SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cac21b14fccfea59bad2a5eb83864da85c876dfa42dd325b60f30c1db50b4ca7' 
  AND token = 'wBNKSeOvnhVTPRZ+Noa5pCLSLTbL052e0CGKmY9IMrQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

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