I'll bet there's a misprint on the site and agree with you, wwh, that probably crustaceology was the word intended--but I'll go hunting through some sources to check out this cussed custacelology!

Here's something from MW on crustaceology with a synonym you might like:

"Carcinology \Car`ci*nol"o*gy\, n. [Gr. ? a crab + -logy.] (Zo["o]l.) The department of zo["o]logy which
treats of the Crustacea (lobsters, crabs, etc.); -- called also malacostracology and crustaceology.
Source: Webster's Revised Unabridged Dictionary, © 1996, 1998 MICRA, Inc."