Ptereleotris tectus, Schwarzhans & Klots & Kovalchuk & Dubikovska & Ryabokon & Kovalenko, 2024

Ptereleotris tectus n. sp.

Figure 5 View FIGURE 5 D-J

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Holotype. NMNHU-P PI 2704 ( Figure 5 View FIGURE 5 D-F), Novyi Pliazh , western Ukraine, late Badenian.

Paratypes. 2 otoliths: NMNHU-P PI 2705 , 1 specimen, Staryi Zavod ; SMF PO 101.350 , 1 specimen, Staryi Zavod .

Additional material. 1 otolith, NMNHU-P 2706, Staryi Zavod.

Etymology. From tectus (Latin) = tectiform, roofshaped, referring to the shape of the dorsal rim resembling a roof.

Diagnosis. OL:OH = 0.78–0.88. Dorsal rim roofshaped with slightly protruding, similarly high positioned pre- and postdorsal projections. Inner face completely flat. Sulcus small, oval in shape, without subcaudal iugum.

Description. Small, moderately robust otoliths up to 0.9 mm in length (holotype). OL:OH = 0.78– 0.88; OH:OT = 3.0. The dorsal rim is high but relatively little bent, highest at its middle and with slightly protruding pre- and postdorsal projections. Anterior and posterior rims are vertical with broad, shallow concavities below pre- and postdorsal projections giving the dorsal rim the characteristic roof shape. The ventral rim is slightly bent, horizontal. All rims are sharp and smooth. The inner face is completely flat with a centrally positioned, small, deepened, oval, unstructured sulcus without the subcaudal iugum. OL:SuL = 2.0–2.3; sulcus inclination angle 13–16°. Dorsal depression is wide, with indistinct margins; the ventral furrow is relatively distinct leading up to the level of the sulcus. The outer face is distinctly convex and smooth.

Discussion. Microdesmid otoliths are small and rare in the fossil record: Microdesmus paratethycus Schwarzhans, 2017 from the late Badenian of Bulgaria and Paroxymetopon alienus Bratishko and Schwarzhans, 2023 from the Bessarabian of Ukraine. For comparison with extant otoliths of Ptereleotris , reference is made to Bratishko et al. (2023).