SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41823cf0c7fa2b5c0b95f21e09cb4d9217e44cc791d132c56147dd49e2ca0f3b' 
  AND token = 'cGBB5enmGl2Z0XUnBDIKmDj3XQVGQmTMGh6nJYiAG/g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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