SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '34eb5b4dfab748dc06cae7b254dad3d2defcfa8694807b536e1b7bbe7d733542' 
  AND token = 'Jtju0wePss5pCcKYcOq+DFvMq0Bs315l6I0X2L/Y9jU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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