Worm Slug

The Worm Slug (Boettgerilla pallens) is a clear and pattern-less slug. Similar in appearance to the Ghost Slug(Selenochlamys ysbryda), it is one of only two species in the Boettgerilla genus, the other being Boettgerilla compressa.



Throughout most of the UK, the worm slug prefers forests, gardens and greenhouses, grasslands and woodlands where it can be found in damp habitats such as under logs, bark, stones and detritus. Outside of the UK the worm slug can be found in Europe, South America, North America and Canada. It is interesting to note that a specimen was found deep inside the Warton Quarry Mine in Lancashire in 2000. Slugs in mines are not uncommon, but it was the depth into the mine in which it was found that was unusual.



The worm slug is a slender pale slug that reaches 60mm in length. Colour varies from a pale creamy-white to grey or brown with visible yellow internal organs. The keel is sharp and the sole is pale yellow. Adults appear darker on their tentacles , mantle and posterior (tail end). The juveniles are noticeably paler as can be seen in these photographs.


Worm Slug - juvenile


The worm slug feeds on detritus, fungi, roots, carrion and the eggs of other terrestrial slugs such as the Arion genus. Laying several clutches of up to 6 eggs a time, the adult generally dies off afterwards.



The genus Boettgerilla was named after the famous naturalist Caesar Rudolf Boettger, as was the door snail genus Boettgeria. Other synonyms for this species include Boettgerilla vermiformis. The worm slug was first noted in England around the 1970s, although it may have been previously overlooked.