SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d878cf64c904b3ba82cdabfebb1c97e42bbb7c54592f90c39a50b0873e36c61' 
  AND token = 'N0Iea20vD6YLM1/A2LDloCon3hn0vmYAVbJonYTa0dU=' 
  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"
    }
  }
}