SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'add55e3fe8306de5bd1981b3fbffd3ab991da138af5ce306dd893d44f35c765e' 
  AND token = 'Ww17Ug0PIE3k9xaY57qsN8OEoP9RS7VYX9lfptPy468=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}