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ARKive’s Top 10 EDGE species

By on September 7, 2011 in EDGE Updates, Uncategorized

Do you know your solenodon from your numbat? Here at ARKive we have a soft spot for the weird and wonderful and want to put a face to the names behind some of the world’s most bizarre and threatened species.

ARKive is an initiative of Wildscreen, a not-for-profit organisation whose mission is to inspire the global community to value and protect the beauty and wonder of the natural world. With over 13,000 fascinating species fact-files and over 80,000 films and photos from the world’s best wildlife photographers and filmmakers, gathered together and freely available online at, we hope to shine a spotlight on the world’s biodiversity. Like the EDGE programme we also want to raise greater awareness of those rare and unusual species that represent a unique and irreplaceable part of the natural world and truly are one of a kind.

So to celebrate our love of all things peculiar, we have had a dig around the ARKive collection and put together a list of our Top Ten EDGE species.


10. Chinese giant salamander

Growing to a staggering 1.8 metres in length, the fully aquatic Chinese giant salamander is the largest salamander in the world and one of the largest living species of amphibian. It is one of only 3 living species in its taxonomic family, whose ancestors diverged from all other amphibians over 170 million years ago during the Jurassic Period.
ARKive photo - Chinese giant salamander on leaves


9. Numbat

Termites watch out, the numbat’s about! The only marsupial to feed exclusively on social insects, the numbat uses its long, thin tongue to eat around 20,000 termites per day, equivalent to ten percent of its own body weight! Unlike most marsupials the numbat is active during the day, reflecting the behaviour patterns of termites, spending most of its active hours searching for food. The numbat is the only member of its taxonomic family, meaning that it is genetically, as well as behaviourally, unique.

ARKive photo - Numbat, head detail


8. Mallorcan midwife toad

Thought to have become extinct for over 2,000 years until it was discovered in 1977, the Mallorcan midwife toad is a true “living fossil”, but sadly only 500 to 1,500 adult pairs are thought to be left in the wild.

This species also has a very unusual life cycle. Female Mallorcan midwife toads compete to be selected by males and if successful, the female then wraps a string of eggs around the male’s legs.      The male cares for the developing eggs until they hatch, leaving the female free to mate again.       With its bizarre life cycle and its scarcity, the Mallorcan midwife toad definitely deserves to be in our Top 10.

ARKive photo - Mallorcan midwife toad, close up


7. Pygmy three-toed sloth

Found only on a tiny island off the coast of Panama, the pygmy three-toed sloth is a mini version of its larger mainland relatives. Unusually, sloths have forearms that are much longer than their thighs, so they crawl on their elbows rather than their hands when they’re on the ground. Luckily for the pygmy three-toed sloth, this bizarre adaptation helps it to climb safely and securely in trees. The pygmy three-toed sloth definitely fits the EDGE criteria as not only is it unique in appearance even amongst the sloths, it is Critically Endangered.

ARKive photo - Close up of pygmy three-toed sloth


6. Elkhorn coral

The Critically Endangered elkhorn coral is amongst the fastest growing coral on reefs. As the name suggests, these large corals form structures that look like elk horns branching across the bottom of the sea floor. Even though there are several species of Acropora corals, the elkhorn coral is one of only two species in the Caribbean, meaning that this beautiful coral is pretty special!
ARKive species - Elkhorn coral (Acropora palmata)


5. Amazonian manatee

First described as a curious combination of a hippopotamus and a seal, the Amazonian manatee is a bizarre-looking aquatic mammal. The sirenians (manatees and dugongs) are actually more closely related to elephants than to marine mammals such as whales and dolphins and are unique in that they are the only plant-eating marine mammals. Recent evidence also suggests that manatees may possess a unique 6th sense that enables them to detect pressure changes through sensory hairs!

ARKive photo - Amazonian manatee


4. Elegance coral

The elegance coral makes it onto our Top 10 list mainly because it is incredibly pretty! However, this corals beauty is also its downfall, as it is particularly prized in the aquarium trade. Like other coral species, the elegance coral is threatened by over-fishing, pollution, habitat damage and thermal stress.

ARKive photo - Catalaphyllia jardinei polyps extended


3. Varaldi’s spadefoot toad

A burrowing species, the Varaldi’s spadefoot toad actually remains dormant underground for half the year, spending the summer months underground. It is only active in the autumn and winter, when it comes to the surface during the night to feed. Though, they do not really hunt. They don’t really hunt for their prey; instead, they wait for invertebrates to come to them! ARKive media donor and EDGE Community memberPhilip de Pous is studying Varaldi’s spadefoot toad to determine its conservation status.

ARKive photo - Close up of Varaldi's spadefoot toad


2. Golden-rumped sengi

This golden-rumped elephant shrew or sengi is not closely related to shrews as its name would suggest but is in fact more closely related to an ancient group of African mammals that also includes elephantsDr Galen Rathbun from the IUCN SSC Afrotheria Specialist Group, has kindly contributed images of this species to ARKive and EDGE and is working to develop conservation strategies to protect this little known species.

ARKive photo - Golden-rumped elephant-shrew


1. Hispaniolan solenodon

Why does the Hispaniolan solenodon deserve to be our number one? Firstly it’s venomous, which, whilst also being pretty cool, is rare amongst mammals. Secondly, out of around 25 endemic land mammals that once inhabited Hispaniola, it is one of only two species that survive to this day, with the hutia being the other.

This ancient and distinctive species faces very real and immediate threats to its survival, but with the help of both national and international conservation organisations working to protect this species it is hoped that the solenodon will not suffer the same fate as Hispaniola’s other mammals. ARKive media donor Dr Jose Nunez-Mino is leading EDGE’s Last Survivors, a fantastic project working to save the Hispaniolan solenodon.

ARKive photo - Close up of a Hispaniolan solenodon

Explore to discover thousands more of the world’s weird and wonderful species.