Gregarina garnhami
Gregarina garnhami
Gregarina garnhami is a tiny, single‑celled organism in the group Apicomplexa. It is a parasite that lives in insects, especially the desert locust, and can infect a large portion of a locust population—sometimes up to 100%.
Classification and discovery
- It belongs to the domain Eukaryota, within the SAR group and Alveolata. It is in the phylum Apicomplexa, class Conoidasida, subclass Gregarinina, order Eugregarinorida, family Gregarinidae, genus Gregarina.
- The species name is garnhami, described by Canning in 1956.
- A notable feature is its autofluorescence, meaning it glows under certain light without any staining.
Relationship to similar species
- In 1996, some scientists argued that Gregarina garnhami was the same species as Gregarina acridiorum, a parasite of various locusts. In 2021, studies using both appearance and DNA showed they are distinct, confirming that G. garnhami is its own species. G. garnhami can look different in different geographic locations and hosts.
What it looks like and how it lives
- G. garnhami is a septate gregarine, which means its cell is divided into parts: epimerite (the attachment organ), protomerite, and deutomerite. The cell has a trilayered pellicle made of membranes that helps protect and shape it.
- The cell body is divided into two zones: an clear ectoplasm that contains microtubules, and a granular endoplasm rich in storage material (paraglycogen), giving a brown‑yellow color when seen under light.
Where it sits in the locust
- It lives on the surface inside the desert locust’s gut, mainly in the caeca and midgut. It attaches to the gut lining with the epimerite and feeds without piercing the host’s cell membrane.
Life cycle in simple steps
1) Oocysts are shed in locust feces and end up on plant material.
2) Other locusts eat the contaminated plants; the oocysts burst open in the gut.
3) Eight sporozoites are released and move through the gut lining.
4) They attach to gut epithelial cells and become trophozoites.
5) Trophozoites grow and form a paired stage (gamont) that fuses with another gamont (syzygy).
6) The fused cells become zygotes, which develop into new oocysts.
7) Each oocyst contains eight haploid sporozoites, ready to start the cycle again.
Impact on hosts and potential use
- G. garnhami generally lives in a way that is not highly harmful, but it can cause weight loss in some cases.
- Because it specifically infects certain locusts, it has been discussed as a possible tool for biocontrol of the desert locust (Schistocerca gregaria) in some regions.
Summary
Gregarina garnhami is a gut-dwelling, single-celled parasite of desert locusts, with a distinct life cycle and morphology. It is usually host-specific to Orthoptera insects, can be highly prevalent in some locust populations, and shows interesting features like autofluorescence and clear variations across different environments.
This page was last edited on 3 February 2026, at 00:05 (CET).