Macizai masu dafi sunada yawa daga matakin teku har zuwa mita 4000. Ana samun macizan Turai a cikin Arctic Circle, amma a cikin yankuna masu sanyi irin su Arctic, Antarctica da arewacin 51 ° N a Arewacin Amurka (Newfoundland, Nova Scotia) babu wasu nau'ikan dafi baya faruwa.
Babu macizai masu dafi a cikin Crete, Ireland da Iceland, yammacin Bahar Rum, Atlantic da Caribbean (ban da Martinique, Santa Lucia, Margarita, Trinidad da Aruba), New Caledonia, New Zealand, Hawaii da sauran sassan Tekun Pacific. A cikin Madagascar da Chile, akwai macizai masu saurin kai-kawo.
Mulga
Krayt
Sandy Efa
Macijin teku na Belcher
Ragowar abinci
Marar maciji
Taipan
Macijin ruwan kasa mai gabas
Blue malay krait
Black Mamba
Tiger maciji
Philippine maciji
Gyurza
Gabon viper
Yammacin kore mamba
Gabas Green Mamba
Rushewar Russell
Sauran macizai masu dafi
Macijin daji
Taipan na gabar teku
Dubois macijin teku
Raunin maciji
Afirka boomslang
Macijin murjani
Macijin Indiya
Kammalawa
Macizai masu dafi suna haifar da dafi a cikin gland dinsu, galibi suna saka dafin ta haƙoransu ta hanyar cizon abincinsu.
Ga macizai da yawa na duniya, dafin yana da sauƙi da haske, kuma ana magance cizon ta yadda ya kamata. Sauran nau'ikan suna haifar da matsalolin asibiti masu rikitarwa, wanda ke nufin cewa maganin guba ba shi da tasiri sosai.
Macizai "masu mutuƙar" da "guba" ra'ayoyi ne daban-daban, amma ana amfani da su ba tare da sani ba ta hanyar musayar ra'ayi. Wasu daga cikin macizai masu haɗari - masu haɗari - kusan ba sa auka wa mutane, amma mutane sun fi tsoron su. A gefe guda kuma, macizan da ke kashe mutane da yawa su ne mafi dafi.
