Vampyrellidae


The family Vampyrellidae is a subgroup of the order Vampyrellida within the supergroup Rhizaria. Based on molecular sequence data, the family currently comprises the genus Vampyrella, and maybe several other vampyrellid amoebae. The cells are naked and characterised by radiating, filose pseudopodia and an orange colouration of the main cell body.
In former times the family Vampyrellidae contained several genera and was identical with the order Vampyrellida, also known under the name "Aconchulinida". However, based on molecular sequence data the family Vampyrellidae was restricted to a subgroup containing only the genus Vampyrella, and a different family Leptophryidae was established for the genera Leptophrys, Platyreta and Theratromyxa.

Characteristics

When free-floating, the cell is spherical and around 30 μm across, with long radially directed filose pseudopods as well as distinctive shorter club-shaped ones, so that it resembles a heliozoan. Moving, the cell stretches out and takes a more typical amoeboid form, with an obvious distinction between the clear periphery and pseudopods and the greenish interior. In this form it finds its way into algae cells and feeds on their interiors. At least one genus, Theratromyxa, also feeds on soil nematodes. A few other vampyrellids are parasitic on fungi. As such, these vampyrellids can be an important control of parasitic rust fungus of wheat and other crops.
Vampyrellids characteristically have mitochondria with tubular cristae. Together with the nucleariids they include the majority of the naked filose amoebae.

Systematics and phylogeny

Genera and species

There are at least 19 credibly described species that are either proved or likely to belong to the family Vampyrellidae, all of them belonging to the genus Vampyrella.
  • Vampyrella. 19 species.
  • *Vampyrella agilis
  • *Vampyrella atheyae
  • *Vampyrella closterii
=Gobiella closterii
  • *Vampyrella euglenae
  • *Vampyrella flabellata
  • *Vampyrella gomphonematis
  • *Vampyrella helioproteus
  • *Vampyrella incolor
  • *Vampyrella inermis
  • *Vampyrella lateritia
= Amoeba lateritia
= Vampyrella spirogyrae
  • *Vampyrella mirabilis
  • *Vampyrella multiformis
  • *Vampyrella pallida
= Vampyrina pallida
  • *Vampyrella peritrichophaga
  • *Vampyrella polyblasta
  • *Vampyrella radiosa
  • *Vampyrella soror
  • *Vampyrella ulothricis
  • *''Vampyrella variabilis''

    Phylogenetic tree

The following cladogram depicts the relationships between Vampyrellidae and other vampyrellid families. Of the 19 species, only 2 species of Vampyrella have been genetically sequenced, which limits the information on the internal relationships of the genus.