SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '12f1fd871f48fd59b20610de91dc05117d1254fdad1cfd2ee4b962182c507c61' 
  AND token = '3N9U4PHj4KgCQK56UXegatmqpgkWEU6dKAMmxlv2MwQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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