Turbellarian taxonomic database

Xenacoela Acoela Notes

History, classification schemes, and characters:

 Orsted AS 1842 (citation).
 Claparede E 1861 (citation)- description of Convoluta paradoxa and discussion of grouping.
 Uljanin W 1870 (citation)- Tribe Acoela Uljanin 1870 as in Leuckart 1871- definition p 460-1.
 Graff L v 1878 (citation)- notes Uljanin's use of term acoele.
 Jensen OS 1878 (citation)- Classification of acoela and other groups.
 Graff L v 1882 (citation)- definition.
 Wagner F v 1891 (citation)- revises Graff's monograph of 1891 and quotes his classification.
 Verrill AE 1893 (citation)- p 507-508- description of acoela but no "diagnosis".
 Graff L v 1904 (citation)- revised definition as Subclass, descusses phylogeny, and systematics.
 Bohmig L 1908 (citation)- p 3.
 Graff L v 1911 (citation)- key to genera for Order Acoela.
 Luther A 1912 (citation). p 51. Key to genera of Acoels.  Says this is a provisional arrangement.  Discussion
 		of relationship between the genera and comparison with Graff's arrangement.
 Wilhelmi J 1913 (citation)- p 11-12 classification, definition p 12, p 95 excretory system. 		
 Peebles F 1915 (citation)- suggests classification of acoela might better be based on presence or absense
 		of bursa seminalis, rather than on number of gonapores, etc. p 303, 310.
 Steinbock O 1930 (citation)- p 79 changes definition of Acoela to include Nemertodermatidae.	
 An der Lan H 1936 (citation)- classification with placement of new genera.
 Karling TG 1940 (citation)- p 230 definition (=Acoela Uljanin 1870).  Also, mentions p 223-225, 228.
 Marcus E 1947 (citation)- reference p 159.
 Marcus E 1948 (citation)- reference p 112, mentions p 126.
 Westblad E 1948 (citation)- classification, p 59 phylogeny, p 65 definition.
 Marcus E 1949 (citation)- reference p 8.
 Marcus E 1950 (citation)- reference p 6, mentions p 35
 Marcus E 1951 (citation)- lists p 7-8.
 Hyman LH 1951 (citation) -vol 2, p 127 discussion of Acoela, lists general characters.
 		p 175 embryology in Acoels, other characteristics p 128, 131, 182, 193, 203.
 Marcus E 1952 (citation)- lists references p 7.
 Marcus E 1954 (citation)- lists p 420.
 Beauchamp P de 1961 (citation)- classification.
 Hanson ED 1963 (citation)- on ciliate acoel homologies and evolutionary history of descent and origin of Metazoa.
 Lumsden RD 1966 (citation)- Excretion by Acoels. 
 Steinbock O 1966 (citation)- On divisions of Acoels, p 139.
 Dorjes J 1968 (citation)- Classification of 15 Families of Acoels.	
 Leuckart 1871 (citation)- reference to Uljanin W 1870 (citation).
 Karling TG 1974 (citation)- key p 12.  discussion of phylogeny.  Characters p 7-8.
 Tyler S 1976 (citation)- relationships as shone by ultrastructure.  Adhesive glands, p 56, not 
 		"duo-gland type" as in other Turbellaria.
 Ax P 1977 (citation)- on life cycles in p 13, 18.
 Rieger RM 1981 (citation)- on electron microscopy structure p 216, rhabdites p 219, sperm 223, 
 	statocyst 220-221.
 Boaden PJS 1981 (citation)- Oxygen requirements of acoela.
 Doe DA 1981 (citation)- pharynges discussion.
 Faubel A 1983 (citation)- a ciliated male tract in the genus Haploposthia, p 26.

Ruiz-Trillo I, Paps J, Loukota M, Ribera C, Jondelius U, Baguna J, Riutort M  2002 (citation)- "phylogenetic
analysis of DNA sequences from the myosin heavy chain type II (myosin II) gene from a large set of
metazoans, including acoels and nemertodermatids."  Evolutionary significance.  

Reuter M, Raikova OI, Gustafsson MKS 2001 (citation)- Phylogeny, neurons, muscles.  Acoela and Nemertodermatida
studies of neuroanatomy.  Species used include:
  Catenulida  
     Stenostomum leucops Duges 1828
  Macrostomida
     Macrostomum lineare Muller 1774
  Acoela
     Anaperus biaculeatus
     Childia groenlandica Levinsen 1879
     Faerla glomerata Westblad 1942
     Paraphanostomum crassum Westblad 1942
     Avagina incola Leiper 1902
  Nemertodermatida
     Nemertoderma westbladi Steinbock 1938
     Mera stichopi Westblad 1949

Reuter M, Raikova OI, Jondelius U, Gustafsson MKS, Maule AG, Halton DW 2001 (citation)- Immunocytochemical study
of Faerlea glomerata, Avagina incola, and Paraphanostoma crassum to look at the organization of the Acoela
nervous system.

