arachnula arachnula arachnula is a genus of amoeboid eukaryotes first described by leon cienkowski in 1876. arachnula scientific classification domain: eukaryota clade: diaphoretickes clade: sar phylum: endomyxa order: vampyrellida family: vampyrellidae genus: arachnulacienkowsky, 1876 its phylogenetic position is a subject of some controversy. david bass and colleagues considered it to be a vampyrellid within the endomyxa clade of rhizaria, and the ssu rdna sequence isolated from an organism described as arachnula impatiens is indeed very close to that of the vampyrellid theratromyxa. the identification of this organism as arachnula has, however, been questioned; and a separate amoeba identified as arachnula by yonas isaak tekle and colleagues groups in molecular phylogenies close to the amoebozoans filamoeba and flamella. which of these isolates corresponds to that originally described by cienkowski is unresolved. notes neave, sheffield airey, ed. (1939). nomenclator zoologicus. vol. 1. london: the zoological society of london. p. 271. cienkowski l (1876). "über einige rhizopoden und verwandte organismen". arch mikrosk anat. 12: 15–50. doi:10.1007/bf02933887. s2cid 85372219. bass d, chao ee, nikolaev s, et al. (february 2009). "phylogeny of novel naked filose and reticulose cercozoa: granofilosea cl. n. and proteomyxidea revised". protist. 160 (1): 75–109. doi:10.1016/j.protis.2008.07.002. pmid 18952499. hess s, sausen n, melkonian m (february 2012). "shedding light on vampires: the phylogeny of vampyrellid amoebae revisited". plos one. 7 (2): e31165. bibcode:2012ploso...731165h. doi:10.1371/journal.pone.0031165. pmc 3280292. pmid 22355342. lahr d j g; nguyen t; lin j h; katz l a (june 2011). "comprehensive phylogenetic reconstruction of amoebozoa based on concatenated analyses of ssu-rdna and actin genes". plos one. 6 (7): e22780. bibcode:2011ploso...622780l. doi:10.1371/journal.pone.0022780. pmc 3145751. pmid 21829512.