Deroceras panormitanum


           . (Photo: © Dr. Roy Anderson, MolluscIreland)

. (Photo: © Dr. Roy Anderson, MolluscIreland)


            Deroceras panormitanum . (Photo: © Dr. Roy Anderson,   MolluscIreland)

Deroceras panormitanum. (Photo: © Dr. Roy Anderson, MolluscIreland)


            Deroceras panormitanum : mantle lighter in color over the lung.   (Photo: © Dr. Roy Anderson, MolluscIreland)

Deroceras panormitanum: mantle lighter in color over the lung. (Photo: © Dr. Roy Anderson, MolluscIreland)


            Deroceras panormitanum:  genitalia. (Photo: © J. White-McLean,   U.F.)

Deroceras panormitanum: genitalia. (Photo: © J. White-McLean, U.F.)


Family

Agriolimacidae

Species

Deroceras panormitanum (Lessona & Pollonera, 1891)

Common name

Longneck fieldslug, Brown field slug

Description

Deroceras panormitanum is a chocolate-brown, grey-brown or almost black slugSlug:
A snail that either does not possess a shell or has one that is very reduced (no definite coiling) or internal.
that ranges in length form 25-30 mm. The body of the slugSlug:
A snail that either does not possess a shell or has one that is very reduced (no definite coiling) or internal.
is covered with dark brown speckles or flecks. The skin is very thin and almost completely translucentTranslucent:
Allows light to pass through but prevents the ability to see distinct objects.
. The mantleMantle:
A fleshy, membranous covering of the anterior portion of the body of a mollusc. It secretes the materials that form the shell.
is lighter in color over the lung and the sole is light grey. The mucus this slugSlug:
A snail that either does not possess a shell or has one that is very reduced (no definite coiling) or internal.
produces is thin, colorless and not excessively gummy. It may be possible to distinguish this species from D. laeve by the slope of the tail. The tail of this species gradually tapers to a point, while the tail of D. laeve is bluntly rounded. In order to confirm the identity of this specimen, dissection and observation of the genitaliaGenitalia:
The reproductive structures of an animal. May refer to either male or female structure.
are required.

Deroceras agreste. The penis (p) of this species is broad with only a single appendix.

Deroceras caucasicum: The penis is broad and has two appendixes at the tip with the vas deferens emerges between them. The posteriorPosterior:
Directional term: the rear or tail end of an animal.
edge of the penis is pigmented (dark-colored) and there is a hard "clam-shaped" shell-like plate inside the penis.

Deroceras laeve: The penis of this species is long, narrow and mostly twisted, with only a single appendix. It should be noted that a penis may be absent in some specimens.

Deroceras panormitanum: The penis in the species is broad and markedly bilobed with 4-6 appendixes.

Deroceras reticulatum: The penis (p) in the species is broad with only a single, irregularly branched appendix.

Native range

Southwest Europe

Distribution

North America:

  • U.S.: Western (Utah, Colorado, California)
  • Canada

South America: Columbia

Atlantic Islands: Canary Islands, Tristan da Cunha

Australasia: Australia; New Zealand

Africa: South including Marion Island

Europe

Ecology

The longneck fieldslug is a fast moving slugSlug:
A snail that either does not possess a shell or has one that is very reduced (no definite coiling) or internal.
, which is usually associated with human dwellings. It can be found in greenhouses, gardens, pastures, nurseries and commercial cropping systems. The diet includes living and dead plant material and this species has been reported as a pest of lettuce, asparagus, cereal and root crops. Deroceras panormitanum has been reported to display aggressive behavior involving tail lashing and biting and cannibalism. Eggs range from 1.5-1.75 mm in diameter and this species reproduce year-round.

Synonyms

  • Agriolimax panormitanum Lesson & Pollonera, 1882. Monografia dei Limacidi Italiani, Mem. R. Accad. Torino (2)35: 52. Type locality Sicily.
  • Limax panormitanum Lessona & Pollonera, 1882
  • Limax queenslandicus Hedley, 1888. Proc. R. Soc. Qld. 5(4): 150.
  • Agriolimax pollonerae Simroth, 1889. Nachr. Deutsch. Malak. Ges. 21(11/12): 179-82.
  • Agriolimax caruanae Pollonera, 1891. Boll. Mus. Zool. Anat. Comp. R. Univ. Torino 6(99): 3.
  • Agriolimax cecconii Pollonera, 1896. Boll. Mus. Zool. Anat. Comp. R. Univ. Torino 11(264): 6.
  • Agriolimax ceccomii var. ilvatica Pollonera, 1905. Boll. Mus. Zool. Anat. Comp. R. Univ. Torino 11(517): 3.
  • Agriolimax dubius Hoffmann, 1941. Zool. Anzeiger 136: 254-7.
  • Deroceras meridionale Reygrobellet, 1963. Bull. Soc. Zool. Fr. 88: 399.
  • Deroceras caruanae (Pollonera, 1991).

References

Anderson 2005; Barker 1879; Forsyth 2004; Horsak et al. 2004; Hutchinson and Heike 2007; Kerney et al. 1979 ; Reise et al. 2006; Wiktor 2000