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803 Micrura sp. "dark" Maculaura alaskensisa5 6 six Paired cd, td and cod six Paired cd, td and cod two Unpaired pb and dr two Unpaired pb and dr? ? six Paired cd, td and cod 6 Paired cd, td and cod5 6This study 8 Maslakova 2010 [10]The 1st 4 columns describe juvenile rudiment improvement reported inside the literature. The fifth column identifies which rudiments had been reported to invaginate (and/or shown to invaginate in figures). The final column provides the total variety of juvenile rudiments. cd--cephalic, discs td--trunk discs, dd--dorsal disc, cor--cerebral organ rudiments, pb--proboscis rudiment, cod--cerebral organ discs, dr--dorsal rudiment. aMaculaura alaskensis bears a standard planktotrophic pilidium and is integrated for comparisontrochophores. Patterns connected with the transition from planktotrophy to lecithotrophy predict its departures from typical pilidial development, which includes a bigger egg size, an accelerated developmental timeline, a reduction in feeding structures (decreased lobes and lappets), as well as the rearrangement and repurposing on the ciliary bands (from feeding to locomotion). We suggest that transition from planktotrophy to lecithotrophy explains the trochophore-like morphology of pilidium nielseni, a compelling example of evolutionary convergence on a larval physique program usually assumed to be broadly homologous.MethodsCollection of adultsWe collected a total of 129 adults of Micrura sp. "dark" in rocky intertidal places about Cape Arago in Charleston, Oregon (specifically Middle Cove, 43.305 N, 124.400 W) through or just prior to their fall/winter reproductive season. Of these, 33 have been collected from October 2013 to March 2014, 41 had been collected from July 2014 to February 2015, and 55 men and women had been collected from July 2015 to March 2016. The increases in people collected from a single spawning season for the subsequent are most likely as a result of our improved talent in locatingthem, rather than an increase in population. Fertile adults have been observed from September through February. Some have been fertile when collected, and other people (especially these collected in July and August) created gametes within the laboratory following collection. Interestingly, regardless of getting kept unfed inside the laboratory for a year, a handful of males and one female developed gametes the next reproductive season. Nonetheless, we have been unable to begin cultures with these males, and their sperm appeared somewhat lackadaisical. Micrura sp. "dark" were primarily discovered intertwined together with the dense root masses of Phyllospadix spp. expanding in shell hash, even though a number of men and women were wedged in between rocks, or in surf grass rooted in finer sand. Most folks had been collected from root masses of your most dominant surf grass, Phyllospadix serrulatus, but in addition in the root masses of P. torreyi, and possibly P. scouleri. Micrura sp. "dark" may very well be confused with two other popular co-occurring as well as undescribed lineiform nemertean species, that are equivalent in size (a number of centimeters extended) and color (pinkish, reddish or brownish). Doable misidentifications involve Lineus sp. "red," which has significantly smaller sized oocytes ( 100 m) than Micrura sp. "dark" and develops by means of a planktotrophic pilidium [45], and Lineidae gen. sp. "large eggs," a species with considerably larger oocytes ( 600 m) andHunt and Maslakova Frontiers in Zoology (2017) 14:Web page 16 ofencapsulated lecithotrophic improvement (.