Neverita delessertiana

Hülsken, Thomas, Clemmensen, Marina & Hollmann, Michael, 2006, Neverita delessertiana (Récluz in Chenu, 1843): a naticid species (Gastropoda: Caenogastropoda) distinct from Neverita duplicata (Say, 1822) based on molecular data, morphological characters, and geographical distribution, Zootaxa 1257, pp. 1-25 : 18

Neverita delessertiana (Récluz in Chenu, 1843)

Natica delessertiana Récluz in Chenu, 1843, Natica pl. 4, figs. 5,5; 6,6 [figures only; no description]. See Figs. 1 A­H.

+ Natica fossata Gould, 1847 , p. 263; Gould 1862, p. 202.

+ Natica texasiana Philippi, 1849 ; Philippi 1849a [March], p. 158 [description only; no figures]; Philippi 1849­53, Syst. Conchyl. Cab., p. 37, pl. 5, f. 3 [plate published in 1849, text in 1852 ( Smith & England 1937)], see Fig. 1 M; Philippi 1849b, p. 457 [description only; no figures].

+ Natica texasiana var . Philippi, 1849; Philippi 1849­53, Syst. Conchyl. Cab., p. 80, pl. 12, f. 10. See Fig. 1 N.

+ Neverita duplicata ( Say, 1822) . Kabat et al. 1997, p. 19 [the four syntypes of Natica delessertiana Récluz in Chenu, 1843 at the MHNG].

Type localities:

Natica delessertiana Récluz in Chenu, 1843 – "La Louisiana, pré du Missisipi", USA ( Kabat et al. 1997: 19).

Natica fossata Gould, 1847 – „Florida Coast“, USA ( Gould 1847: 263).

Natica texasiana Philippi, 1849 – „Galveston“, Texas, USA ( Philippi 1849a: 159).

Natica texasiana var . Philippi, 1849 – „die Küste von Texas bei Galveston“, USA (Philippi 1849­53: 38).

Type material:

Natica delessertiana Récluz in Chenu, 1843 – 4 syntypes, 1300/48.1, and 1300/48.2, MHNG 1300/47.1, 1300/47.2 ( Figs. 1 B­D, H, E, and F, respectively).

Natica fossata Gould, 1847 – Unknown ( Johnson 1961).

Natica texasiana Philippi, 1849 – Unknown. Not at ZMB ( Kabat & Kilias 1991).

Natica texasiana var . Philippi, 1849 – Unknown. Not at ZMB ( Kabat & Kilias 1991).

Shell: Shell moderately small, more compact than Neverita duplicata ; proportionately higher (see Fig. 4 D); light to medium grey, apex dark, area below suture often decorated with reddish­brown band; aperture ovate, large, less oblique than in N. duplicata ; umbilical callus triangular, brownish, crossing umbilicus to connect to body whorl ( Figs. 4 D­F); umbilicus deep, centered by moderately small umbilical cord terminating in a funicle; deeply excavated, longitudinally striated umbilical canal anterior to umbilical cord, separated from wall of body whorl by distinct ridge or keel; umbilical channel often retains periostracum.

Distinctive characters to separate N. duplicata from N. delessertiana morphologically: ratio of height to width, shape of umbilical area; less consistently, shape of umbilical callus.

Figures

FIGURE 4: Typical shells of Neverita duplicata (A­C), and Neverita delessertiana (D­F). The umbilical areas are shown enlarged in C and F. The ridge (keel) within the umbilical channel (closed arrows in D and F) of N. delessertiana is present in all specimens investigated. Additionally, the shape of the umbilical callus often differs between the two species [open arrows in C and F]. The callus of N. delessertiana in most specimens is more triangular (F) while that of N. duplicata is more rounded (C).