SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dfdff8f0d2c31d6c98d48e1d098dc957e8f1911fd210397006f7db92ed833a9c' 
  AND token = '/5c5PgVic9vAJy5GXKKlcguBxuemnSVW4BsYc8a8DtQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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