Beneden E van 1870 (citation)-
Dorjes J 1968 (citation)- p 115 definition. p 116 discussion and historical good summary.
"Throughout elongated slim, colorless or pigmented forms with male genital pore lying subterminally
at posterior end. The copulatory organ circular to globe shaped in appearance. The vesicle wall
and the contour of the reproductive pore often appear as 2 concentric circles. Copulatory organ
is formed of a proximal sperm storing and a distal cellular part with the ? of a penis and a
gland. In a few species delicate cuticularized needles arrayed in a cone are present in the
passatge. Rhabdites lacking or very small and lying dispursed. Body more or less dorso-ventrally
flattened."[Bush translation] Type Mecynostomum Van Beneden
1. Mecynostomum van Beneden 1870
2. Paedomecynostomum Dörjes, 1968
3. Paramecynostomum Dörjes, 1968
4. Philomecynostomum Dörjes, 1968
5. Postmecynostomum Dörjes, 1968
6. Pseudomecynostomum Dörjes, 1968 refers to Pseudmecynostomum in rest of article.
p 117 key:
1. Seminal bursa lacking---------------------------------------------Mecynostomum
1. Seminal bursa without cellular, muscular or
cuticular appendage----------------------------------------------2
2. Seminal bursa without cellular, muscular or cuticular
appendage---------------------------------------------------Pseudomecynostomum
2. Appendage cellular, muscular or cuticular--------------------3
3. Appendage cellular-------------------------------------------------Postmecynostomum
3. Appendage muscular-------------------------------------------------Paramecynostomum
3. Appendage cuticular------------------------------------------------4
4. Appendage from matrix cells in ? basal section weakly
cuticularized secretion is layered. Bursal seminalis
well developed------------------------------------------Philomecynostomum
4. Well developed nozzle present. Seminal bursa indistinct or
parenchymatous------------------------------------------Paedomecynostomum
Karling TG 1974 (citation)- in list p 9.
Ehlers U, Doerjes J 1979 (citation)- list p 60.
Faubel A, Regier S 1983 (citation)- p 2 lists, and gives revision of genus p 11. Pseudmecynostomum.
New genus Eumecynostomum.
Notes from synonyms
Notes for Acoela Childiidae
Dorjes J 1968 (citation)- p 110 definition, list of genera, discussion p 110-111, key to genera p 79. Type genus CHildea. p 101 says Otocelis species may go here eventually ? "Acoels with well developed copulatory organs. Cone-shaped penis stylet always present. This formed either from cuticularized or muscular elements, however never invaginated into the seminal vesicle. The latter can be lacking. Male reproductive pore variable in position. Mouth opening ventral." Type genus Childea Graff 1911- 10 genera and 36 species. Short discussion. Key: 1. Seminal bursa lacking ----------------------------------------2 1. Seminal bursa presnet ----------------------------------------5 2. with 2 copulatory organs -------------------------------------Childea 2. with 1 copulatory organ --------------------------------------3 3. Colored. Male antrum lacking ---------------------------------Paraproporus 3. Uncolored. Male antrum present ------------------------------4 4. Male antrum long, tube-shaped, ciliated. Penis cuticularized by discharge of matrix cells --------------------------------Atriofronta 4. Male antrum short. Penis constructed of large, cuticularized stylet needles. ---------------------------------------------Actinoposthia 5. Nozzle cuticularized -----------------------------------------6 5. Bursa without a cuticularized nozzle--------------------------7 6. Four (4) copulatory organs -----------------------------------Tetraposthia 6. A single male copulatory organ -------------------------------Philactinoposthia 7. Seminal bursa without an evident (light neuro?) ducctus spermaticus. Outer muscle layers with outer circular and inner longitudinal muscles ---------------------------------Pseudactinoposthia 7. Seminal bursa with cellular or muscular spermatic duct. Lacking this, then the outer muscle layer formed of outer longitudinal and inner circular muscles----------------------8 8. Outer muscle layer of outer longitudinal and inner circular muscles--------------------------------------------Paraphanostoma 8. Outer muscle layer of outer circular and inner longitudinal muscles -----------------------------------------------------9 9. Ductus spermaticus muscular, invaginated into the bursa seminalis and divided caudally-------------------------------Pelophila 9. Ductus spermaticus cellular, anterior directed-----------------Proactinoposthia Karling TG 1974 (citation)- in list p 9. Faubel A 1976 (citation)- lists p 42. Ehlers U, Doerjes J 1979 (citation)- in discussion of Otocelidae genera p 48, 70.
Notes for Acoela Childiidae
Hooge MD 2001 (citation) - "Childia groenlandica posesses not only a unique pattern of musculature (Figs. 6,7) but the layering of these muscles is also unique among acoels in that the relative positions of the subepidermal body-wall muscle fibers are reversed, with longitudinal muscle fibers lying outside of inner circular fibers, a condition first recognized by Luther (1912) (citation). These features, along with its unusual paired male copulatory apparatus, suggests that the Childiidae as it is presently known is polyphyletic. Additional endorsement for polyphyly comes from preliminary ultrastructural and immunocytochemical studies that sugges the sclerotized copulatory structures used to unite the group are nonhomologous among several taxa (Raikova et al., 2001) (citation). I propose leaving Childia groenlandica as the sole occupant of Childiidae and creating a new family, Actinoposthiidae, for the other childiid taxa." Hooge MD, Haye P, Tyler S, Litvaitis MK, Kornfield I 2002 (citation)- Phylogenetic relationships using 18S rDNA, and morphological characters of sperm and body-wall musculature.- "The unique nature of C. groenlandica led Hooge 2001 (citation) to remove the other species in the Childiidae to a new family, the Actinoposthiidae. The gene tree supports this taxonomic revision; however, some further changes may be necessary, inasmuch as members of the actinoposthiid genus Paraphanostoma also have circular muscles (Westblad, 1942) (citation)."
Notes for Acoela Childiidae
Tekle YI, Raikova OI, Ahmadzadeh A, Jondelius U 2005 (citation) - Found the monophyly of Childia and Paraphanostoma to be supported by molecular and morphological data. Paraphanostoma synonymized with Childia; all former members of Paraphanostoma transferred to Childia.Return to Acoela Childiidae