Shedding Light on Vampires: The Phylogeny of Vampyrellid Amoebae Revisited

Abstract

With the advent of molecular phylogenetic techniques the polyphyly of naked filose amoebae has been proven. They are interspersed in several supergroups of eukaryotes and most of them already found their place within the tree of life. Although the ‘vampire amoebae’ have attracted interest since the middle of the 19th century, the phylogenetic position and even the monophyly of this traditional group are still uncertain. In this study clonal co-cultures of eight algivorous vampyrellid amoebae and the respective food algae were established. Culture material was characterized morphologically and a molecular phylogeny was inferred using SSU rDNA sequence comparisons. We found that the limnetic, algivorous vampyrellid amoebae investigated in this study belong to a major clade within the Endomyxa Cavalier-Smith, 2002 (Cercozoa), grouping together with a few soil-dwelling taxa. They split into two robust clades, one containing species of the genus Vampyrella Cienkowski, 1865, the other containing the genus Leptophrys Hertwig & Lesser, 1874, together with terrestrial members. Supported by morphological data these clades are designated as the two families Vampyrellidae Zopf, 1885, and Leptophryidae fam. nov. Furthermore the order Vampyrellida West, 1901 was revised and now corresponds to the major vampyrellid clade within the Endomyxa, comprising the Vampyrellidae and Leptophryidae as well as several environmental sequences. In the light of the presented phylogenetic analyses morphological and ecological aspects, the feeding strategy and nutritional specialization within the vampyrellid amoebae are discussed.

Tiny vampires in ancient seas: evidence for predation via perforation in fossils from the 780–740 million-year-old Chuar Group, Grand Canyon, USA

“…figure 4); the fact that a single microfossil may have multiple similarly-sized holes, consistent with the fact that a single predatory protist may make numerous holes in its prey ( [26,36]); and apparent specificity in hole size and microfossil species (figure 3), consistent with speciesspecificity in hole size and prey preference observed in vampyrellids [30,34].…”

“…In support of this view, the holes are similar to those made by modern predatory protists that perforate the resistant walls of their prey to consume the cell contents inside. This 'vampire-like' behaviour is widespread among eukaryotes, occurring in, for example, the amoeboid trophic phases of some amoebozoan slime moulds [24]; several close relatives of the Fungi [25,26]; the foraminiferan Floresina amphiphaga [27]; and several different cercozoan clades [28][29][30][31]. (Note that the term parasite has been applied to some of these organisms because they insert themselves fully inside the wall of the 'host' cell, consuming it from within [26].…”

Vampires in the oceans: predatory cercozoan amoebae in marine habitats

“…Three large, branched, naked soil amoebae, one tentatively identified as Arachnula impatiens, and the others attributed to a new genus Platyreta, were shown to be closely related and part of a diverse lineage known up to then only from environmental sequences ('Novel Clade 8' in Bass and CavalierSmith, 2004). More recently, Hess et al (2012) isolated and sequenced three more species: Vampyrella lateritia, V. pendula and Leptophrys vorax. The clade containing all of these sequenced vampyrellids branches as sister to the phytomyxid plant and stramenopile parasites/symbionts within the Endomyxa part of phylum Cercozoa (Cavalier-Smith, 1998;2002).…”

“…The genus Vampyrelloides (Schepotieff, 1912), comprising large branched amoebae of up to 1000 mm, has been proposed to be the only described marine vampyrellid (for example, Patterson, 1999;Patterson et al, 2000), but was not included in the ultrastructural study by Rö pstorf et al (1994). Therefore, all genera currently accepted as vampyrellids based on life cycle, feeding behaviour, ultrastructural data (Rö pstorf et al, 1994), and molecular phylogenetic analyses (Bass et al, 2009;Hess et al, 2012) seem to inhabit non-marine environments only. In the absence of microscopy evidence to the contrary and concordant with the available sequences in GenBank, Hess et al (2012) suggested that vampyrellids may thus be largely confined to non-marine habitats.…”

“…Therefore, all genera currently accepted as vampyrellids based on life cycle, feeding behaviour, ultrastructural data (Rö pstorf et al, 1994), and molecular phylogenetic analyses (Bass et al, 2009;Hess et al, 2012) seem to inhabit non-marine environments only. In the absence of microscopy evidence to the contrary and concordant with the available sequences in GenBank, Hess et al (2012) suggested that vampyrellids may thus be largely confined to non-marine habitats. By contrast, we now used a combined approach of culturing and sequence database mining and present new results suggesting a marine origin for the whole vampyrellid clade, and revealing that the diversity and abundance of vampire amoebae in marine habitats is huge.…”