SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8bb3db20acbcc095f9ee4de992640c1bc65644ab5d179a10a12b0fdca81c0506' 
  AND token = 'LiS5uW9yeHcRsL/Dgosxj6awIE4M0jNrEw2chzI5rAY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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