Opener in practice rather too rough for cricket class? (10)

'cricket class?' is the definition.
The definition and answer can be both animals as well as being singular nouns.
Perhaps they are linked in a way I don't understand?

'opener in practice rather too rough' is the wordplay.
'opener in' suggests taking the first letters (the letter which opens the word).
'rough' indicates anagramming the letters (a rough or broken ordering of the letters).
The first letter of 'practice' is 'p'.
'p'+'rather'+'too'='prathertoo'
'prathertoo' with letters rearranged gives 'ORTHOPTERA'.

'for' acts as a link.

Can you help me to learn more?