The Neogregarinorida are an

order Order, ORDER or Orders may refer to: * Categorization, the process in which ideas and objects are recognized, differentiated, and understood * Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of d ...

parasitic Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has c ...

alveolates in the

phylum In biology, a phylum (; plural: phyla) is a level of classification or taxonomic rank below kingdom and above class. Traditionally, in botany the term division has been used instead of phylum, although the International Code of Nomenclature f ...

Apicomplexa The Apicomplexa (also called Apicomplexia) are a large phylum of parasitic alveolates. Most of them possess a unique form of organelle that comprises a type of non-photosynthetic plastid called an apicoplast, and an apical complex structure. T ...

. Species in this order infect insects and are usually found in the

fat body 300px, Stained cells of an insect fat body Fat body is a highly dynamic insect tissue composed primarily of storage cells. It is distributed throughout the insect's internal body cavity; the haemocoel, in close proximity to the epidermis, dige ...

hemolymph Hemolymph, or haemolymph, is a fluid, analogous to the blood in vertebrates, that circulates in the interior of the arthropod (invertebrate) body, remaining in direct contact with the animal's tissues. It is composed of a fluid plasma in which ...

hypodermis The subcutaneous tissue (), also called the hypodermis, hypoderm (), subcutis, superficial fascia, is the lowermost layer of the integumentary system in vertebrates. The types of cells found in the layer are fibroblasts, adipose cells, and macro ...

intestine The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the digestive system that leads from the mouth to the anus. The GI tract contains all the major organs of the digestive system, in humans ...

Malpighian tubule The Malpighian tubule system is a type of excretory and osmoregulatory system found in some insects, myriapods, arachnids and tardigrades. The system consists of branching tubules extending from the alimentary canal that absorbs solutes, water, ...

s. 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

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

Ophryocystidae The Ophryocystidae are a family of parasites in the phylum Apicomplexa.Leger L (1907) Les schizogregarines des tracheates. L Le genre Ophryocystis. Arch. Prot. 8: 159-202 Species in this family infect insects ( Coleoptera and Lepidoptera). His ...

and

Schizocystidae The Schizocystidae are a family of parasitic alveolates in the phylum Apicomplexa. Species in this family infect insects (Diptera, Coleoptera and Hemiptera). History This family was created by Léger and Duboscq in 1908. Taxonomy Three genera a ...

) belong to the suborder

Schizogregarinina Schizogregarinina is a superfamily in the phylum Apicomplexia. History This superfamily was created by Léger in 1907.Léger L (1907) Les schizogregarines des tracheates. Le genre ''Ophryocystis''. Arch Prot 8: 159-202 Taxonomy There are two ...

. They appear to have evolved from the

Eugregarinorida The ''Eugregarinorida'' are the most large and diverse order of gregarines — parasitic protists belonging to the phylum Apicomplexa. Eugregarines are found in marine, freshwater and terrestrial habitats. These species possess large trophozoite ...

. 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.

General characteristics

Merogony Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments they are exposed to during their complex life cycle. Each stage in the life cycle of an apicomplexan organism i ...

gamogony Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments they are exposed to during their complex life cycle. Each stage in the life cycle of an apicomplexan organism i ...

and

sporogony Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments they are exposed to during their complex life cycle. Each stage in the life cycle of an apicomplexan organism is ...

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 Apicomplexans, a group of intracellular parasites, have life cycle stages that allow them to survive the wide variety of environments they are exposed to during their complex life cycle. Each stage in the life cycle of an apicomplexan organism is ...

cell surface as in the coccidia * Gamonts join in head-to-head syzygy (the conoidal complexes face each other)

References

Conoidasida Apicomplexa orders Parasites of insects {{Apicomplexa-stub