Littlewood DTJ, Olson PD, Telford MJ, Herniou EA, Riutort M 2001 (citation)- Reviews recent molecular systematics
on Acoela, Nemertodermatida, Catenulida and Rhabditophora,  EF1 analysis and its limitations, etc.

Gschwentner R, Ladurner P, Nimeth K, Rieger R 2001 (citation)- stem cells (neoblasts) analysis in stages of
cell cycle in Convolutriloba longifissura.  Relation to reproduction and regeneration.  Importance in
phylogenetic relationships.

Akesson B, Gschwentner R, Hendelberg J, Ladurner P, Mueller J, Rieger R 2001 (citation)- "new pattern of
reproduction in the Acoela has prompted us to review the various ways by which asexual
reproduction occurs in the group."  Type of fission of Convolutriloba longifissura is described. 
Evolutionary significance.

Tyler S, Hyra GS 1998 (citation)- muscle patterns in Acoela, including the following taxa:
   Anaperus, Childia groenlandica, Convoluta pulchra, Mecynostomum, Otocelis, Paedomecynostomum bruneum,
   Paratomella , Pseudaphanostoma.

Berney C, Pawlowski J, Zaninetti L 2000 (citation)- "Elongation factor 1-alpha sequences do not support an early
divergence of the Acoela".  Following species used: Convoluta roscoffensis, Crenobia alpina, Girardia
tigrina, Leptoplana tremellaris, Prostheceraeus vittatus, Schmidtea polychroa. 

Ruiz-Trillo I, Riutort M, Littlewood DTJ, Herniou EA, Baguna J 1999 (citation)- "Acoel flatworms: earliest
extant bilaterian metazoans, not members of Platyhelminthes".

Raikova OI, Reuter M, Kotikova EA, Gustafsson MKS 1998 (citation)-  5-HT immunoreactivity in Acoela, brain
analysis.  Species used: Anaperus biaculeatus, Childia groenlandica, Actinoposthia beklemischevi, and
Mecynostomum sp.

Lundin K 1997 (citation)-  "ultrastructure of the epidermal ciliary rootlets and associated structures in
species of the Nemertodermatida and Acoela".  Species used: Meara stichopi, Nemertoderma westbladi,
Nemertoderma cf. bathycola, Convolutriloba retrogemma, Childia groenlandica, Paraphanostoma submaculatum,
Haploposthia virdis.

Gradinger R, Schnack-Schiel SB 1998 (citation)- "sympagic acoel turbellarians" effect of Antarctic Polar ice
and salinity on mortality compared to species of copepods.

Reuter M, Raikova OI, Gustafsson MKS 1998 (citation)- brain of Acoela a common flatworm type?  Immunocytochemical
study (FMRF-amide) of nervous system of four species: Anaperus biaculeatus, Childia groenlandica,
Actinoposthia beklemischevi and Mecynostomum sp.

Katayama T, Yamamoto M, Wada H, Satoh N 1993 (citation)- Phylogeny of Acoels "inferred from partial 18S rDNA
sequences".  Species used in analysis: Convoluta naikaiensis Yamasu 1982, Amphiscolops sp. Yamasu,
Notoplana koreana Kato 1937, Planocera multitentaculata Kato 1944, Stylochus orientalis Bock 1913,
Pseudostylochus obscurus (Stimpson 1857), Stylochoplana pusilla Bock 1924, Thysanozoon brocchii (Risso
1818), Dendrocoelopsis lactea Ichikawa & Okugawa 1958 and Dugesia japonica Ichikawa & Kawakatsu, 1964.

Ehlers U (citation)-"Frontal glandular and sensory structures in Nemertoderma (Nemertodermatida) and
Paratomella (Acoela): ultrastructure and phylogenetic implications for the monophyly of the
Euplathelminthes".  Nemertoderma sp. B, and Paratomella rubra used.

Raikova OI 1991 (citation)- fine structure, "nervous system and ciliary receptors of acoelan turbellarians". 
Species considered: Actinoposthia beklemischevi, Anaperus biaculeatus, Aphanostoma virescens, Haploposthia
opisthorchis.

