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Fig.19.Rotiferdormanteggs;1-Ascomorphaovalis;2-Gastropusstylifer;3-Ascomorpha
saltans;4-Synchaetalongipes;5-Synchaetalakowitziana;6-Synchaetapectinata;
7-Ploesomatruncatum;8-Ploesomahudsoni;9-Filinianovaezealandiae
(afterKOSTE1978,withpermission)
perhapsitservessomeother,sofarunknown,function.Theeggsize,shape,col-
ourandornamentationarespecies-specific(POURRIOTandSNELL,1983).Dormant
eggsareresistanttodesiccation,lowtemperaturesanddigestiveenzymesof
apredator’sintestine.Dormanteggshatchintoamicticfemales.
Sexualreproductionisfrequentlyobservedinartificialcultures.Someclones,
havingpassedthroughanumberofgenerations,maylosetheabilitytoreproduce
sexually.PILARSKA(1972)observedthatmicticfemales,whichhadalreadybegun
producinghaploideggs,didnotlayfertilisedeggsinspiteofhavingcopulated.
InBrachionusrubens,dormanteggsareproducedonlybythosemicticfemales
whichhadcopulatedbeforetheirfirsteggswerelaid.
Dormanteggsseemtobeveryimportantinrotiferdispersal;theyarecarried
awaybywater,windoranimals.Theymayalsobeofcertainimportanceinpalae-
olimnology(POURRIOTandSNELL1983).Boththeperiodofdormancyandthecue
releasingitandtriggeringdevelopmentarespecies-specific.Dormanteggsmay
beregardedasanadaptationtoanunpredictablehabitatandserveasa“gene
bank”(RICCI1992).
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