SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2b8baf8d98fdfa7ad37058821cb7f333623a8c36bd4b35b136835b4ce5160684' 
  AND token = 'PIuQkMktZ4xGyYPJN9azvslBK+1ekmaWO+l7tgO6ioY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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