Eulimella cylindrata, Pimenta & Santos & Absalão, 2011

Pimenta, Alexandre Dias, Santos, Franklin Noel Dos & Absalão, Ricardo Silva, 2011, Taxonomic revision of the genus Eulimella (Gastropoda, Pyramidellidae) from Brazil, with description of three new species, Zootaxa 3063 (1), pp. 22-38 : 30

publication ID

https://doi.org/ 10.11646/zootaxa.3063.1.2

persistent identifier

https://treatment.plazi.org/id/038D87EF-FFB9-D663-9598-FDF175CF64FE

treatment provided by

Felipe

scientific name

Eulimella cylindrata
status

sp. nov.

Eulimella cylindrata View in CoL new species

Figures 26–31 View FIGURE 26–31

Diagnosis. Eulimella species with a large and inflated teleoconch, whose whorls decrease in width increment from third whorl on, resulting in an acuminate apex and an almost cylindrical shape from the fourth whorl on; teleoconch whorls with a wide spiral yellow band.

Description. Shell tall, elongate turriform, somewhat inflated, with pointed apex and abrupt decrease in width increment from third teleoconch whorl on, becoming almost cylindrical; reaching 5.3 mm in length; glossy white, some shells with a wide spiral yellow band on each teleoconch whorl, just above suture. Teleoconch with up to eight whorls rectilinear in profile. Suture shallow, rectilinear. Protoconch heterostrophic planispiral, type B with “spiral” shaped suture and ~2.25 whorls; diameter 269µm to 321µm (mean =290µm, n=4). Axial sculpture absent, except for growth lines, more evident as short, microscopic axial threads organized in spiral belts variously located near middle of earlier teleoconch whorls, and not visible in last whorls. Spiral sculpture absent. Aperture ovoid to subquadrate, inner lip barely projected into parietal region; columella arcuate, without columellar fold. Outer lip thin. Not umbilicate.

Dimensions. Holotype with 4.7 mm length / 1.2 mm (7.5 whorls); protoconch width: 297 µm, angle to shell axis: 120 o.

Type material. Holotype: MNHN 24590 About MNHN , MD 55 sta CB96; paratypes: MNHN 24591 About MNHN , MD55 sta CB96 [2]; MNRJ 19486 View Materials , MD55 sta CB77 [1]; MZSP 101568 View Materials , MD55 sta CB96 [1]; IBUFRJ 19202 , off Camburi beach, Espírito Santo state (60 m), 07/v/1986, Eq. Zoo coll.

Type locality. MD 55 sta CB96: 21º31.8’S, 40º08.7’W (295–300 m), east of Cabo de São Tomé GoogleMaps , off southeastern Brazil.

Etymology. From Latin cylindrata = in the form of a cylinder. An allusion to the subcylindrical shell shape.

Geographic distribution. Off southeast coast of Brazil.

Remarks. Eulimella cylindrata ( Figs. 26–31 View FIGURE 26–31 ) is a large species, with a few records on the southeast coast of Brazil. The species is easily recognizable by its tall and somewhat inflated shell. The general shape of the shell is quite different from all other Eulimella species from Brazil, which are conical ( E. smithii , E. rudis , E. torquata , and E. ejuncida ) or pupoid ( E. cf. calva ). In E. smithii , E. rudis , and E. torquata , there is a regular increase in the width of teleoconch whorls, resulting in a strictly conical shell. In E. cylindrata , the width of the teleoconch whorls tends to increase more gradually from the third or fourth whorl on, resulting in a shell with an acute apex (first three teleoconch whorls) and an almost cylindrical shape in the remaining teleoconch ( Figs. 26, 29 View FIGURE 26–31 ).

The most similar species from the western Atlantic is Eulimella lissa ( Verrill, 1884) ( Fig. 32 View FIGURE 32 ), which also has a somewhat inflated shell and a very similar aperture and columella. However, the width increase is more regular, not resulting in a cylindrical teleoconch as in E. cylindrata . In addition, the whorl profile of E. lissa ( Fig. 32 View FIGURE 32 ) is convex in outline, whereas in E. cylindrata it is more rectilinear.

Eulimella variabilis de Folin, 1870 and Eulimella similminuta Peñas & Rolán, 1997 , both from West Africa, have a similar subcylindrical shell shape. Eulimella variabilis has a very acuminate apex, and E. similminuta shows a very immersed protoconch. Both cases differ from E. cylindrata , whose protoconch is well visible above the first teleoconch whorl ( Fig. 28 View FIGURE 26–31 ).

The yellow spiral band on teleoconch whorls in a similar pattern to E. smithii , but in E. cylindrata , the spiral band is wider ( Fig. 26 View FIGURE 26–31 ).

Darwin Core Archive (for parent article) View in SIBiLS Plain XML RDF