SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e9eec217a5261ae35b69a4697315be689b98956248560e0edd7099a614dd2343' 
  AND token = 'FJ1zIxF1xVFXwIUkGEOibKRb2a+PJrF2ir5FbpwIzKU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}