SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2752c8e806137769e7dadfa87c2f609f53f0edf846a764c009d5898c5f6461fc' 
  AND token = 'yws+6IeeE82pAB/TUIitdmrfBUpTP4ywDKlmEvF7nZk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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