Douglassia
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''Douglassia'' is a
genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...
of
sea snail Sea snails are slow-moving marine (ocean), marine gastropod Mollusca, molluscs, usually with visible external shells, such as whelk or abalone. They share the Taxonomic classification, taxonomic class Gastropoda with slugs, which are distinguishe ...
s, marine
gastropod Gastropods (), commonly known as slugs and snails, belong to a large Taxonomy (biology), taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, freshwater, and fro ...
mollusk Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000  extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The ...
s in the
family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...
Drilliidae The Drilliidae are a taxonomic family of small predatory sea snails with high-spired shells. They are classified as marine gastropod mollusks in the superfamily Conoidea. This family has no subfamilies. It consists of about 30 genera and approx ...
.


Description

(Original description) The shell is of medium size. The
whorl A whorl ( or ) is an individual circle, oval, volution or equivalent in a whorled pattern, which consists of a spiral or multiple concentric objects (including circles, ovals and arcs). In nature File:Photograph and axial plane floral diagra ...
s in the
protoconch A protoconch (meaning first or earliest or original shell) is an embryonic or larval shell which occurs in some classes of molluscs, e.g., the initial chamber of an ammonite or the larval shell of a gastropod. In older texts it is also called " ...
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 Lucius Junius Moderatus Columella (, Arabic: ) was a prominent Roman writer on agriculture in the Roman Empire. His in twelve volumes has been completely preserved and forms an important source on Roman agriculture and ancient Roman cuisin ...
is short and shows a feeble fasciole. The
aperture In optics, the aperture of an optical system (including a system consisting of a single lens) is the hole or opening that primarily limits light propagated through the system. More specifically, the entrance pupil as the front side image o ...
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 Sculpture is the branch of the visual arts that operates in three dimensions. Sculpture is the three-dimensional art work which is physically presented in the dimensions of height, width and depth. It is one of the plastic arts. Durable sc ...
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.


Species

Species within the genus ''Douglassia'' include: * '' Douglassia antillensis'' Fallon, 2016 * '' Douglassia bealiana'' Schwengel & McGinty, 1942 * '' Douglassia curasub'' Fallon, 2016 * '' Douglassia enae'' Bartsch, 1934 * '' Douglassia minervaensis'' Fallon, 2016 * '' Douglassia moratensis'' Fallon, 2016 ;Species brought into synonymy: * ''Douglassia nodosa'' Nowell-Usticke, 1969: synonym of '' Splendrillia interpunctata'' (E. A. Smith, 1882)


References


Tucker, J.K. 2004 ''Catalog of recent and fossil turrids (Mollusca: Gastropoda)''. Zootaxa 682:1-1295
*


External links


WMSDB - Worldwide Mollusc Species Data Base: family Drilliidae
{{Taxonbar, from=Q5302195 Drilliidae Gastropod genera