The tripod fish's ventral fins and tail each have one elongated ray on which the fish perches, elevating it over the floor of the ocean.  The pectoral fins are held high over the head, curved so that is enlarged, extra-sensitive nerves can detect nearby motion, perhaps of the plankton on which the fish feeds.  It is unclear exactly how the fish feeds on these plankton, however; although the fish does face into the current when resting on its "tripod" of fins, no one has seen the fish with its mouth open while in this position.  It is equally unclear exactly how the fish moves.  It could hop or walk along the bottom on its fins, or it could launch itself from the sea floor and swim to a new position.

Tripod fish are hermaphroditic and may be able to self-fertilize in the event that another fish is not nearby, making reproduction easier a species greatly spread out in a vast environment..  The eyes of the tripod fish are tiny and largely obsolete in the face two other factors of the fish's survival: the dim visibilty of the fish's habitat and the fish's numerous, ultrasensitive neuromasts.  Fish usually have these hair-bearing sensory cells along their lateral lines, giving them a sixth sense of nearby motion.  The tripod fish, however, has these cells all over the head and body, and they are directly exposed to the open water rather than contained in mucus-filled canals.  The fish is therefore even more sensitive than most fish to the motion of nearby possible predators, such as other fish.

This trait is common to the eighteen species of bathypteroids to be found in the ocean, many of which do not have eyes at all, but rather flat sensory lobes similar to the eyespots of some vent shrimp.  The main difference between each species is the length and arrangement of the pectoral fin spines.  The different kinds of fish can also be found at different levels of the ocean, with Bathypterois longipes found at the lowest depths.  The tripod fish is the most commonly-photographed member of the genus and is found in many places, including sometimes near hydrothermal vents or cold seeps.

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