Architectonica nobilis

Architectonica nobilis, common name the American sundial, is a species of sea snail, a marine gastropod mollusk in the family Architectonicidae, which are known as the staircase shells or sundials.^[1]

Architectonica nobilis
Shell of Architectonica nobilis
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
Family:	Architectonicidae
Genus:	Architectonica
Species:	A. nobilis
Binomial name
Architectonica nobilis Röding, 1798
Synonyms
Architectonica granulata (Lamarck, 1816) junior subjective synonym † Architectonica sexlinearis (E. T. Nelson, 1870) junior subjective synonym Architectonica valenciennesii Mörch, 1859 junior subjective synonym Architectonica wroblewskyi Mörch, 1875 Solarium granosum Valenciennes, 1832 junior subjective synonym Solarium granulatum Lamarck, 1816 Solarium ordinarium E. A. Smith, 1890 Solarium quadriceps Hinds, 1844 junior subjective synonym † Solarium sexlineare E. T. Nelson, 1870 junior subjective synonym Solarium verrucosum R. A. Philippi, 1849 junior subjective synonym

The subspecies Architectonica nobilis karsteni Rutsch, 1934: is a synonym of Architectonica karsteni Rutsch, 1934 (original rank).

Description

The shell exhibits a whitish-yellow ground color. A series of red-brown spots marks the area immediately below the suture. The color pattern is completed by paler spots distributed across both the spiral cords and the interspaces, both above and below the base.

(Original description of Solarium quadriceps in Latin) The shell is orbicular-discoidal. The numerous flattened whorls are girdled in four rows with various width. The cords are furnished with quadrate, flattened, and approximate tubercles. The lower cord is larger and is painted red along with the upper one. The shell is swollen at the base, and the median area is radiately folded. The umbilicus is wide-open and is encircled by large brown crenations. The narrow umbilical area is smooth.^[2]

(Original description of Solarium ordinarium in Latin) The shell is orbicular-conoidal, depressed, and moderately umbilicated. It is whitish or tinted with lilac, and punctated with red. There are 5 whorls, which are scarcely somewhat convex. They are girdled with five obliquely granose ridges. The body whorl is acutely angled at the periphery. It is generally lilaceous, concentrically grooved and girdled. The girdle around the umbilicus is the largest and strongly crenated, while the remaining girdles are also more or less crenulated or sub-quadrately granulated. The aperture is trapeziform and is bi-channeled at the columella.^[3]

Distribution

This marine species has a wide distribution and can be found in sand and shallow waters off the coast of North, Central and South America:; also off Spain.