Madagascarchaea gracilicollis is a member of the family Archaeidae, assassin spiders. It is merely 2 mm long and catches other spiders with venomous fangs at the end of its hugely elongated jaws (chelicerae).
These animals normally run upside down.
Etymology From Latin gracilis "slender" and collum "neck".
Distribution This species is endemic to Madagascar.
References
External links Picture of E. gracilicollis Article with a picture