Cubiculum inornatus Xing et al., 2015

Hedeny, Magdy El, Mohesn, Sara, Tantawy, Abdel-aziz, El-Sabbagh, Ahmed, AbdelGawad, Mohamed & El-Kheir, Gebely Abu, 2023, Bioerosion traces on the Campanian turtle remains: New data from the lagoonal deposits of the Quseir Formation, Kharga Oasis, Egypt, Palaeontologia Electronica (a 40) 26 (3), pp. 1-21 : 7-8

Cubiculum inornatus Xing et al., 2015

( Figure 3D, F )

Material. Four ellipsoidal chambers on a carapace remain (NVP006).

Description. Discrete, ellipsoidal borings in bone with marked concavity of flanks and bottom and marked constriction of walls in the upper area. Boring boundaries, wall and bottom are sharp and smooth. No bioglyphs or fillings were observed.

Discussion. In the present assemblage, C. inornatus is associated with other trace fossils; C. ornatus and Osteocallis mandibulus . Cubiculum inornatus resembles C. ornatus but is differentiated by having tapering ends and the absence of bioglyphs in their walls. Cubiculum levis Pirrone et al. (2014, p. 253 , figure 3) differs from our specimens in having interior bowl-shaped morphology and a marked constriction of walls in the upper area.

Producer. Indeterminate osteophagous insect (Xing et al., 2015; Paes Neto et al., 2016).

Stratigraphic and geographic distribution. Campanian of the Qarn Ganah, Kharga Oasis (this study). Cubiculum inornatus was recorded from the Middle Triassic of Brazil ( Paes Neto et al., 2016) to Lower‒Middle Jurassic of China and South Africa (Xing et al., 2015). The present determination greatly expands the stratigraphic range of C. inornatus to the Upper Cretaceous (Campanian).

Figures

FIGURE 3. (A) Nihilichnus nihilicus, circular, subcircular to ellipsoidal non-penetrating holes (arrows) on the carapace peripheral. (B, C) Karethraichnus lakkos. (B) Cluster of bowl-shaped pits (arrows) of on the carapace peripheral. (C) Small rounded holes (arrows) of which are not completely penetrating the plastron fragments. (D) External surface of carapace peripheral containing three ichnospecies Cubiculum ornatus, C. inornatus and Osteocallis mandibulus (E, F, and H, respectively). (E) Cubiculum ornatus (arrows), showing the characteristic features of the ichnospecies with well pronounced bioglyphs. (F) Cubiculum inornatus (arrow), showing details of the morphological features the ichnospecies. (G) Cubiculum isp., showing borings arranged in groups of mostly parallel to each other and infilled with sediments. (H) Osteocallis mandibulus (ellipse), showing, randomly oriented surface borings with distinct arcuate (commonly paired) scratches in turtle skeleton. Scale bars equal 0.5 cm, except for B, D and G, which are 1.0 cm, and for C, which is 0.4 cm.