SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2bf573067a41eee0ae5208b1b9f88aea64a83ad8b28d599be81c3d8b078eb128' 
  AND token = 'K/D+pfUkrGEtJD5+gTCK+ZwFfr60wczvU+ekxNTPfTg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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