Unonkala
thumb|right|280px|Unonkala uyasebenza eSea urchin

Oononkala bakwiphylum Crustacea. Baziidecapods (banemilenze elishumi), ehambisana nelobsters, iicrayfish kunye neshrimps. Oononkala zenza ulandelelwano kwiidecapods, olo landelelwano kuthiwa yiBrachyura. Umzimba wayo omfutshane wogqunywe ngeexoskeleton engqindilili. 

Oononkala baliqela elinempumelelo, bafumaneka kulo lonke ihlabathi.  Banokhuseleko oluluqilima ngenxa yeeshell-breakers. Uninzi loononkala luhlala emanini olwandle, kodwa kukho bakwako nabo bahlala emanzini ahlaziyekileyo, kanti abanye babo bahlala emhlabeni. Abona nonkala bancinane balingana nokhoza lwephizi; oyena nonkala mkhulu ngunonkala osisigcawu saseJapan ukhula abe nobude beemitha ezi-4. About 7,000 species are known.Walters, Martin & Johnson, Jinny. 2007. The World of Animals. Bath, Somerset: Parragon.


why do unonkala crabs have such strong protection
Answer: shell - breakers