Here's an article listing the many sensory systems human beings have beyond the classic "five":More Than Five Senses
"Touch," for example, is far from a simple, unified sense. We have separate nerves for temperature, itching, pressure, and pain. I do think it's a stretch, though, to call perception of hunger, thirst, and time "senses." And what about chemoreceptors? "Chemoreceptors: These trigger an area of the medulla in the brain that is involved in detecting blood born [sic: "blood-borne"?] hormones and drugs. It also is involved in the vomiting reflex." If we're not consciously aware of this perception, only of its results (e.g., vomiting) is it a "sense"?
Still, there are plenty to get on with in constructing aliens with different dominant senses from ours. Most human beings have sight or hearing as the dominant sensory mode. A smaller minority focuses on touch. Suzette Haden Elgin's "Gentle Art of Verbal Self-Defense" system includes a lot of material on sensory modes:
What kind of environment would an alien evolve and live in to have magnetism, electricity, tremor-sense, or echolocation as its dominant sense? And what about telepathy? If a sapient race communicates telepathically, they probably live in an environment where sight and hearing don't operate efficiently. Would a telepathic species have any reason to develop spoken language? Probably not, but as they became technologically advanced, one would think they'd invent a written language for archives and long-distance communication. Unless maybe they "store" memories in crystals or some other matrix and access them by touch. Could they use similar devices to amplify mental signals and send messages without anything we'd recognize as language?
If so, imagine the difficulty of making contact with them, conveying the concept of "language," or even convincing them we're intelligent. (Unless they have the ability to probe the minds of non-telepathic sentients.)
Margaret L. CarterCarter's Crypt