Mastacembelus kakrimensis has a blunted snout (Ref. 55095). Posterior angle of lips situated from about below the horizontal middle of the posterior nare up to its posterior edge (Ref. 55095). Upper corner of gill opening very slightly anterior to dorsal point of pectoral-fin base, both points clearly anterior to ventral point of pectoral-fin base; dorsal point of pectoral-fin base situated largely above upper corner of gill opening; gill opening closed for about half, up to entire vertical distance between the dorsal and ventral edge of the pectoral-fin base (Ref. 55095). Lateral line is yellowish-white; can be continuous in anterior part, from the head up to half the distance between head and anus; the remaining, more porsterior, part of the lateral line is always clearly discontinuous (Ref. 55095). Preopercular spines are present in small-sized specimens, but are absent in medium and large sized specimens (Ref. 55095). Preanal length negatively allometric, postanal length positively allometric, latter always smaller than former (Ref. 55095).