SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9911f51508e95b3e7c2bb3363103204fc96deb8b9b37b4dbe817f02006d6fbac' 
  AND token = 'yFhEVnrUyqJQZnq0Ku24liC9VvFQD8EvLvqCtl4162M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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