SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4569fc4e541b33587d542b8e77cfbfcca4fa28b89d0032db98d826234c951ef3' 
  AND token = 'GlgZz72HwHTN9GJddbVq3cWEhhBhIREeGgbRvtMAIvY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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