Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Will the real Limax nyctelius please step forward: Lehmannia, Ambigolimax, or Malacolimax? No, Letourneuxia!

Abstract

In 1861 Bourguignat described Limax nyctelius, a species of terrestrial slug from Algeria. Although the surviving identifiable syntype specimen is Ambigolimax melitensis, the description and illustration unambiguously refer to the arionid Letourneuxia numidica, because of the position of the pneumostome. We designate the lectotype as the specimen that Bourguignat illustrated (now lost), requiring L. numidica to be known as Letourneuxia nyctelia. Unfortunately, the name nyctelia has meanwhile been used for 4 other species, occurring across 4 continents. Simroth and Pollonera referred to a North African species lacking a rectal caecum, so potentially a Malacolimax. Quick and others referred to a species of Ambigolimax presumed native in North Africa but known also from Scottish greenhouses, Elba, South Africa, Australia, and New Zealand; we name it A. waterstoni n. sp. Its long penis and lack of a penial appendage caused confusion with a Lehmannia s.s. species with a similar penis form from the Carpathian Mountains, extending also from Albania across Bulgaria. The structures inside the penis are very distinct from those of A. waterstoni. We name it L. carpatica n. sp. Lastly, the species invasive in Great Britain and California, and reported also from France, Greece, and Spain, including the Canary Islands, is named here Ambigolimax parvipenis n. sp. It also has no penial appendage, but the penis is very short. The length of the rectal caecum emerged as a useful identification character: usually it extends to, or beyond, the posterior tip of the visceral sac in Lehmannia s.s., whereas in Ambigolimax it stops well short, except that it often reaches almost to the tip in A. valentianus.