SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6dca0dfb035d213ae8b950c87a8235407aa0a77fa741cc4b725c84ef0ae63daa' 
  AND token = 'PUEZ0jCCjyXlqf6wGdCQtEVTVENqRqLDUWrGU8svrak=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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