SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6866defc8b3ec0f464dc7152b5fbd85f144e1f897a8a5233c3a9a25a2015962d' 
  AND token = 'Zit8KTZ61E0P9bJz6gM7YgTsU/il+diTAxpCU/WfuRw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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