SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f6032b5bdf4c5f205c42c3be9681f94a7234e46cb31dbc8a7573155f60d8a0de' 
  AND token = 'nDJP8D9D/VIeNbQBhRV7OMdNHrh9Vtf+3j1HgeKTgUA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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