SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8bd8490c3ee016d7e95507cb1eb5ba9d2dd36d49b224e7fe46d57c4d6f10ed7e' 
  AND token = '6HN6wP1yqLfGUdr/gsogiVxRlCVvz2PLCTxIbmBnWbE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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