Convolutriloba is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

of marine

acoelomorph Acoelomorpha is a subphylum of very simple and small soft-bodied animals with planula-like features which live in marine or brackish waters. They usually live between grains of sediment, swimming as plankton, or crawling on other organisms, such ...

worms. They possess shield shaped bodies with a rounded anterior and three

caudal Caudal may refer to: Anatomy * Caudal (anatomical term) (from Latin ''cauda''; tail), used to describe how close something is to the trailing end of an organism * Caudal artery, the portion of the dorsal aorta of a vertebrate that passes into the ...

lobes, though the number may vary in mature individuals. They may have an indentation on each side of the body near the anterior end. They usually are a few millimeters to a centimeter in length and under a millimeter thick. Though they have muscles throughout their body, they move using

cilia The cilium, plural cilia (), is a membrane-bound organelle found on most types of eukaryotic cell, and certain microorganisms known as ciliates. Cilia are absent in bacteria and archaea. The cilium has the shape of a slender threadlike projecti ...

to glide. They have symbiotic algae that give them a green or brown colour. They also prey on small crustacean larvae like artemia and copepods. However they cannot survive for long periods in the dark even if they are fed. The mouth is located on the ventral surface. When feeding, they raise their front ends and fold the lateral edges of their body downward forming a funnel. Prey are trapped by lowering the body onto them. Individuals are

hermaphrodite In reproductive biology, a hermaphrodite () is an organism that has both kinds of reproductive organs and can produce both gametes associated with male and female sexes. Many Taxonomy (biology), taxonomic groups of animals (mostly invertebrate ...

s. They reproduce both sexually and asexually. They have captured scientific interest because of the various ways of agammetic

asexual reproduction Asexual reproduction is a type of reproduction that does not involve the fusion of gametes or change in the number of chromosomes. The offspring that arise by asexual reproduction from either unicellular or multicellular organisms inherit the fu ...

. During

budding Budding or blastogenesis is a type of asexual reproduction in which a new organism develops from an outgrowth or bud due to cell division at one particular site. For example, the small bulb-like projection coming out from the yeast cell is know ...

or architomy the offspring separate from the body by attaching to the substrate and tearing away. The offspring produced by sexual reproduction lack the symbiotic algae and will die unless they can pick them up within a few weeks. Like all members of the family

sagittiferidae Convolutidae is a family of acoels. It contains more than a third of all known acoel species.Turbellaria ...

they possess sagittocysts on their skin. Sagittocysts are needle like bodies 18-50 μm long that contain some secretory product. They can be extruded from the body by an associated muscle. They are believed to play a role in defence and prey capture. Ultrastructurally, they have a vesicular core surrounded by a mesh of actin filaments. Due to their rapid growth in well-lit aquariums, they are considered pests.

Systematics

* ''

Convolutriloba hastifera Convolutriloba is a genus of marine acoelomorph worms. They possess shield shaped bodies with a rounded anterior and three caudal lobes, though the number may vary in mature individuals. They may have an indentation on each side of the body near ...

'' (Winsor, 1990): The only species discovered naturally - the other three were discovered in aquaria. This species undergoes transverse fission ( architomy) near the caudal end, with a relatively undifferentiated fragment of the animal tearing away by holding onto the substrate. The smaller fragment produced by the fission grows a new head and begins moving around in a few days. * ''

Convolutriloba longifissura Convolutriloba is a genus of marine acoelomorph worms. They possess shield shaped bodies with a rounded anterior and three caudal lobes, though the number may vary in mature individuals. They may have an indentation on each side of the body near ...

'' (Bartolomaeus & Balzer, 1997) Asexual reproduction in this species occurs by architomy of the caudal end to give a small butterfly shaped piece. This piece splits longitudinally to give two daughter organisms. Thus at the end of each cycle, three new individuals are formed. * '' Convolutriloba macropyga'' (Shannon & Achatz, 2007): This species is green in colour and has a pair of indentations on either side of the head. Asexual reproduction occurs by the formation of

buds In botany, a bud is an undeveloped or embryonic shoot and normally occurs in the axil of a leaf or at the tip of a stem. Once formed, a bud may remain for some time in a dormant condition, or it may form a shoot immediately. Buds may be specia ...

facing away from the head from the caudal ends. * ''

Convolutriloba retrogemma ''Convolutriloba retrogemma'' is a reddish-brown flatworm 2 mm in length also commonly known as redbug, red planaria, rust flatworm, or simply red flatworm. It is a marine flatworm that gets energy from its endosymbiotic algae or from the ...

'' (Hendelberg & Akesson, 1988): Asexual reproduction occurs by the formation of buds from the caudal lobes. The body axis of these buds faces away from that of the mother. This results in an individual with one or more extra heads at the tips of the tails.

References

Acoelomorphs Animal genera {{acoelomorph-stub