SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5f5a4820b1792c9b343ca1679924ba879f7b14149324f10148800d289ea974fa' 
  AND token = 'igi6YLmVUhIYtcRjdzB3VnyeHAohonH0Tc0w0gPX1J0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

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