What could be eating my Cucumber leaves?

[Nick Blair]

I noticed whole leaves go fast , on one of them all the leaves have been eaten.

Is it likely to be a Snail or some other pest? In the past I have seen Snail tracks even on a Cucumber leaf but no damage. So I thought they did not like Cucumber plant leaves. Could it be an insect of some sort?

[taff]

slugs



..

[Nick Blair]

The plant is very spikey, it is Marketmoore variety.