Myxococcus llanfair­pwll­gwyn­gyll­go­gery­chwyrn­drobwll­llan­tysilio­gogo­gochensis is a gram-negative, rod-shaped species of myxobacteria found in soil.

A draft sequence of its genome[2] showed significant differences from all previously known species of the genus Myxococcus.

The species was isolated from soil collected near the village of Llanfairpwllgwyngyll, on the island of Anglesey in North Wales, and its specific name was given after the settlement's 58-character lengthened name (Llanfair­pwll­gwyn­gyll­go­gery­chwyrn­drobwll­llan­tysilio­gogo­goch),[1] which is the longest in Europe.

[4][self-published source] The species name has been criticized for not following recommendations in the International Code of Nomenclature of Prokaryotes, that specifies that long and difficult to pronounce names should be avoided.

[5] Since the International Journal of Systematic and Evolutionary Microbiology plays an important role in nomenclature validation,[5] some critics have argued that the species name can not be considered valid before being published in that Journal.