SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd42cb13799f662453be34c282d9fd13542f93ef3fb01f313551df353b3976606' 
  AND token = '1W4zhsg3MnY1QJEvgPPkMzK1wZLhfzV7RMU3iwaLEa0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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