Troglobites: Creatures of the Cave
Troglobites are generally small creatures which are adapted to live in caves. These adaptations are so extreme that these creatures are unable to survive on the surface, and thus spend their entire life in caves. For example, due to the dark nature of caves eyes are not used; many Troglobites, therefore, have underdeveloped eyes which may even be covered with skin. Darkness also removes the need for camouflage colouring animals on the surface may have, as such many Troglobites are albino. As seen in the photo, the Titanophyllum spiriarum is a species of millipede which is a Troglobite. This species was discovered in 2011 in Greece, has no eyes, and has a very palely pigmented body. Other Troglobites include the White Cave Velvet Worm, the Alabama Cave Shrimp, and the Beauty Rat Snake.
Due to Troglobites sedentary lifestyle they do not need much food to survive and thus gain most food from scavenging. Examples of food sources for Troglobites include plant debris, bacteria and animal faeces (such as bat guano – the excrement of cave-dwelling bats). So far nearly 8000 species of Troglobites have been discovered; however, biologists believe this number is not nearly at its maximum due to the number of caves yet to be explored or even discovered at all.
It should be noted that bats are not Troglobites but are Trogloxenes instead (animals that use caves but only for a short period e.g. overnight or to hibernate in over winter).Trogloxenes include birds, snakes and insects. There are also Troglophiles which spend part/ all of their life in caves; however, these species differ as they are not adapted to permanently living in caves so still maintain vision and pigmentation.
The first examples of Troglobites were discovered in Slovenia in the 1600s when heavy rain flooded caves and flushed out flesh-coloured creatures that were up to 10cm long with flat heads. At the time, this caused much hysteria as locals believed these were underdeveloped baby dragons.
~SA Picture: http://bit.ly/1JDBKv2 by P Stoev, N Akkari and H Enghoff.Further Reading: http://bit.ly/1cQ5iZl - The paper on T.spiriarum’s discovery