Douglassia Explained

Douglassia is a genus of sea snails, marine gastropod mollusks in the family Drilliidae.[1]

Description

(Original description) The shell is of medium size. The whorls in the protoconch are well rounded and smooth. The postnuclear whorls show a broad concave area immediately below the summit, across which the axial ribs do not extend. The rest are convex. The base of the shell is rather short. The columella is short and shows a feeble fasciole. The aperture is rather large, deeply channeled anteriorly and posteriorly, the posterior channel being immediately below the summit. The stromboid notch is conspicuously reflected. The columellar wall is reflected as a heavy callus. The parietal wall shows a heavy callus that forms a knob at the exterior angle. The sculpture consists of strong axial ribs that extend from the anterior limit of the concave area, where they are strongest over the base, growing feebler anteriorly. Fine incremental lines are also present on the ribs and in the intercostal spaces. The body of the whorls is marked by fine spiral lirations, while the columella has strong spiral cords.[2]

Species

Species within the genus Douglassia include:

Species brought into synonymy:

References

External links

Notes and References

  1. P. Bouchet . Yu. I. Kantor . A. Sysoev . N. Puillandre . 2011 . A new operational classification of the Conoidea (Gastropoda) . . 77 . 3 . 273–308 . 10.1093/mollus/eyr017. free .
  2. https://www.biodiversitylibrary.org/item/79638#page/11/mode/1up Bartsch, P. (1934) Reports on the collections obtained by the first Johnson-Smithsonian deep-sea expedition to the Puerto Rican deep; new mollusks of the family Turritidae. Smithsonian Miscellaneous Collections, 91, 1–29, 8 pls