Turbellarian taxonomic database

Convoluta henseni Notes

Bohmig L 1895 (citation)- description and illustration p 39-43- pelagica - also p 21.
	From plankton  6,7 degrees N. Br., 43,3 degrees W.L. Guineastrom and 12 degrees N. Br., 40,3 
		degrees W.L. North Atlantic equatorial stream.
	Length- 443-620 x 220-265 micrometers with tail. 
	Color- greyish due to fixative- no symbionts found.
	Epidermis- 6.37x3.65-4.38 micrometers high cells- not distinct - thicker layer 
		on ventral anterior side- stained dark with Bismark brown-
		formed by small rhabdites- clia lacking here
		nuclei not seen - or cells, etc. forms a sucker.  Muscle fibers in.
	Glands- vary on back and sides- at anterior end many to take place of frontal organ 
		are single cells each with 1 nucleus.  Secretion of - stained by Bismark brown.	
	Parenchyma- cells in peripheral and central.
	Muscles- dorso-ventral at anterior end around brain- not many otherwise.
	Mouth at end of antiorior 1/4 of length- pharynx simplex- short, tube-shaped.
	Brain- 2 ganglia- commissure at posterior part- no other commissure found.  Outer large nerves
		- mnany small nerves to anterior end.
	Otocyst- 14.6 micrometers on ventral side of brain- otocyst nerve- 2 outer layers- 
		1 structureless and strong outside and closely applied inside with 2 dorsal nuclei-
		Otolith with 1 nucleus.
	Reporductive Organs-
		Female gonapore at 1/4 of ant end.  Short, oblique to posterior end antrum.
			Ovary- inside testes and close together at [younger] end.  Female gonopore anterior
			to male at beginning of 2nd 3rd of body- in illustration looks like mouth antrum- not
			clear in illustration.  Nozzle- details of 36.5-58.4 micrometers composed of simple
			flat plates with holes in center by 31.8-36.5 micrometers breadth.  Stacked together.
			He lists oviducts and vasa dif "without their own walls but simply spits in 
			parenchyma".
		Male - testes from brain, lateral and ventral to ovary.  
			Penis- points into antrum- obliquely backward.  Egg shaped 73 micrometers 
				long 40-36.5 micrometers with small point.  Outer muscle layer- weakly developed.
				Circular and longitudinal muscles.  Inner epithelium 71 micrometers high, 7.3
				micrometers broad, sharply contained- stain with Bismark brown and not hem.
				Penis sheath which surrounds seminal vesicle with muscle and epithelium- muscles
				outside sheath and epithelium next to penis glandular- "does split in atrium
				muscular forms muscle of 2 muscle layers of penis and penis sheath".		
	Not adenodactyls or "gift organs".

Lohner L, Micoletzky H 1911 (citation)- compares with their Convoluta pelagica- are not same p 389-
	frontal gland p 387, on statocyst p 394-5 and p 399- penis 73 x 40 micrometers.
Meixner J 1925 (citation)- comment on p 599.
Fyfe ML 1942 (citation)- mentions sucking organs in- p 262.
Marcus E 1946 (citation)- discusses this in relationships of Macrostomidae.
Marcus E 1948 (citation)- compares colors in this to his Convoluta vexillaria p 116.
Marcus E 1949 (citation)- long description of this species and illustration good p 10-12- occurs in 
	such large numbers as to turn water green.  Includes notes that this is a flavectonic acoel.
	Collected in "canal" with plankton bail containing copepods, pluteus larvae,
	diatoms, hydromedusae, etc. note on algae in this species.  Considers this
	is distinct from Convoluta pelagica on basis of absence of concentric muscles and presense of
	cilia in the circum-buccal space in Convoluta pelagica.
	
Marcus E 1952 (citation)- mentions in description of Convoluta thauma, p 17, 20, 105.
Marcus E 1954 (citation)- mentions p 424.
Marcus EDB-R 1955 (citation)- compare with Adenopea (Convoluta) cenati- p 19, 20,21, 23.  Adenopea 
	eats this species p 23.
	
Antonius A 1968 (citation)- lists this species and on p 371 lists penis as parenchyma type without cilia.      
Dorjes J 1968 (citation)- lists.
Dorjes J,  Karling TG 1975 (citation)- Swedish Museum of Natural History.  Brazil- Tropical Atlantic,
	plankton- says very closely related to Convoluta pelagica.
       

Marcus E 1949 (citation) pg. 93-94: 'Convoluta henseni Böhm. (Figs. 1-6) hitherto only known in 6 specimens from
two supra-aequatorial localities in the tropical Atlantic was found abundantly, hundreds in one dish full of
sea-water, in the plancton of the littoral of the State of São Paulo (100 km. east and 200 km. west of
Santos).  The "sucker" of the original description is a circum-buccal cavity with shot cilia and without
glands, with a strong layer of concentric muscle fibres, tht catches the prey, chiefly Copepods (Fig. 2A). 
The enormously extensible mouth can comprehend nearly the whole of this concave field.  Large mucous glands
with cyanophilic amorphous secretion germ-cells lie outside the female ones.  The male organ is glandular, not
cuticularized.  The female pore lies close before the male pore.  The vagina is surrounded by erythrophilous
glands and opens into a wide bursa.  This has diverticles filled with sperm in its wall, that communicate with
the endocytium.  The nozzle (Fig. 6) of the bursa (0.04-0.06 mm. long)has internal and external appendages
that resemble those of Trigonostomum.  Most of the worms are coloured green by numerous algae (Fig. 1C) in the
parenchyma, that either form compact balls in the endocytium (Fig. 3B) or a thin layer under the cutaneous
muscles (Fig. 3A).  Here the algae often heap around small glands (Fig. 3A, f) not staining in the slides, the
granular bright yellow refractive contents of which seem to be excretory.  After keeping worms in abowl
without changing the water for some hours, the proportion of animals with superficial algae was bigger than in
the beginning, and after several days all had cutaneous algae.  possiblythe scarcity of food for the worms in
the dish and the consequent want of digestive waste in the parenchyma cause the algae to accumulate near the
excretory glands.  Two small yellow eye-spots lie on the level of the brain, but are not recognizable in some
individuals.
C. henseni is clearly distinct from the much bigger C. schultzei, but the only difference to C. pelagica is
the absence of concentric muscles and cilia on the circum-buccal cavity of the latter, even in sublimate-fixed
sections.  It is true tht in our formaldehyde-material of C. henseni as well as in that of the original
description these are not recognizable, but as Löhner & Micoletzky (1911a t. 19 f. 5) had well-fixed
specimens, they should have noted the short cilia shown by our material fixed with "Susa", if these were
present in C. pelagica.  The other distinctive characters between C. henseni and C. pelagica given by Löhner &
Micoletzky are all criticable.'

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