This eukaryotic unicellular marine alga (Calcidiscus leptoporus), is a coccolithophore which occurs in two phases: haploid and diploid. The haploid phase has two undulipodia and between them, a haptonema. The long lines in this LM photo are the undulipodia (aka bacterial flagella), and the shorter line with the knob at the end, is the haptonema, which is characteristic of this group, the Haptophytes.
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<span class="int-own-work" lang="en">Own work</span>