
Phylum Cycliophora feed on bacteria or bits of food dropped from host only 3 species can regenerate by internal budding first discovered in 1995 on the mouthparts of the àcontinually produces new funnels by internal asexual Norway lobster budding very small; less than half mm; 0.35 - 0.10 mm as the new funnel develops the old buccal funnel disingegrates all species symbiotic on crustaceans the new funnel then emerges through the trunk and takes the place of the old one more recently have been found on the American Lobster and European lobster Life cycle Body Form complex life cycle with 3 basic life stages saclike, bilateral body à alternation of generations with no body cavity, acoelomate 1. asexual feeding stage back end has short stalk with adhesive disc by which dominant stage is sessile, solitary feeding stage they attach to their host neither male nor female cellular epidermis surrounded by cuticle 350 microns; saclike Digestive System attached to host by short stalk with an adhesive disc at the end anterior feeding organ is a ciliated buccal funnel sessile feeding stage is asexual cilia around mouth moves food into esophagus 2. sexual stages esophagus leads to à U shaped gut à anus Animals: Phylum Cycliophora; Ziser Lecture Notes; 2015.10 1 Animals: Phylum Cycliophora; Ziser Lecture Notes; 2015.10 2 the onset of the sexual stage is believed to be female matures and breaks free triggered by imminent molting of the lobster host. briefly free-swimming, then attaches to lobster mouthparts the feeding form produces either male or female progeny which develop internally within the female form a new dispersive larva develops; resumably from a fertilized egg dwarf male the female progressively degenerates and the a simple sac mature larva escapes nonfeeding; no mouth, digestive system or eventually the larva settles and anus metamorphoses into an asexual feeding stage two reproductive organs contain stores of sperm Evolutionary Relationships two penile organs taxonomy is controversial; molecular data indicates it may be related to rotifers and acanthocephala matures inside feeding stage before breaking free and becoming attached to another feeding stage that is in the process of producing a female reproductive individual mechanism of fertilization is unknown female also develops inside a feeding form contains a single egg Animals: Phylum Cycliophora; Ziser Lecture Notes; 2015.10 3 Animals: Phylum Cycliophora; Ziser Lecture Notes; 2015.10 4 .
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