Habitat:
Flagellophora apelti- sublittoral to 80m North Sea & Adriatic.
Nemertoderma- sublittoral, Steinbock O 1930 fine mud at 250m.
Meara- intestine of Stichopus tremulus or in cavity of body?
Outer Appearance:
Size: Flagellophora- 0.8-1.2 mm
Meara- up to 3mm
Integument: Flagellophora & Meara - polygonal cells at base of cilia &
deeper ep. cells. Meara thick, cellular.
Nemertoderma- thick epithelial with vacuoles.
Meara- outer circ., inner longitudinal muscles,
only small adenal glands
Nervous System:
Flagellophora- internal- high brain in cross section.
Meara- neuropile at base of intestinal cells (like Nemertoderma),
swellings for 2 dorsolateral nerves- no inner nervous system
and brain less dev than Nemertoderma.
Statocyst:
2 statoliths. Statocyst muscles go out to longitudal muscles?
Steinbock O 1930 plate I.
Meara no statocyst muscles.
Meara & Nemertoderma statocyst - only sense organ.
Digestive Tract:
Flagellophora- no pharynx or mouth. "Koernerkolben" cells = mucous cells. Flagella organ.
Nemertoderma bathycola- Steinbock O 1930- refer to mouth at front end [= male pore]
Riedl RJ 1960 (citation)- defines with ventral mouth.
Karling TG 1974- shows ventral mouth.
Karling TG 1967 (citation)- illustration of sections to show cilia in digestive tract.
Karling TG 1967 (citation)- p 5,6, & 8 on gut.
Nemertoderma rubra- Faubel A 1976 (citation)- "typical pharynx simplex".
[glands and mouth are Koernerkolben?] no? but there are ones in digestive tract.
Meara- fleshy lips a little behind middle of ventral side and thickened neuropile for a sort of
psuedo-pharynx (Westblad E 1948 (citation)) intestine all through body with short
sub-lateral side ventricles. epithelial lining sort of cells- amoeboid cells
and "Koernerkolben"
Reproductive System: Faubel A 1983 (citation)- notes ciliated male tract (p. 26).
Flagellophora (female)- ovary- large bursa opening dorsally?
Meara (female)- ovary follicular- fills posterior part of bady.
Flagellophora (male)- ventral male pore- copulatory organ thickened and interal part of epithelial
layer and gland cells. no seminal vesicles- or antrum.
Meara (male)- testis follicular and fills (??) part of body. seminal vesicles thin walled (??).
Copulation by insemination - also spermatophores.
Spermatozoa- uniflagellate- see Tyler S, Rieger RM 1975 (citation) and Tyler S, Rieger RM 1977 (citation)
Hendelberg J 1977 (citation)- Nemertoderma- sp uncertain and Meara p 152, all have
middle piece and tail (uniflagellate).
both "modified spermatozoa" Franzen A 1956 (citation), Franzen A 1977 (citation)
"evolved from pimitive type of metazoan spermatozoa." helically coiled
middle piece in Meara etc- primitive single flagellum etc- differs from Acoela
see Hendelberg J 1977 (citation).
Ax 1961 (citation)- Discusses separation of this order from Acoela p 47 in diagram p 45.
Faubel A, Dorjes J 1978 (citation)- definition p 8.
"Archoophora with a digestive tract containing "Koernerkolben" cells, mouth opening simple,
nervous system epithelial aor subepithelial, statocyst with two or more statoliths, excretory
organ unknown, male genital pore in the posterior part of the body, uniflagellate spermatozoa."
Karling TG 1974 (citation)- discussion of the phylogeny of Turbellaria (See under Nermertoderma)
Rieger RM 1981 (citation)- on electron microscopy structure p 216, sperm 222, statocyst 220-221.
Doe DA 1981 (citation)- pharynges discussion.
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