#install the required packages (comment if needed)
install.packages("jsonlite", repos="http://cran.r-project.org")
install.packages("httr")

#Use the libraries
library(jsonlite) #https://cran.r-project.org/web/packages/jsonlite/
library(httr)

#Fill in the AphiaID you need
AphiaID <- 127160

#Build the URL to get the data from
url <- sprintf("http://www.marinespecies.org/rest/AphiaClassificationByAphiaID/%d", AphiaID);

#Get the actual data from the URL
classificationTree <- fromJSON(url)

#Walk the classification tree
currentTreeItem = classificationTree
while (!is.null(currentTreeItem )) {
	print(sprintf("ID: %d, RANK: %s, ScientificName: %s",
		currentTreeItem$AphiaID,
		currentTreeItem$rank,
		currentTreeItem$scientificname
	));
	#You can access the variables individually
	#print(currentTreeItem$AphiaID);
	#print(currentTreeItem$scientificname);
	#print(currentTreeItem$rank);
	
	#Get next item in the tree
	currentTreeItem <- currentTreeItem$child;
}