SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '67c9082ea2bccbf16689906654197b008f23780b459e45c3f544164e37a0174a' 
  AND token = 'YyO1VC03EJ12zQ7mvpecAGqmUwgZgIDFbZp/bkWd/sI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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