SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1e0f5d0162ae7aecb69b1fa57571ed70649a201acad16bef2ec5f153098470d7' 
  AND token = 'UFmvC12SflTZCS+uVgRCTTOzab7JRT0aEspAbpXRqcI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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