Neogregarinorida

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Neogregarinorida
Scientific classification
Domain: Eukaryota
Kingdom: Chromalveolata
Superphylum: Alveolata
Phylum: Apicomplexa
Levine 1970
Class: Conoidasida
Levine 1988
Subclass: Gregarinasina
Dufour 1828
Order: Neogregarinorida
Grassé & Schrével 1953
Families

Caulleryellidae
Gigaductidae
Lipotrophidae
Ophryocystidae
Schizocystidae
Syncystidae

The Neogregarinorida are an order of parasitic protozoa in the phylum Apicomplexa.[1] Species in this order infect insects are usually found in the fat body, hemolymph, hypodermis, intestine or Malpighian tubules. The most common site of infection is the fat body: many species are pathogenic for their hosts.

The species in this order are predominantly intracellular parasites.

Taxonomy[edit]

Six families are in this order, with 13 genera. The type genus is Ophryocystis.

They appears to have evolved from the Eugregarinorida.[2] Merogony as part of the life cycle separates them from the Eugregarinorida and appears to have been derived as a secondary characteristic.

A phylogenetic analysis of the small subunit RNA suggests Ophryocystis may actually be a eugregarine rather than a neogregarine.[3]

General characteristics[edit]

  • Merogony, gamogony and sporogony are present in all species
  • They are septate with deutomerites, epimerites and protomerites
  • A conoidal complex is present through a major portion of their life cycles
  • A mucron is formed from eversion of the conoidal complex similar to the eugregarines
  • Merogony occurs by budding from the meront cell surface as in the coccidia
  • Gamonts join in head-to-head syzygy (the conoidal complexes face each other)

References[edit]