SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd5c9e006f409aaca0118aa0a3828afe0f9c044e77902b19563201afbf854dc64' 
  AND token = '4d/yztGsxsSwnFlZLtKeq3ZYuT+BbtJUi5iX37qCkg4=' 
  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"
    }
  }
}