SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd656030552bb08782c9ad9d7370a2a4f57cfd5ba5094feaec660121f37e6edc9' 
  AND token = 'WtggTgQu+v1IddO0OhEkUW1JFkbDqcHwjeoKGhVZtyY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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