Conus karlschmidti (Maury, 1917)

Description

Shell of moderate size, length just twice the width; spire prominent, acute, one-fourth the total length in younger shells, less prominent in adult specimens; post-nuclear whorls about nine, of these the first two and a half are very finely coronate and the first four carinate, the subsequent spiral volutions are marked by spiral threads and by arcuate growth-lines; body whorl sharply angulate at the shoulder, from which the sides slope slightly convexly to the base, ornamented from shoulder to base by close-set spiral threads, sub-equal and numbering about thirty-five. Length of largest shell 32, greatest width 16 mm ⁽¹⁾. 

The young and relatively higher spired shells approach C. imitator Brown and Pilsbry, but differ in sculpture. This species is dedicated to Mr. Karl Schmidt, by whom it was found ⁽¹⁾. 

Localities. — (Exp'd '16) Bluff 1. Cercado de Mao; Zone E, Rio Gurabo at Los Quemados ⁽¹⁾. 

Coloration pattern ⁽²⁾

Two noninteracting patterns present. The primary (base) pattern consists of wavy, sometimes branching axial streaks that extend from the base to shoulder. The secondary pattern consists of two spiral bands that cover the anterior and posterior thirds of the last whorl, exposing the primary pattern in-between; in PRI 67562 (Fig. 23D, F), the primary pattern is weakly visible beneath the secondary pattern. The two patterns differ in the color of emitted light. Sutural ramp with radial blotches that sometimes appear to be extensions of the primary pattern over the shoulder  ⁽²⁾.

Remarks ⁽²⁾

Maury’s type specimen of C. karlschmidti is missing from the collections of the PRI (L. Skibinski, pers. comm.), so could not be compared with the shells considered here. The general shape of Maury’s figured specimen and her description, however, closely match the shells tentatively referred here to C. karlschmidti. The coloration pattern of C. karlschmidti is very similar to that of C. garrisoni sp. nov. Conus karlschmidti differs from C. garrisoni, however, in having far fewer tuberculate spire whorls and having a narrower last whorl. Among extant western Atlantic species, C. karlschmidti is similar in shell shape and coloration pattern to some specimens of C. amphiurgus Dall, 1889, though seems to lack the spiral rows of dots present in some specimens of the modern species. Puillandre et al. assigned C. amphiurgus to the subgenus Dauciconus, a designation that is followed here for C. karlschmidti ⁽²⁾.

Bibliografia Consultata

·         (1) - Maury, C. J., 1917. Santo Domingo Type Sections and Fossils. Bulletins of American Paleontology, 5 (29 )

·         (2) - Hendricks (2015) “Glowing Seashells: Diversity of Fossilized Coloration Patterns on Coral Reef-Associated Cone Snail (Gastropoda: Conidae) Shells from the Neogene of the Dominican Republic”