SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e568fe75d4a46daee031952a6eade54ae88cda892dd245271f8ef60bbd7c3ef7' 
  AND token = 'hBQAQjs5WXzpcdxss0rHl+XF/Di1vjszCghuEZY1IaU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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