SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '77c97ba0bd28d7a43b4e4143fba241fed9f4645e885a26a20287d107855729ee' 
  AND token = 'hFyW3PlCmhnwKWIFqGb0Rm3F8rNqilDeIUdgYV9Czjo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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