SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62f748d56f874765a8271acdb8fec4ed68ad8859cfc828e96c93cda0c0313622' 
  AND token = 'DGiAJUQpx+nKYB3E7AzPwPBlNhqeeSGliUzC7KsqPdQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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