SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '49e53d08be8eaaa944a2234235ec16a9d29dceb5b14d64c617444a84bf6101ec' 
  AND token = 'M0yiWwSrpEIhjwbUTttBZ+ABS5GfyS+OEkQiC/AE8XU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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