The Victorian naturalist . unger birds. Jean Galbraith, Tyers 188 Vicf. Nat. Vol. 93 Victorian Non-Marine Molluscs, No. 16 BY Brian J. Smith* Many of the molluscs introduced in-to Australia are pest species, the mostwidely known being the CommonGarden Snail Helix aspersa. Howeverthe most widespread and devastating intheir effect on gardens, crops and pas-ture, are three small to medium slugsbelonging to the family are Deroceras caruanae, Dero-ceras reticulatum and Lehmannia(Lehmannia) nyctelia. The genus Deroceras is typified bythe body being spotted or without pat-tern but wit
The Victorian naturalist . unger birds. Jean Galbraith, Tyers 188 Vicf. Nat. Vol. 93 Victorian Non-Marine Molluscs, No. 16 BY Brian J. Smith* Many of the molluscs introduced in-to Australia are pest species, the mostwidely known being the CommonGarden Snail Helix aspersa. Howeverthe most widespread and devastating intheir effect on gardens, crops and pas-ture, are three small to medium slugsbelonging to the family are Deroceras caruanae, Dero-ceras reticulatum and Lehmannia(Lehmannia) nyctelia. The genus Deroceras is typified bythe body being spotted or without pat-tern but with no bands. The twospecies are both very common pastureand garden pests. Deroceras reticulatum (MuUer,1774) Fig. 1. This is a medium-sizedslug up to 50 mm in length, the bodybeing typically a pale buff colour withdark brown to grey reticulations,sometimes so dense as to give a darkbrown to grey appearance, sometimeswith white calcareous-looking spotsand reticulations. The body often ap-pears swollen and flaccid, the animal. Fig. 1 Fig. 2 Fig. 3 September/October slow-moving and not very the animal is disturbed, a milkywhite secretion is exuded all over thebody. Deroceras caruanae (PoUonera,1891) Fig. 2. This is a smaller andmuch shmmer slug reaching about30-40 mm in length. It is typically hghtbrown to grey in colour with an almosttotal lack of pattern. The body iscylindrical in shape with the head pro-truding a long way forward of themantle. The slug is very active in be-haviour, displaying extremely rapidcrawhng, the body producing a non-viscous colourless mucus. It is a cryp-tic animal, being hard to see becauseof its size, colouration and its habit ofnesting in crevices and the root sy-stems of plants. The genus Lehmannia has bandsand spots on the body, and internallythe rectum bears a long caecum. Lehmannia (Lehmannia) nyctelia(Bourguigrat, 1861) Fig. 3. This is amedium to large slug 50-60 mm inlength characterized by longitudinalblack bands on the body and man
Size: 1562px × 1599px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdec, booksubjectnaturalhistory, bookyear1884
