**8. Conclusion**

On Mars, at Gale Crater, a past environment favourable to life and for a broad span of geological time, has been discovered by various authors [1, 2, 49], as well as the occurrence of many micro, meso and macrostructures similar to terrestrial stromatolites, microbialites and algae [18, 50]. All these items are suggestive of possible biological parallels between Earth and Mars. In the present paper, we show morphological and morphometric analyses of the whitish millimetric shapes (we nicknamed "rice grains"), detected by the rover Curiosity at sols 809 and 880 (Mojave target) in the lacustrine Murray Formation (attributed to pseudomorph crystals of sulfate by previous Authors, [7]). Specimen which are incompatibile to Gypsum, Jarosite, or Feldspar crystals, but show a high shape affinity to life forms such as the Euglenoids. Hence, the microstructures investigated in this study, together with chemical and mineralogical converging data of the outcropping where they are embedded, suggest the possible existence of microbial, and/or little more complex life forms, in the past history of Mars.
