SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '40a9034decb291e1b1d321863053af53389d9853b749ff44cec8977fed6f7168' 
  AND token = 'fg+RdiIutLz6o4acsklSCsWEzNanqy2tSokB8It1+iU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables