also: りくにあがったカッパ
a fish out of water; a kappa on land
Idiomatic expression describing someone who is out of their element and unable to perform as usual. The literal image is of a kappa, a water creature, stranded on land.
See also: 河童
In my new workplace, I feel like a fish out of water.
河童 is the mythical water creature itself; 陸に上がった河童 is the full idiomatic expression meaning 'out of one's element'.
Standard kanji spelling for the idiomatic expression.
Variant with katakana カッパ and reading りく; less common but still used.
From the image of a kappa (a water imp) being helpless on dry land; the expression is a direct metaphor for being out of one's element.