SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '404d56d5c3a8ac56f705eb7df3e05dce6c9716664671c5e52be99a1b0aeeaa19' 
  AND token = 'wXQI4JjhCjL/gVlQuDxzJIfYzptnwWigqQcpzSe2SWU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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