Milk conchs are dispersed among the tropical waters of the Atlantic Ocean, along the coasts and islands of North, Central, and South America.

This species occurs in the Caribbean Sea; the Gulf of Mexico and the Lesser Antilles; in the Atlantic Ocean from North Carolina to East Brazil.

Specifically in Central and South America, Macrostormbus costatus have been recorded along the coasts of Paraíba state of northeastern Brazil,[3] Venezuela,[4] Panama,[5] Bermuda, Yucatan Peninsula in Mexico,[4] and Trinidad and Tobago.

[3] Te common name milk conch is derived from the milky, white interior coloration of the aperture and light cream exterior of its shell.

In contrast, other conch species, such as Aliger gigas or Strombus pugilis, are known to have various shades of pink and red tones in the aperture and various patterns or colors on the external surface.

In Panama, there is an overwhelming abundance of milk conch in seagrass meadows, where turtle and manatee grass dominates the flora.

[4] Then, as a pelagic veliger, the milk conch reaches metamorphosis to a benthic snail in approximately 26–30 days after hatching.

[4][2] The development of the proboscis (contains part of the oral cavity and radula), the loss of velar lobes, and the eyes migrating outwards occur provide morphological evidence of metamorphosis.