Licnophora

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Licnophora
Drawing of Licnophora (originally Trichodina) auerbachii by Cohn (1866), showing attachment disk (a), mouth (m), and adoral zone (p).
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Licnophora

Claparède, 1867

Licnophora is a genus of ciliates in the family Licnophoridae. They typically have an hourglass-like shape and live as ectocommensals on marine animals.

Description[edit]

The cell body of most Licnophora species is shaped like an hourglass. The oral region is on one end, and is surrounded by specialized cilia (the adoral zone of oral polykinetids). The other end contains a circular attachment disk (or basal disk) that is used to attach to the substratum, a feature unique to licnophorids, although they can also be free-swimming.[1]

Licnophora are ectocommensals, living attached to different kinds of marine animals, including gastropods, bivalves, polychaetes, and seahorses. One species was found attached to algae.[2] Heavy infections of Licnophora auerbachii have been known to damage the eyes of the scallop Chlamys opercularis, by abrading the animal tissue when they attach to it.[3]

Systematics[edit]

The genus Licnophora was first defined by René-Édouard Claparède in 1867. He transferred the species Trichodina auerbachii Cohn, 1866 to this genus, and also named a new species L. cohnii in honor of Ferdinand Cohn.[4] The genus was formerly classified as a heterotrich.[5] More recent classification systems place it within the Spirotrichea, because of evidence from molecular phylogenetics and some morphological features of the macronucleus.[1][6] However, another analysis has found that it is an "isolated branch" within the subphylum Intramacronucleata that is most closely related to the Spirotrichea, Armophorea, and Clevelandellidae.[7]

Etymology[edit]

The name means "fan-bearer".[4]

List of species[edit]

As of 2000, eleven species of Licnophora have been described:[2]

  • Licnophora auerbachii (Cohn, 1866)
  • Licnophora bassoni L. L. van As & J. G. Van As, 2000
  • Licnophora biecheleri Villeneuve-Brachon, 1940
  • Licnophora bullae Dustin, 1915
  • Licnophora chattoni Villeneuve-Brachon, 1939
  • Licnophora cohnii Claparéde, 1867
  • Licnophora conklini Stevens, 1904
  • Licnophora hippocampi Meng and Yu, 1985
  • Licnophora limpetae Van As, Van As and Basson, 1999
  • Licnophora lyngbycola Fauré-Fremiet, 1937
  • Licnophora macfarlandi Stevens, 1901

References[edit]

  1. ^ a b Lynn, Denis H. (2008). The ciliated protozoa : characterization, classification, and guide to the literature. New York: Springer. p. 347. ISBN 9781402082382. OCLC 272311632.
  2. ^ a b Van As, Liesl L.; Van As, Jo G. (2000). "Licnophora bassoni sp. n. (Ciliophora: Heterotrichea) from South African Turban Shells (Gastropoda: Prosobranchia)" (PDF). Acta Protozoologica. 39: 331–335.
  3. ^ Harry, Owen G. (1980). "Damage to the eyes of the bivalve Chlamys opercularis caused by the ciliate Licnophora auerbachii". Journal of Invertebrate Pathology. 36 (3): 283–291. doi:10.1016/0022-2011(80)90037-3.
  4. ^ a b Claparède, E. (1867). "Sur les Licnophora, nouveau genre de la famille des Urcéolariens (infusoires ciliés)". Annales des Sciences Naturelles, Zoologie (in French). ser. 5 t. 8 (1867): 30–34.
  5. ^ Fauré-Fremiet, E. (1937). "Licnophora lyngbycola, a New Species of Infusorian from Woods Hole". Biological Bulletin. 72 (2): 212–216. doi:10.2307/1537255. JSTOR 1537255.
  6. ^ Lynn, Denis H.; Strüder-Kypke, Michaela (November 2002). "Phylogenetic position of Licnophora, Lechriopyla, and Schizocaryum, three unusual ciliates (phylum Ciliophora) endosymbiotic in echinoderms (phylum Echinodermata)". The Journal of Eukaryotic Microbiology. 49 (6): 460–468. doi:10.1111/j.1550-7408.2002.tb00229.x. ISSN 1066-5234. PMID 12503681.
  7. ^ Miao, Miao; Song, Weibo; Clamp, John C.; Al-Rasheid, Khaled A.s.; Al-Khedhairy, Abdulaziz A.; Al-Arifi, Saud (2009-05-01). "Further Consideration of the Phylogeny of Some "Traditional" Heterotrichs (Protista, Ciliophora) of Uncertain Affinities, Based on New Sequences of the Small Subunit rRNA Gene". Journal of Eukaryotic Microbiology. 56 (3): 244–250. doi:10.1111/j.1550-7408.2009.00391.x. ISSN 1550-7408. PMID 19527351. S2CID 882895.