddenly just seems to have vanished from the face of the earth for reasons not yet fully understood. There were then uncorroborated sporadic sightings over the birds over the years, but there were no actual documented sightings of the night parrot from between 1912 and 1979, when ornithologist Shane Parker from the South Australian Museum spotted an apparent flock of the birds in the far north of South Australia. After that, the night parrot again disappeared until 1990, when a pair of ornithologists just happened to stumble across a dead night parrot along a desolate highway in the Australian wilderness and proved that it still lived out there somewhere. Sightings of the birds since then have been extremely rare, but on April 4, 2015, ornithologists Steve Murphy and Rachel Barr hit the Holy Grail when they captured and radio tagged a live individual, whom they nicknamed "Pedro", in southwestern Queensland, although its location has been kept secret. Other than that, night parrots are mostly known from the odd feather or camera trap photo, and the night parrot is considered to be one of the most elusive and mysterious birds in the world.
Equally bizarre and enigmatic is the story of the bird species that is known tenuously through only a single wing. In 1990, researchers in Nechisar National Park, Ethiopia, discovered a dead, decomposing bird they could not identify by a roadside that they surmised had been killed by a passing car. The body of the bird was too badly decomposed to be of much use, so they removed one of its wings and sent it to the Natural History Museum in London, after which it was found to be a new species based on its unique coloration and came to be known as the Nechisar nightjar. It was an unusual way to identify a new species, a situation reflected even its scientific name, Caprimulgus solala, with the word “solala” meaning “only a wing.”
Although the species' status is unknown, the Nechisar nightjar has been tentatively designated as “vulnerable” until more information is forthcoming. In the meantime, it has become a sort of Holy Grail for birdwatchers and ornithologists, who have traveled to the region in which the wing was found looking for further evidence of its owner's existence. There have been a few reported sightings of a bird that could be the Nechisar nightjar, as well as a few blurry purported photos of it, but these have remained inconclusive and the species continues to be a phantom known from a mere single, solitary wing forgotten upon a remote roadside.
Even rarer than any of these species we have looked at are those that have never been seen alive at all, but are rather only known from a single specimen. One species of mammal known from only a single specimen is the dusky flying fox (Pteropus brunneus), also known as the Percy Island flying fox. This species is known from a single individual collected in 1874 in the Percy Island group off Queensland, Australia, and no further examples have ever been found. Although only the one sole specimen exists, now mounted at the British Museum, reports from colonists of the islands in the 19th century suggest that the species was once rather plentiful on the islands, and it was widely sighted even after it was officially discovered, although no further specimens were provided. The species has nevertheless remained a specter, with no further specimens ever found in its supposed habitat, and confounding all further attempts to locate it, leading for some scientists to suggest that the one collected specimen was perhaps a wayward individual originating from somewhere else, such as the Solomon Islands or the Louisiade Archipelago. It has also been speculated that the found specimen was perhaps merely an aberrant individual of a known species. Intriguingly, there were reports of a potential relic colony of the mysterious flying foxes sighted on Akens Island in the 1990s, but an investigation of the reports turned up no new specimens or even any sign of them. At present, the dusky flying fox is considered to be very likely extinct.
From the wilds of Ethiopia comes another enigmatic mammal known from a single lone specimen. The Ethiopian water mouse (Nilopegamys plumbeus), also known rather unappetizingly as the Ethiopian amphibious rat, is a highly water adapted rodent that is known from a single individual caught in a trap near the source of the Little Abbai River, at Gojjam, in north western Ethiopia in the 1920s. Further surveys of the area to locate and collect more of the species have failed to find any trace of them. Considering that the habitat where the type specimen was originally found had already been severely degraded by rapidly expanding pastureland for grazing cattle at the time, and is almost completely destroyed by such practices at present, the Ethiopian water mouse is most certainly gone forever, leaving us with only a single individual to truly decipher its natural history.
Some species of new mammal have been not only been identified from a single specimen, but also one that wasn’t even fully intact. One example is Sir David’s long-beaked echidna (Zaglossus attenboroughi), also known as Attenborough’s long-beaked echidna or the Cyclops long-beaked echidna, and named after none other than famous British naturalist Sir David Attenborough himself. The species is known from only a single specimen that was found in a badly damaged state in a remote area of New Guinea’s Cyclops Mountains in 1961 by Dutch explorers. This species is notable for being the smallest species of echidna.
