SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '91a59e4fbff99d7b702181c9ec124467585aa139a4c47ee128ac99382599340b' 
  AND token = 'R9iiFmznwWaJ6/vdFO8f00UQbrp8i6qvP6QnrGTQKzA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

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