Gastropods

Slugs

Slugs and snails are the biggest pests in our garden. So much so they rank having their own tag in my blog.

Three-band Garden Slug

Threeband Slug

(Ambigolimax valentiana) – These are much smaller slugs than the Arion and the Banana slugs, but they can still do considerable damage. They are 1-2″ in length.

Chocolate Arion Slug

(Arion rufus) – This is the most common slug we see in our garden. I thought they were a type of banana slug, but they’re in a separate family from banana slugs. This is also the most commonly killed animal in our yard, and I have no regrets. They destroy everything, especially when plants are young. I often go out in the evening or early morning when they’re out and can find and dispose several dozen of them.

Although most of them are in the orange to brown coloration, I’ve also found an olive green version of this slug. It got damaged while collecting it so the photos aren’t that great, but doing research into the Chocolate Arion I found that there are green variations, so it’s not another species. If I come across another one I’ll try to be more careful collecting it. I just hate touching these things because their slime is awful to try to wash off. So I usually try to get them to stick to a stick, and the last one was uncooperative and ended up with some wounds.

California Banana Slug

(Ariolimax californicus) – This is the more yellow version, what I would call the true banana slug.

Pacific Banana Slug

(Ariolimax columbianus) – Unfortunately, we see these a lot too. Until I started researching them, I figured the Arion and the banana slug were just different colorations of the same species. I usually didn’t pay to much attention to them other than to make sure my shoe landed on top of them. The banana slugs are the largest slugs we see, they can get to be over 6 inches long.

Although slugs are hermaphrodites, I think you would call that appendage a penis.

Snails

Amber Snails

Aquatic Snail

Baby aquatic snail

(Family: Succineidae) – We found these tiny snails in our pond, most likely they hitched a ride on the aquatic plants we bought. They are only about 1/4 inch long, and I only noticed them when I was scooping out some of the silt that had collected at the bottom of our pond. They’re very hard to identify to a species unless you check their DNA.

European Garden Snail

(Cornu aspersum) – This snail was introduced to California near our old home in San Jose, either by Antoine Delmas, or Louis Pellier during the gold rush era. (I’ve seen references to both being the first to import this snail for gourmet purposes.) Now, they’re everywhere and you can never get rid of them. I use a lot of Sluggo, and regularly hand pick them, but like the slugs, they just come right back.

Worms

Aquatic Worms

(Order: Lumbriculidae)
While watching tadpoles in our pond, I was surprised to see this earthworm at the bottom. Looking a lot like the regular earthworms we find burrowing in our dirt, this one is adapted to living in the detritus that has settled at the bottom of our pond. It had two rows of iridescent spots running the length of it’s body. I estimate that it was about 2-3″ long, although I never saw the full length of it. I haven’t been able to find out any details or photos for this type of worm. (spotted 6/17/2019)

Earthworms

(Class: Oligochaeta)
I’m not sure if I’m going to be able to identify our earthworms or not. I found a good guide online, but honestly, even with a good macro shot they’re rather featureless. I can’t even make sense of the current taxonomy as it seems to be in flux. So for now I’ll just show some examples.

After my first attempt at identifying worms, I realized several things. First, I need to make sure I wash and inspect them first. One of the worms I had cut in half while digging, a common problem. For some worms though, that’s not fatal, as they can regrow both ends.

Second, I need to photograph them with a ruler in the photo, as size is very important in identifying them.

Third, I need to keep them wet, as worms breath through their skin, and dry out very quickly.

Fortunately, earthworms are very easy to locate so it shouldn’t be too hard to find another batch to study.

Example 1

This is the largest earthworm we find and they can reach 6-7″ in length. This one was about 4″ long. In both photos the mouth is on the left, anus is on the right.

Earthworm

Example 2

This one is much smaller, maybe 1 to 1.5 inches.