SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '774d31649cb76ad12179ef62674ae0cddcc18437c599f62531fa3f5db177f589' 
  AND token = '45q6tQuNbn2q6XSs5Pk6ZLkoqZL6ArzeMNW628k43cU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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