SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '195944a514582f8e23e3caefe027af54fd0a3eee8339fc1296f0c435c96f1394' 
  AND token = 'd+RmfObiXX9LEacFnoGtkUEPD0lDr+w98dRXMEzlmns=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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