SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45428526c0215a43734234faf5eea3d4ed444eab6a804715eee7b6482bde10f6' 
  AND token = 'JIWNpiUVIvkzXmxTWYRoJ9RQIjPaWdQX5z/y3Zw2B+A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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