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I analyze the K2 and TESS data taken in 2016, 2019 and 2021 of the symbioticX-ray binaries GX 1+4 and IGR J16194-2810. GX 1+4 consists of a pulsaraccreting from a red giant companion in a 1160 days orbit. Since 1984, thepulsar has shown a continuous spin-down rate of $\dot{P}$=-0.1177(3) mHZ/yr. Ireport the detection of the spin period at an average value of 180.426(1)seconds as observed with the K2 mission and confirm that the spin periodcontinues to increase at a rate of $\sim$1.61$\times$10$^{-7}$ s/s. The K2 andhard X-rays, as observed with Swift/BAT, varied in tandem, in agreement withother authors who proposed that the optical light arise from reprocessed X-rayemission.  In the case of IGR J16194-2810, the X-ray and optical spectroscopy have beeninterpreted as arising from a neutron star accreting from a M2 III red giantcompanion. Its orbital period is unknown, while I report here the detection ofa modulation with a period of 242.837 min, interpreted as the neutron star spinperiod. IGR J16194-2810 is thus the second symbiotic X-ray binary where thespin period is detected in optical wavelengths. This period, however, was onlydetected during the TESS observations of Sector 12 in 2019. The non-detectionof this modulation during the observations of Sector 39 in 2021 is perhapsrelated with the orbital modulation, i.e. a low inclination of the orbit.

K2 & TESS observations of symbiotic X-ray binaries: GX 1+4 and IGR J16194-2810