SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aab1ac954df90dc3d3d2700a7ce3ce088a9a37e34efc2d634c1ba41946d67b7b' 
  AND token = 'qJ4b9EOYBhVVsiq1ZLQmGrY+XZP/oB0VuZEMaxhUk9g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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