SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eddf1ad8bc044e2597c4b5bd173903ee8f830697706a26845651f1c2c0506ff3' 
  AND token = 'sYFj8GTzb/JHhvk5cgHN6Z+G6qOkbXeG3WzjkO/CEVc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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