SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '06f067d15e6f03d91d74b912d60a943cd1de5f3b2dfde5e2827a43836242f2d2' 
  AND token = 'Ijh1KuT7OWiBPkOvLIQAUKtpkRDSNm/tZzLlTVgOK/s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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