SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0c3629a99c347a522137f130c390657f80f1894858435f277819719459fcc99c' 
  AND token = 'WMTHIp8ZJYfFnSBvw+efXi16kyt6VM88q/fHPQPFhsM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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