Bedini C, Lanfranchi A 1991 (citation)- Electron microscopy study of "central and peripheral nervous system of
Acoela"

Winsor L 1990 (citation)- Key to "free-living" marine turbellaria of north Queensland, Australia.  Also, new
species and taxonomic revisons.  Key to free-living acoels for Australia.  Species and taxa include:
     Waminoa litus
     Convolutriloba Henelberg and Akesson 1988
     Convolutriloba hastifera
     Convolutriloba japonica (Kato 1951)
     Convolutriloba cf. retrogemma
     Amphiscolops
     Amphiscolops australis
     Wulguru cuspidata 
     Heterochaerus sargassi (Hyman 1939)
     Heterochaerus australis Haswell 1905
     

Reuter M, Lehtonen M, Wikgren M 1988 (citation)-  "Immunocytochemical evidence of neuroactive substances in
flatworms of different taxa - a comparison."  Species Archiloa unipunctata, Gyratrix hermaphroditis,
Microdalyellia fusca, Polycelis nigra, Promesostoma marmoratum, Typhloplana viridata.

Smith JPS, Tyler S 1985 (citation)- "The acoel turbellarians: kingpins of metazoan evolution or a specialized
offshoot?"  Look at ultrastructural characters (body wall, parenchyma, digestive tract).  "....it appears
that acoels are derived, and cannot logically be fitted into any of the current theories of interphyletic
relationships, either as models of primitiveness or as reduced coelomates.  Instead, the Nemertodermatida,
sister group to the Acoela, and the Catenulida appear more primitive, and consideration of these groups for
phylogenetic schemes is more likely to bear fruit."  Species of Acoela include:
     Diopisthoporus cf. longitubus
     Diopisthoporus sp. (= Diopisthoporus gymnopharyngeus Smith JPS, Tyler S 1985 (citation))
     Hesiolicium inops
     Convoluta convoluta
     Convoluta sp. nov.  (= Convoluta pulchra Smith JPS, Bush L 1991 (citation)) 
     Oxyposthia praedator
     Oligochoerus limnophilus
     Paedomecynostomum sp.
     Paramecynostomum diversicolor
     Anaperus biaculeatus
     Anaperus sp.
     Kuma sp.
     Philactinoposthia sp.
     Otocelis luteola

Faubel A, Regier S 1983 (citation)- "Anatomy and taxonomy of new Acoela (Turbellaria) from the sublittoral of the
northern North Sea."

Bush LF 1981 (citation)-  Marine flora and fauna of the northeastern United States. Turbellaria: Acoela and
Nemertodermatida.

Powell EN 1979 (citation)- "Biochemical adaptations to long-term sulfide stress present in the interstitial
metazoans of the sulfide system."

Mamkaev YuV, Markosova TG 1979 (citation)- "Electron microscopic studies of the parenchyma in some representatives
of the Acoela."  Species studied include:
     Oxyposthia praedator
     Convoluta convoluta
     Anaperus biaculeatus
     
 [translated summary "...differentiation of the secretory cells of the epidermal glands in the parenchyma,
and the presence of muscular and nervous elements in the epidermal layer, leads to the conclusion that in the
Acoela there is a close interrelation between the parenchyma and the epidermis, and that phagocytoblast and
kinoblast are still poorly separated."]

Mamkaev YuV, Kostenko AG 1991 (citation)- "On the phylogenetic significance of sagittocysts and copulatory
organs in acoel turbellarians."

Raikova OI 1989 (citation)- Ultrastructure of the nervous system and the sensory receptors of acoel turbellarians.
[In Russian]"

Carranza S, Baguna J, Riutort M 1997 (citation)- "Are the Platyhelminthes a monophyletic primitive group? An 
assessment using 18S rDNA sequences."  Looks at Rhabditophora, Acoela, Catenulida.  Species of Turbellaria
used include the following:  Crenobia alpina, Dendrocoelum lacteum, Monocelis lineata, Archiloa rivularis,
Geocentrophora sp., Mesocastrada sp., Nemertinoides elongatus, Urastoma sp., Macrostomum tuba, Microstomum
lineare, Discocelis tigrina, Planocera multitentaculata, Stenostomum leucops, Convoluta pulchra, Convoluta
naikaiensis.  New sequences reported for many of these species.

Reuter M, Lehtonen M, Wikgren M 1988 (citation)- "Immunocytochemical evidence of neuroactive substances in
flatworms of different taxa--a comparison."  Species studied:  Acoela sp., Archiloa unipunctata, Polycelis
nigra, Microdalyellia fusca, Promesostoma marmoratum, Typhloplana viridata, Gyratrix hermaphroditus.

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