SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3387a8cbe6e61bfceca73027d736148ad8f28bbc484047dde6325957d51fec84' 
  AND token = 'QGzB9uowPgTZo9rlrBXeQgXZjCGwA5VYlOGFGn6+6vw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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