It is found in fresh, brackish and marine waters in the West Atlantic region, ranging from New Jersey, United States, to São Paulo, Brazil, including the Caribbean and Gulf of Mexico.

[1] The opossum pipefish was formerly regarded as a subspecies of Microphis brachyurus (native to Asia and Oceania), but is now recognized as a full species by both FishBase and Catalog of Fishes.

[1] In the United States, the opossum pipefish is considered a species of concern by the National Marine Fisheries Service.

[4] Due to uncertainty about its taxonomy and vulnerability to habitat destruction, it is considered data deficient by the IUCN.

The color of the opossum pipefish is distinctive, especially in breeding adults: the upper snout and back half of the head and body is sienna brown with a series of dark red blotches on each lateral trunk ring forming a red stripe between the lateral and superior trunk ridges; there is a silver stripe on the mid-side between the lateral and inferior trunk ridges, a silver edge on the inferior trunk ridge; the lower half of the snout is bright red with a variable number of black vertical bars, and the caudal fin is also red with a central dark stripe.