There have been several attempts to locate more surviving specimens of Sir David’s long-beaked echidna since its discovery, most notably in 2007, when a team of researchers found promising evidence of the creatures in the form of distinct feeding holes and fresh tracks, but a thorough search of the area turned up no new specimens of the new echidna or even a sighting of one. Even so, local hunters of the area claim that the creature is around and often hunted, giving hope to conservationists that the species, although highly elusive, is perhaps not extinct, nor even as threatened as its current status would suggest. The one lone specimen of Sir David’s long-beaked echidna is mounted at the Leiden Natural History Museum in the Netherlands.
Recognized by even more tenuous physical evidence is the Somali Golden Mole (Calcochloris tytonis), a type of golden mole from the troubled African nation of Somalia. This particular species is known from only a single partial jawbone and some ear bones found in an owl pellet in 1964. Despite this very partial specimen, upon analysis the bones were deemed unique enough to classify it as a new species, although no further representatives of the species have ever been found. Interestingly, another species of golden mole, which in fact are only very distantly related to true moles, has also been classified based on one specimen as well. In 1950, an estate owner in Gouna, South Africa, found a single individual of a new type of golden mole that would go on to be called Visagie’s golden mole (Chrysochloris visagiei). There have been follow-up expeditions to the area to look for further specimens, but none have ever been found.
Also a species known from only a partial specimen is the small Samoan flying fox (Pteropus allenorum). The only known remains of this species were a broken skull and damaged skin collected in 1856 on the island of Upolu, Western Samoa, West Polynesia, by an H.C. Caldwell. These remains were then stored away at the Academy of Natural Sciences of Philadelphia until 2006, when they were accidentally found collecting dust in the basement and a researcher was astute enough to look into them further. Although found in 1856, it would not be until 2009 that it would be recognized as a new species, and is still only known from a poorly preserved skin and a partial skull. It is thought that this species is likely now extinct, as no further animals have ever been located despite extensive searches.
One of the most mysterious discoveries of a new bird species based on one specimen is that of the striking Liverpool pigeon (Caloenas maculate). The specimen was originally acquired by the 13th Earl of Derby, who added it to his vast collection of assorted birds and other animals, and here is where it long remained forgotten and lost amongst a myriad of other specimens at Knowsley Hall in Merseyside. The collection went to the Liverpool World Museum upon the Earl’s death in 1851 and the pigeon was discovered by pure chance, a mystifying lone specimen with no label or information attached to it as to when or where it was originally collected. The puzzling specimen, which is characterized by very small, practically useless wings and striking spotted green coloration, has been theorized as possibly having its origins somewhere in French Polynesia, which was popular with animal collectors at the time and some of the other animals in the Earl’s collection were from there. Other than that, the Liverpool pigeon remains a complete and total mystery.
Almost as mysterious as the tale of the Liverpool pigeon is that of a bird that was shot in 1825 by naturalist Andrew Bloxam while on an expedition to the island of Mauke, in the Cook Islands, which lie in the South Pacific northeast of New Zealand, between French Polynesia and American Samoa. The bird in question was a new type of starling, and its well preserved skin eventually wound up at the Natural History Museum in London, where it was discovered and found to be simply labelled “12.192,” with no other information as to when or where it had been gathered, leading to its nickname “the mysterious starling.” For years no one could figure out what this species was or where it came from, and it was often misidentified or mislabeled, further adding to the air of mystery and confusion surrounding it. Mauke was not visited for serious investigation by ornithologists until 1973, and by that time the bird was apparently long extinct, likely due to the infestation of a very large variety of rats. This prevented the collection of any other new specimens of whatever the bird was, and further created an obstacle to positively identifying it. It was not until 1986 that its true origins were revealed by research and study of entries from Bloxam’s original diary and field notes done by the American ornithologist Storrs Olson, and it was finally truly recognized as a new species after over 150 years of obscurity. In a strange twist, it was also found that Bloxam had apparently shot some sort of unknown pigeon on the same trip to Mauke, and although this actual physical specimen was never found among the collections, it is speculated it may have been the only known example of the now extinct Mauke fruit dove.
