SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8843aff8e91cb659c3288d696175552dc033835476870488fc3d0ffa641e8ade' 
  AND token = 'mc7DxNs2OhBDzqK67neVYsXxnEyWh2vFChLyHWhODVI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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