Joania peyrerensis, Bitner & Lozouet & Cahuzac, 2013

Bitner, Maria Aleksandra, Lozouet, Pierre & Cahuzac, Bruno, 2013, Upper Oligocene (Chattian) brachiopod fauna from the Aquitaine Basin, southwestern France and its paleoenvironmental implications, Geodiversitas 35 (3), pp. 579-606 : 592-594

publication ID	https://doi.org/ 10.5252/g2013n3a418
persistent identifier	https://treatment.plazi.org/id/03BD87E7-575A-0908-FF0B-FB2BF512FA2D
treatment provided by	Marcus
scientific name	Joania peyrerensis
status	sp. nov.

Treatment

Joania peyrerensis n. sp.

( Fig. 7 View FIG A-I; Table 7)

TYPE MATERIAL. — Holotype MNHN.F.A46532: specimen figured in Fig. 7 View FIG A-C; paratypes MNHN.F. A46533 View Materials , A46534: specimens figured in Fig. 7 View FIG D-I.

ETYMOLOGY. — Referring to the name of type locality, Peyrère.

MATERIAL EXAMINED. — Peyrère: one complete specimen. — Bélus: three complete specimens and one dorsal valve.

TYPE HORIZON AND LOCALITY. — Upper Oligocene, Peyrère, Aquitaine Basin, SW France.

DIAGNOSIS. — Small, rounded subrectangular Joania with surface ornamented by six to eight distinct ribs; teeth triangular; dorsal septum high, triangular in profile with serrations; tubercles on inner margin of both valves. DESCRIPTION

Shell small, not exceeding 3 mm in length, rounded subrectangular in outline with maximum width at mid-valve, weakly biconvex. Shell surface covered with 6 to 8 distinct ribs. Hinge line shorter than maximum width, slightly curved. Anterior commissure rectimarginate. Beak high with distinct beak ridges. Interarea narrow. Foramen large, triangular, hypothyrid flanked by elevated, narrow deltidial plates.

Ventral valve interior with plate-like, triangular teeth ( Fig. 7 View FIG F-H). Pedicle collar wide, excavate anteriorly, supported by a slender septum that extends beyond mid-valve. On inner surface radial ridges terminating in tubercles ( Fig. 7I View FIG ).

Dorsal valve interior with narrow but high inner socket ridges. Dental sockets deep. Cardinal process distinct. Septum high, triangular in profile, with 4 serrations. Numerous tubercles on inner margin ( Fig. 7D, E View FIG ). Loop not preserved.

REMARKS Álvarez et al. (2008) created Joania as a monospecific genus, however, since that time several Argyrotheca species have been transferred into the genus Joania , based mostly on the important diagnostic character – numerous radial ridges terminating anteriorly in tubercles on the inner margin. ffle presence of marginal tubercles in the specimens from the Aquitaine Basin supports their attribution to the genus Joania .

In the ornamentation of 6-8 distinct, sharp ribs J. peyrerensis n. sp. can be easily distinguished from other so far described Joania species. ffle shell surface of J. cordata is smooth or covered with almost imperceptible costae ( Logan 1979; Bitner 1990; Álvarez et al. 2008). In addition, both species differ in the nature of the teeth; in J. peyrerensis n. sp. the teeth form a triangular plate, while in J. cordata they are hooked.

ffle shell of a Recent Indo-Pacific species J.arguta (Grant, 1983) is also completely smooth without any costae (Bitner 2008; Simon 2010). ffle teeth in this species are, similarly like in J. cordata , hooked given off dorsally, thus differing clearly from J. peyrerensis n. sp.

ffle studied specimens differ strongly from the Lower Pleistocene species from southern Italy, Joania ageriana , originally described as Argyrotheca ageriana by Taddei Ruggiero (1993). Joania ageriana is much larger, reaching 7 mm in length, and ornamented by 14 to 18 rounded ribs ( Taddei Ruggiero 1993, 1994)

Dulai (2010a) attributed a single dorsal valve from the Late Miocene of Italy to Joania aff. falunica (de Morgan, 1915), recognizing in this brachiopod diagnostic characters of the genus. ffle poor material prevents any formal description of a new species.