SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '07a3a9f67abea68ed8fcf7fd09ed67faeccae285eea984ba43a42a68121c55c0' 
  AND token = 'uzRr/Lc6sFqHdFoBjpdApvOlNHoWHAhy49xmGktoWHc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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