Reptiles are not exempt from single-holotype species like these either. In fact, the largest known species of gecko in the world is known from only one taxidermy specimen that is not even complete. The mounted specimen was first noticed in 1979 by herpetologist Alain Delcourt among a collection at the Marseille Museum of Natural History in France, and recognized as unique among geckos due to its coloration and impressive size. Efforts to identify the unusual creature were hampered by the fact that there was no information on where or when the specimen had been collected and no label, although it was surmised that it had probably been captured sometime between the years of 1833 and 1869 and likely had its origins somewhere in the Pacific. Other than that, the specimen long remained a perplexing enigma. Researchers would later discover that the mounted gecko was similar in appearance to reports from New Zealand of a creature known locally as the kawekaweau, which was said to be a massive, rusty brown gecko with reddish stripes that was claimed to be around 62 centimeters (2 feet) long and “as thick as a man’s wrist.” There are some scattered accounts of early European explorers of New Zealand coming across mysterious large lizards which could have been the kawekaweau, and there is one record from 1870 of a Maori chief who saw a gecko that exactly matches the description of the museum specimen and killed it in the forests of the Waimana Valley, making it the only known detailed, documented sighting of one of the animals alive.
Based on this account and the similarities to the mounted gecko specimen, Delacourt and other respected researchers came to the conclusion that they were one and the same species. In 1986, the kawekaweau, now more formally known as Delacourt’s sticky-toed gecko or Delacourt’s giant gecko (Hoplodactylus delcourti), was named a new species solely based on this single mysterious museum mount. This large gecko can reach sizes of up to 2 feet long; nearly twice as large as the next largest gecko, the New Caledonian giant forest gecko, which can get up to 36 centimeters (14 inches) in length. Unfortunately, like many of the animals we’ve been investigating here, the Delacourt’s giant gecko is considered to be most likely extinct, and the species remain wrapped in mystery.
Considering the dark, impenetrable vastness of the Earth’s oceans, the sea is clearly an exciting frontier for new species discoveries, and here too we find examples of many enigmatic species known from only a single specimen. One of the most impressive is a new species of stingray called the New Ireland stingaree (Urolophus armatus), which is known from a single solitary juvenile specimen caught during an expedition in 1822 led by René Primevère Lesson and Prosper Garnot in the seas of the Bismarck Archipelago of New Ireland, in Papua New Guinea. The specimen was subsequently taken to a museum in Paris, where it was stored away until finally being officially described as a new species in 1841, with some researchers arguing that it could possibly even be a new genus. This one lone specimen remains the only example of the New Ireland stingaree, and no further individuals have ever been caught or even seen. The New Ireland stingaree is rather unusual among others in its family in that it displays rows of denticles and spinules, or tiny sharp dermal thorns, along its back and the base of its tail as a defense mechanism against predators. Indeed, this feature is reflected in the stingaree’s latin name, with “armatus” meaning “armed.” Almost nothing is known about the New Ireland stingaree, as there was no record of the exact conditions under which it had been caught, and it is not even known just what its natural range, depth and habitat might be, or if it is extinct or not. Although museums and scientists have requested that any further individuals that are caught be donated for analysis, none have been forthcoming, and indeed the area where the original specimen was caught is one of the least surveyed areas of ocean on earth.
Equally enigmatic is the slender worm-eel (Leptenchelys vermiformis), an unusual looking, light yellow, worm-like fish which is known from one 12cm-long specimen dredged up from a mud bottom in 20 meters of water near Costa Rica. There is virtually nothing known about this species, and no new specimens have been caught. Another odd looking fish based on one specimen is the Walker’s toadfish (Batrachoides walker), which was discovered in 1953, when a single individual measuring 21 cm long was caught in the Gulf of Panama. The area where Walker’s toadfish was caught has been extensively scoured for further examples, yet none have been caught and it is feared to be extinct. There are larger species of fish known from a sole individual as well. The Somali grouper (Epinephelus indistinctus), which measures around 80 cm long (nearly 3 feet) long, was described from a lone specimen collected in 1991 off the Puntland coast of Somalia at a depth of 70 to 200 meters. Even though there has only been one specimen ever examined, fishermen of the area claim that the species is often caught by trawl and hand lines, although it is not specifically targeted. The Somali grouper is not considered to be extinct, and may even be common for all we know, but the difficulty in sending expeditions to the war torn, pirate plagued area have held back any further assessment and study of the unique species.
These are all surely reclusive creatures that have managed to exist on the periphery of the world we think we have mapped and fully understood. Here we have looked at the species that have eluded our understanding and have managed to reamain shadows, and there are many more like them. It seems that there is the possibility of unknown species roaming the wilds of our worlkd and the cold depths of our seas, and such cases only further fuel the speculation as to what might still be out there for us to find.