SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ffc32aacbf2ff0066b65e0b01ed9a108980c35d574fe6d67edff0cca8e017b91' 
  AND token = 'iA00DlgGVOpWbsjZ/SNbNpr1B/CBluRmLsabeVXdRe0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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