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Jet Slug

Milax gagates

Summary 2

Milax gagates, known by the common name greenhouse slug, is a species of air-breathing, keeled, land slug, a shell-less terrestrial gastropod mollusk in the family Milacidae.

Distribution 3

occurs (regularly, as a native taxon) in multiple nations

Morphology 4

External: Uniformly dark gray to black (Herbert 1997); mantle sometime with light spots (Abbes et al. 2010); weak grooves in skin (Abbes et al. 2010); dark keel; horseshoe-shaped groove in mantle; pneumostome without a pale edge, and a bit post-median on the mantle; clear, sticky mucus; pale three-part sole with chevron banding of the center section (Quick 1960).

Internal: Internal shell 4 x 2.5 mm, white, and saddle-shaped; epiphallus widest at its end and with a protuberance below the apex (unlike T. sowerbyi or T. budapestensis); penis narrows as it enters the atrium, with 2 dilations before it does so (papillae inside) (Quick 1960); penial stimulator usually smooth inside or sometimes with small papillae or spines (Wiktor 1996); oval spermatheca with short duct; conical stimulator in the atrium; thick spermatophore, 10 mm long and widest in the middle (Quick 1960).

N and S Mediterranean morphs: Northern morph has a smoother skin, lighter sole, and smooth genital stimulator; southern morph has more pretruding tubercles, darker sole, and two rows of papillae on genital stimulator (Quick 1960).

Eggs: 2 x 1.5 mm, transparent, thin (smaller than those of T. sowerbyi or T. budapestensis) (Quick 1960).

Size 5

35-50 mm long body, mantle 10-20 mm long (Abbes et al. 2010). To 60 mm long extended (Herbert 1997).

Look alikes 6

Resembles Milax nigricans and Milax gasulli externally, with features of genital stimulator diagnostic (Abbes et al. 2010).

Habitat 7

Habitat Type: Terrestrial

Number of occurrences 8

Note: For many non-migratory species, occurrences are roughly equivalent to populations.

Estimated Number of Occurrences: > 300

Comments: In California it occurs in 23 counties: Alameda, Butte, Contra Costa, Kern, Lake, Los Angeles (incl. Santa Catalina Island), Napa, Orange, Sacramento, San Bernardino, San Diego, San Francisco, Santa Barbara (incl. Santa Cruz Island), Santa Clara, Santa Cruz, Stanislaus, Tehama, Trinity, Ventura (incl. Anacapa Island), Monterey, San Luis Obispo, San Mateo, and Riverside (McDonnell et al., 2009). It was recently reported as introduced in Cachoeirinha, Rio Grande do Sul State, Brazil (Agudo-Padron, 2009).

Sources and Credits

  1. (c) Jaume Torán, some rights reserved (CC BY-NC-SA), https://www.flickr.com/photos/28747427@N08/2676826863/
  2. (c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Milax_gagates
  3. (c) NatureServe, some rights reserved (CC BY-NC), http://eol.org/data_objects/28873134
  4. (c) Paustian, Megan, some rights reserved (CC BY-NC), http://eol.org/data_objects/17764976
  5. (c) Paustian, Megan, some rights reserved (CC BY-NC), http://eol.org/data_objects/17764977
  6. (c) Paustian, Megan, some rights reserved (CC BY-NC), http://eol.org/data_objects/17764975
  7. (c) NatureServe, some rights reserved (CC BY-NC), http://eol.org/data_objects/28873136
  8. (c) NatureServe, some rights reserved (CC BY-NC), http://eol.org/data_objects/28873130

More Info

iNat Map

Establishment introduced
Slug or snail slug
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