Succinea omanensis, Neubert & Damme, 2012

Neubert, Eike & Damme, Dirk van, 2012, Palaeogene continental molluscs of Oman, Contributions to Natural History 20, pp. 1-28 : 12-13

Succinea omanensis sp. nov.

( Figs. 11–12 )

Type specimens: Holotype NMBE 5018975 ; paratypes NMBE 5018976 , 5019044 ; paratypes Thaytiniti NMBE 5019045–5019047 .

Type locality: Wadi Darbat , Dhofar, Oman .

Stratum typicum: Paludal biomicritic limestones of the Zalumah Formation.

Age: Late Priabonian.

Material: Only known from the type locality.

Diagnosis: A small shelled member of Succinea , with a rapidly growing teleoconch and the last whorl exceeding half of the complete height of the shell.

Etymology: omanensis refers to the provenance of this new species.

Description: Small shells with a rapidly growing teleoconch, shells probably reach a total shell length of about 10 mm; preserved paratype shell with almost 4 whorls, protoconch eroded; suture shallow, well-marked and somewhat reinforced, subsuturally slightly crenulate; teleoconch covered by a regular pattern of fine, axial growth riblets; last whorl amply open, constituting more than half of the complete height of the shell.

Measurements: Holotype ( Fig. 11 ): H = 4.94 mm; Wh <3; paratype ( Fig. 12 ): H = 7.67 mm; Wh> 3.5.

Remarks: It has to be stressed that the affiliation of this species to the extant genus Succinea is debatable. However, the shells are in fact quite similar to a number of Modern species within Succinea and related genera, which today are defined by using anatomical and molecular data, inapplicable to fossils. Creating a fossil genus to harbour these shells seems not to be advisable as long as material is so meagre and good arguments in favour of such a genus are available. Today, there are only two records of an extant succineid species from the Arabian Peninsula, i.e. Quickia concisa (MORELET, 1848) . The shell of this species is smaller, and it has a deep and simple suture, and thus cannot be identified with the fossil specimens from Wadi Darbat ( Neubert 1998: 370, fig. 63).

Figures

Figs. 11–12: Succinea omanensis sp. nov. Fig. 11: Wadi Darbat, holotype NMBE 5018975 in frontal and ventral view. Fig. 12: Paratype NMBE 5018976, same locality.