Who wrote this poem and where was it published?

"The ancient armadillo
is as simple as the rain,
He’s an armour plated pillow
with a microscopic brain,
He’s thoroughly disinterested
in what the world has wrought,
But spends his time in contemplative
Armadyllic thought"

Hello.

Jack Prelutsky wrote the poem.

It appeared in Prelutsky's book "Zoo Doings: Animal Poems." 

From a 1997 article in the News Tribune of Tacoma:
 'Prelutsky would... go in search of armadillos - and all the other
exotic creatures who lived in The Bronx Zoo.
Years later, he dedicated "Zoo Doings" to The Bronx Zoo, and included
a tribute to his little armored friend:
"The ancient armadillo
is as simple as the rain,
he's an armor-plated pillow
with a microscopic brain..."'
source:
"A POET'S WAY WITH WORDS / JACK PRELUTSKY WRITES IN FASHION THAT
CHILDREN FIND APPEALING
The News Tribune; Tacoma, Wa.; May 12, 1997; page SL.3
http://pqasb.pqarchiver.com/TRIBnet/abstract/14490045.html?did=14490045&FMT=ABS&FMTS=FT&PMID=33027&desc=A+POET%27S+WAY+WITH+WORDS+%2f+JACK+PRELUTSKY+WRITES+IN+FASHION+THAT+CHILDREN+FIND+APPEALING

Prelutsky's "Zoo Doings" is available from a number of online
bookstores:

Amazon.com
http://www.amazon.com/exec/obidos/tg/detail/-/0688017827/

Abebooks.com
http://dogbert.abebooks.com/servlet/BookDetailsPL?bi=53418940

Alibris:
http://www.alibris.com/search/search.cfm?qwork=7394696

Half.com
http://half.ebay.com/cat/buy/prod.cgi?cpid=249593&domain_id=1856&meta_id=1

search strategy:
"ancient armadillo" on a library newspaper database

I hope this helps.

Excellent work; precise and to the point with good references. 
Provided additional relevant info as well.  Thanks!

http://home.austarnet.com.au/stear/meaning_of_life_to_an_armadillo.htm
has some information

Eco_e:
Thank you for the tip.
-juggler