Palaeozygopleura devonicans

Frýda, Jiří, Ferrová, Lenka & Frýdová, Barbora, 2013, Review of palaeozygopleurid gastropods (Palaeozygopleuridae, Gastropoda) from Devonian strata of the Perunica microplate (Bohemia), with a re-evaluation of their stratigraphic distribution, notes on their ontogeny, and descriptions of new taxa, Zootaxa 3669 (4), pp. 469-489 : 479

Palaeozygopleura devonicans (Barrande in Perner, 1903)

Lectotype. Unnumbered specimen figured by Perner (1907: pl. 60, figs 16–17), designated by Horný (1955: 34, pl. 1, fig. 1), NMP.

Paralectotypes. Two unnumbered specimens, NMP. One of those was figured by Perner (1907: 351, text-fig. 255), and by Horný (1955: pl. 1, fig. 2).

Type locality. Area between the villages of Mĕňany and Konĕprusy (49°54'25"– 49°55'01"N, 14°5'32"– 14°3'36.4"E), about 5 km SE of Císařský lom locality ( Fig. 1 ).

Type horizon. Vinařice Limestone (Praha Formation) or Suchomasty Limestone (Daleje-Třebotov Formation).

Remarks. Barrande in Perner (1907) described this species as Z. devonicans but had already figured and named it in Barrande in Perner (1903) (explanation of pl. 60, figs 15–17). Another specimen was figured by Perner (1907: text-fig. 255). However, none of Barrande in Perner´s (1903) syntypes agree exactly with his (1907) figures, maybe because of oversimplification of the figures. Nevertheless, all figured specimens come from the same syntype series and are conspecific. Horný (1955) selected the most complete shell from three of Perner´s syntypes as the lectotype of P. devonicans and figured it on plate 1, fig. 1.

Perner (1903) used the name Z. devonicans Barr. in an explanation of plate 60 for two specimens figured under numbers 15–17 and noted that they both came from Dlouhá hora hill. However, later, Perner (1907: 352) mentioned that Z. devonicans only occurs in reddish limestones with crinoids and listed Konĕprusy and Mĕňany as its localities without any comment about the previously noted Dlouhá hora locality. The latter locality is known as an area from which Barrande had described many Silurian species (see description of Kosov area in Kříž in Chlupáč et al. 1992), but no occurrence of reddish limestones with crinoids has been reported from there. On the other hand, reddish limestones with crinoids form two stratigraphically different horizons in the area between Konĕprusy and Mĕňany, specifically the Vinařice Limestone (Praha Formation) of Pragian age, and the Suchomasty Limestone (Daleje-Třebotov Formation) of upper Emsian age (Chlupáč et al. 1992). The Suchomasty Limestone only occurs in the Konĕprusy-Mĕňany area, and this lithostratigraphic unit was incorrectly considered to represent the stratigraphical equivalent of the Slivenec Limestone of the Praha Formation sixty years ago (Chlupáč 1955). This is why Horný (1955) mentioned the Slivenec Limestone as the type horizon for P. devonicans . As already noted by Horný (1955: 36), it is impossible to determine which one of those two different horizons provided P. devonicans .

According to Perner (1907), Barrande in unpublished manuscript used the name Turritella s. Zygopleura devonicans for the species described by Barrande in Perner as Z. devonicans , and the name Turritella devonicans for additional species described by Perner (1907: 352) as Z. alinae . The latter species comes from localities near Prague. Perner (1903, 1907, 1911) used a large fossil collection gathered earlier by Barrande and his collectors and had no direct information on their localities. Therefore, it is possible that this is the reason for the mistake he made in 1903 in the locality name.

Stratigraphic and geographic distributions. Palaeozygopleura devonicans has hitherto only known from six specimens (Horný 1955) coming from its type locality (area between the villages of Mĕňany and Konĕprusy). Its stratigraphic position is unclear (see above).

Figures

FIGURE 1. A. Generalized geological map of the Barrandian showing position of all known localities of palaeozygopleurid gastropods. Modified from Manda (2007). B. Generalized maps showing paleogeographic position of Perunica microplate during the Early Devonian. Modified from Torsvik (2009).