Original Description of Orthaulax portoricoensis by Hubbard, 1921, p. 146:
- "Under this heading are included all the large Strombus-like internal molds, which are among the most abundant forms to be found in the Quebradillas limestone. One of these internal molds was figured by Semmes, in his report on the San Juan District, as Strombus, species indet. The internal molds, taken by themselves, are generically indeterminate, but resemble the molds of a large Strombus. Fortunately, a few of these internal molds were found with portions of the external mold adhering to the specimens, which proves beyond a doubt that these large shells belong to the genus Orthaulax. They attain a size much greater than any species of Orthaulax yet known."
Stratum typicum: "Quedbradillas limestone, Los Puertos limestone. Characteristic of the Quebradillas of the entire north coast of Porto Rico, as shown by the collections of Berkey and Semmes."
- B. Hubbard, 1921. Tertiary Mollusca from the Lares District, Porto Rico. Scientific survey of Porto Rico and the Virgin Islands, vol. 3, pt. 2, pp. 79-164, pls. X-XXV, New York Acad. Sci.