SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b52efbbdcd986d871745d6dc5e94dbc12f8c656661a5117bf6d0758cca1984d7' 
  AND token = 'qXIKSCtUPfUo0NfLnJ6sVerMUiUp+r9OoNA/yIuPMqg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}