Classification

Domain: Eukarya
Kingdom: Protista
Phylum: Apicomplexa
Class: Sporozoa
Order: Eucoccidiida
Family: Cryptosporidiidae
Genus: Cryptosporidium
Species: Cryptosporidium parvum

Domain:
Cryptosporidium parvum is a parasite that belongs to the Eukarya domain as it has a nucleus, and membrane bound organelles.  It can infect both humans and animals and cause a disease commonly known as Cryptosporidiosis.

Kingdom:
Being that C. parvum have animal-like nutrition and phagocytes to ingest its food, it belongs to the kingdom Protista.

Phylum:

The phylum Apicomplexa is home to parasites which form small and infectious spores.  This phylum also contains many other parasites such as Plasmosdium vivax which can cause malaria for instance.  In figure 1, you can see some taxonomy of this phylum and how C. parvum relates in this tree to eight other malaria parasites.
By PMC from the National Library of Medicine
Figure 1

Class:
C. parvum produces both sexually and asexually. It is a parasitic protozoan and therefore belongs to the class sporozoa.  The sporozoa class contain rarely motile organisms that have reproducing spores.  Many other organisms that cause malaria also belong to this class.

Order:
The order Eucoccidiida is associated with mammals being the host of parasites, and C. parvum is just that. 
Within this order, life cycles that are both sexual and asexual are found.
  Telomerase Database
Figure 2
                      Figure 2 is the second phylogenetic tree.  In this particular tree, it is relating C. parvum to many other Eukaryotic organisms such as Homo sapiens and Saccharomyces cerecisiae; which is a type of yeast. 

Family:
The family Cryptosporidiidae is associated with the disease Cryptosporidiosis. Being that C. parvum is known to cause this disease, it belongs to this family.

Cryptosporidium actually means “mystery spore” in English. 

     Genus:  
The genus Cryptosporidium is specifically related to C. parvum as the life cycle is both sexual and asexual with the produciton of oocytes. These oocytes develop into different stages inside the host, particularly in the intestines, which will lead to infection.

                       

                                                                                                                                                                        

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