Ephydatia cf. facunda Weltner, 1895

Pronzato, Roberto, Pisera, Andrzej & Manconi, Renata, 2017, Fossil freshwater sponges: Taxonomy, geographic distribution, and critical review, Acta Palaeontologica Polonica 62 (3), pp. 467-495 : 484

Ephydatia cf. facunda Weltner, 1895

Fig. 18.

Horizon: Lutetian, middle Eocene.

Locality: Giraffe Kimberlite maar, Northern Canada (64°44’ N, 109°45’ W) .

References: Pisera et al. 2016.

Description (emended from Pisera et al. 2016).—Only disassociated spicules. Possible megascleres large oxeas (162.3– 307 × 8.7–12.8 μm, usually 220–250 × 9–10 μm), straight to slightly curved, microspinose, with scattered small spines or tubercles, and the tips tapering to a sharp point. Some centrotylote forms present. Gemmuloscleres birotules with incised margins of both rotules and spiny shaft; spines (4–20, usually 6–12) scattered, large (extending in length to the rotule margin) and smooth with acute tips; rotules moderately smooth to strongly incised; at their center often rises a small rounded process (umbonate rotule).

Gemmuloscleres size highly variable (26–57 μm in length, mean 41.5 μm; shaft (not including spines) 5–11 μm in thickness mean 7.2 μm; rotulae diameter 15–28 μm mean 21.4 μm. Aberrant gemmuloscleres also present.

Remarks.—This species was recently very well described but for the sake of completeness this description is repeated here. Gemmuloscleres of E. cf. facunda are virtually identical, including their variability as in the extant species E. facunda , due to large time gap separating both forms, it was described as E. cf. facunda .