Species ID needed

[pinkunicorn]

Found in Amsterdam. My best guess is that this guy is a Milacidae sluggy, as he is a keelback but does not look like a Limax or Lehmannia slug. The black stripe is a really prominent keel. The animal is about 2cm long in the picture retracted, 4-5cm stretched out. I have three babies as well, and they look the same except the keel is even sharper, giving the slug a funny shape like a raspberry boat candy when retracted! The head is quite small relative to the body and is coloured black. Quite small tentacles.

What do you think? I've never seen these guys before.

[pinkunicorn]

Uhm white/pale stripe, not black. Also, the big slug is the one needing ID. The two black babies are Arion hortensis, I believe.

[malacophile]

Are you sure it's not a Deroceras reticulatum?

[pinkunicorn]

I've not seen a live D.retic but I understand they look like D.invadens on the outside, and the only way to tell them apart is the mating. There's lots of D invadens here to compare to and these guys are quite different. The body is twice as wide in the larger individual (which I assumed to be a juvenile). Adult invadens are the size of the babies of this species on average. This guy's skin is also a lot less "watery" and transparent, much more like an Arionid's.

Do you have confirmed D.retics? How big do they get?

I started wondering about the actual lenght in the picture btw. I first thought it was 4cm retracted (I forgot what it was when taking the pic), then changed that to 2cm as I saw the slug in much smaller form in his box... but the little black ones measure just 1cm in the position they are in the pic. So it might be longer than 2cm in that position!

[pinkunicorn]

These are the candies, btw. I forgot it's a Scandinavian candy so not everyone might be familiar with the shape. The babies are just like this when retracted! Adult a bit less prominent in the keel but still more prominent than anything else I've seen.

[malacophile]

I don't have any concrete IDs on the retics, but the ones in my area fit all of the descriptors, right down to the sticky, milky slime.

The retics I have get around 5cm long and are also pretty big around. They also have that dorsal keel going on.

[graemepryce]

Don't know if this is the right place to mention this but I keep seeing slugs I can't identify on my front garden. I haven't got any pics yet and I don't keep slugs so I only see them occasionally but I'll describe and if anyone knows if they are common or what it would be interesting.

They are massive for British ones, a good 5 inches and brown. The eyestalks aren't that long and there is an obvious large breathing hole on the side. Strangest bit is they have a bright orange lip around the edge of the foot and really obvious lines along them in the skin. I've seen a few now so they obviously like something in my garden. I saw the tell tale giant slime stain on my step one day too so I think they are mating as well. I grow a lot of roses and herbs out there if that helps at all.

I doubt they are anything special but I don't recall seeing anything like them before and slug websites are even less informative and easy to find than snail ones!

[Kitana]

Arion ater very common England. (to the description of the slug above)

[pinkunicorn]

Sounds like A.ater yes. We got some here but mostly I see A.vulgaris (looks the same but doesn't have a different coloured "skirt", in vulgaris it's usually the same colour as the body). Be glad for your arions! A.vulgaris is taking over and other arions are disappearing as they're not as hardy. They are really nice slugs btw, personality wise. And you can train them to stay in certain parts of your garden by providing food (soaked fish/cat pellets, rotting and old veg and fruit, washed peels... anything goes, these guys aren't picky when they are hungry wild animals). Then watch hundreds of slugs swarm the food at around midnight. I've been training some for a week now and they arrive already at 8pm for dinner, lol.

[Kitana]

It looks like a Tandonia budapestensis, or something around there

[pinkunicorn]

I think that's what it is indeed! The burrowing behaviour Wikipedia mentions I've already noticed. I've quite a few of these guys now, maybe 10. They're really cute!

Thanks!

[Dumbledore]

You're right, that is super cute. But most snails and sluggies are.

[pinkunicorn]

Actually my slugs are Tandonia sowerbyi! I just checked the soles of the foot on them and it's pale. T.budapestensis is supposed to have a dark stripe there. Otherwise the species look identical.

[Dumbledore]

Wow, that's cool!