Genus Naegleria Alexieff, 1912

Naegleria sp. cyst, showing pores (p) and nucleus delineated by perinuclear granules

Naegleria sp. flagellate stage, showing anterior flagella (f). Scale = 10 μm.

Museums

Regional Maps

• Naegleria Alexieff, A. 1912. Sur les charactères cytologiques et la systematique des amibes du group limax (Naegleria nov. gen. et Hartmannia nov. gen.) et des amibes parasites des Vertèbres (Proctamoeba nov. gen.). Bulletin de la Société Zoologique de France 37: 55 [emend. Calkins, 1913].

Introduction

Genus of more than 40 species, among which phenotypic differences are largely eco-physiological, including differential responses to temperature (expressed for individual spp as the ‘upper temperature limit’, Tu). Trophic form amoeboid with rounded, eruptive anterior lobopodium. Amoebae without beak-like rostrum or cytostome. Cysts always with one to several excystment pores closed by a plug and an interior ‘basal plate’, and usually with a single layer. Most spp differentiate to a non-trophic, rapidly swimming flagellate form, usually with two flagella. Flagellates are non-dividing in all but two named species, which have initially four flagella and divide once to form more typical biflagellate cells.

Distribution

IBRA and IMCRA regions

IBRA

Avon Wheatbelt (AW), Brigalow Belt North (BBN), Central Mackay Coast (CMC), Cape York Peninsula (CYP), Einasleigh Uplands (EIU), Esperance Plains (ESP), Eyre Yorke Block (EYB), Flinders Lofty Block (FLB), Gawler (GAW), Jarrah Forest (JF), Kanmantoo (KAN), Mallee (MAL), South Eastern Queensland (SEQ), Swan Coastal Plain (SWA), Warren (WAR), Wet Tropics (WT)

Diagnosis

Small amoebae moving by eruptive protrusions from a hemispherical anterior lobopodium. Differentiation to non-trophic flagellate cells in most species, usually biflagellate and unable to divide; two species produce tetraflagellate cells that divide once to smaller biflagellate cells; a few species have not been observed to differentiate. Cysts spherical to irregular in shape, with several excystment pores closed by a mucoid plug and an interior basal plate.

History of changes