[ref. ID; 1618]
Heliozoa-like; endoplasm vacuolated or granulated, with carotin granules; numerous vesicular nuclei and contractile vacuoles; multinucleate cysts, sometimes with stalk; 50-700 um in diameter. (ref. ID; 1618)
[ref. ID; 1923]
Endoplasm red or brown. Body spherical or elongated. (ref. ID; 1923)
See Hyalodiscus.
[ref. ID; 4670]
Vampyrella has a cell body which is often spherical. The taxonomy of the genus has been confused in the past, as early observers may have had mixed cultures and confused the life cycles of contaminant organisms with the amoeba being studied. Confusion exists concerning the taxonomy of V. lateritia (Fresenius) Leidy, 1879. According to Gobi in 1915, V. spirogyra Cienkowski, 1865 is identical to Amoeba lateritia Fresenius, 1856 and therefore should retain the species name. Leidy in 1879 described Vampyrella lateritia as an independent species, which, in the view of Hoogenrad in 1907 was identical to V. spirogyrae of Cienkowski. However, Gobi considered that V. lateritia of Leidy and of Hoogenrad was not a Vampyrella at all but Gobiella borealis of Cienkowski (quoted by Gromov, 1976). Gobi also questions that validity of other Vampyrella species. This gives an idea of the confused state of the taxonomy of the genus as a whole. The feeding of Vampyrella has been observed to be either by ingestion of smaller algae or by penetration of filamentous algae. V. lateritia feeds by penetration of filamentous algae by filopodia (Cienkowski 1865; Leidy 1879; West 1901; Cash 1904). Other species of Vampyrella reported as feeding by penetration are: V. closterii Poisson & Mangenot, V. incolor Bruyne, V. intermis Klein, V. multiformis Zopf, V. pedata Klein, V. pedula Cienkowski, V. ulothricus Scherffel, V. variabilis Klein, and V. velata Gobi. Species reported as feeding by ingestion are: V. vorax Cienkowski, V. flabellata Cash, V. gomphoneinatis Haeckel, V. polyblasta Sokokin, V. pallida Mobius, V. radiosa Penard, V. agilis Penard, V. atheyae Zyloff, and V. gromata Alen. If these feed by ingestion only, and not by penetration, they would appear not to belong to the genus Vampyrella but to one of the genera of Nucleariidae. Since penetration of food organisms has been observed to a large extent in Vampyrella it is not intended to include the genus in the new family Nucleariidae, but to retain a separate family Vampyrellidae for Aconchulinida feeding at least in part by penetration of algal cells. The filopodia of Vampyrella frequently start from a common basis, and may fork but do not anastomose (West 1903). The filopodia of V. lateritia may project from a small portion or from the entire surface of the body (Leidy 1879). It was not recorded however under what conditions the cells were being examined. The presence of what could have been external bacteria was noted by Leidy in 1879. He described them being like "suctorial rays, pin-like, projecting from any part or the whole of the cell surface at once". However he went on to say that they were successively projected and withdrawn very quickly, whilst the longer rays (filopodia) were sometimes seen to vibrate. These observations are similar to those of Nucleosphaerium, but the bacteria did not move on their own accord, and were readily detached under the cover slip. The filopodia did not vibrate, but were slowly extended and withdrawn. Hyaline spheres were observed to run over the filose pseudopodia of Vampyrella (Penard, 1889). Spheres of the same sort were observed in Nucleosphaerium. (ref. ID; 4670)