SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f44e77826b863cf5b027844efb6068d37d83dc1d7e8dbc9231400ddefda6847c' 
  AND token = 'phS7T8wsq+GMLDXlbTNgCvQR0az8fyoQaFq2e69UNDQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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