SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9da07b89e93e7c20bfcecef1d79e4684b090ae2afd3572b69629af930351194c' 
  AND token = 'LK1YHbdpRUFFJPyNZGPfjCybteZbBO3FbatzJcJP56E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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