SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '65fe69ba9825d7ccde1a8a450cd5bf18d41ceb07c1b44e1c4472fa1d48c9816f' 
  AND token = 'M5MK5HX3tFjjsYyZwsOWze6KNq2esVR/Jgpl7+G5r7Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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