Lepidochitona chalossensis, Dell'Angelo, Lesport, Cluzaud & Sosso, 2020

Dell’Angelo, Bruno, Sosso, Maurizio & Taviani, Marco, 2025, The Cenozoic European Polyplacophora (Mollusca), Zootaxa 5704 (1), pp. 1-377 : 222-223

publication ID	https://doi.org/10.11646/zootaxa.5704.1.1
publication LSID	lsid:zoobank.org:pub:747DFE8B-156A-493A-8817-5F861C4D6319
persistent identifier	https://treatment.plazi.org/id/03FEF726-FF32-4ECE-0FAD-FBF06B599661
treatment provided by	Plazi
scientific name	Lepidochitona chalossensis
status

Treatment

Lepidochitona chalossensis View in CoL Dell’Angelo, Lesport, Cluzaud & Sosso, 2020

Fig. 110 View FIGURE 110

Lepidochitona chalossensis View in CoL Dell’Angelo, Lesport, Cluzaud & Sosso, 2020b, p. 26, fig. 17.

Type material. Holotype: MHNBx 2020.2.7, intermediate valve, width 2.2 mm ( Figs 110A–D View FIGURE 110 ). Paratype: MHNBx 2014.14.22, Benoist collection, labeled Tonicia gaasensis de Rochebrune, 1882 , intermediate valve, width 2.8 mm.

Type locality. Gaas ( France) .

Type stage. Oligocene (Rupelian).

Material examined. Oligocene (Rupelian): Gaas: type material plus Rupelian levels: 1 intermediate valve ( BD 935 ); Espibos: 1 intermediate valve ( DA); Larrat: 59 intermediate valves ( AC, DA, JCV). Maximum width: 3.3 mm .

Description. Head and tail valves not present. Intermediate valve broadly rectangular (W/L = 1.57–1.82), carinate in anterior profile, highly elevated (H/W = 0.43–0.58), anterior margin convex, lateral margins rounded, posterior margin concave at both sides of very prominent apex, lateral areas scarcely differentiated.

Tegmentum entirely covered by irregularly arranged, elevated, roundish granules, some coalescent, diameter up to 93 μm; each granule bearing a subcentral megalaesthete, and up to six micraesthetes arranged irregularly along margin, additional micraesthetes randomly placed between granules.

Articulamentum with apophyses small, triangular, slit formula one slit for each side.

Remarks. Lepidochitona chalossensis Dell’Angelo, Lesport, Cluzaud & Sosso, 2020 is characterized by the tegmentum entirely covered by irregularly arranged roundish granules, a carinate anterior profile of the intermediate valves, and very prominent apex.

The valve from the Benoist collection at MHNBx (MHNBx 2014.14.22, see Dell’Angelo et al. 2020b), labeled Tonicia gaasensis de Rochebrune, 1882 , has been considered conspecific to Lepidochitona chalossensis by Dell’Angelo et al. (2020b).

Comparisons. The closest species is Lepidochitona larratensis Dell’Angelo, Lesport, Cluzaud & Sosso, 2020, from which L. chalossensis differs by the different shape of the intermediate valves (H/W = 0.43–0.58 vs. 0.56–0.62 in L. larratensis ), the carinate anterior profile (vs. semicarinate in L. larratensis ), and the convex anterior margin (vs. slightly sinuose in L. larratensis ).

Distribution. Middle Oligocene: northeastern Atlantic (Rupelian): Aquitaine Basin, France: Gaas ( Dell’Angelo et al. 2020b).