Crisia aculeata Hassall, 1841

Moissette, Pierre, Antonarakou, Assimina, Kontakiotis, George, Cornée, Jean-Jacques & Karakitsios, Vasileios, 2021, Bryozoan faunas at the Tortonian-Messinian transition. A palaeoenvironmental case study from Crete Island, eastern Mediterranean, Geodiversitas 43 (26), pp. 1365-1400 : 1380

Crisia aculeata Hassall, 1841

( Fig. 8 A-C)

Crisia aculeata Hassall, 1841: 170 , pl. 7, figs 3-4. — Harmer 1891: 132, pl. 12, fig. 4. — Hayward & Ryland 1985: 50, fig. 14. — Harmelin1990: 1602, figs 2, 3-6.

OCCURRENCE. — Recent: Eastern Atlantic (50-60 m in the North Sea, much deeper in Norway, the Bay of Biscay and Morocco: 135- 1000 m) and Mediterranean (115-480 m).

DESCRIPTION

Cellariiform colony. Internodes short (8-12 zooids). The first ramification arises from the third zooid. Pseudopores elongate and relatively rare. Gonozooid pyriform with a discrete ooeciostome situated near the base of the following zooid.

REMARKS

This species is poorly known and has rarely been illustrated. It has often been considered as a variety of C. eburnea (Linnaeus) to which it resembles. Harmelin (1990) distinguished a northern (Atlantic) and a southern form (Atlantic coast of Morocco, Mediterranean). The main differences are a higher number of zooids (9-12) per internode and a mitre-shaped gonozooid in the southern form.

Figures

FIG. 8. — A-C, Crisia aculeata Hassall, 1841; A, internode, frontal view, POTB13: AMPG(IV) 2828a; B, internode, dorsal view, POTB13 2828b: AMPG(IV); C, internode with gonozooid, KAP22: AMPG(IV) 3339. D-F, Crisia denticulata (Lamarck, 1816); D, internode, frontal view, POTB13:AMPG(IV) 2829a; E, internode dorsal view, POTB13: AMPG(IV) 2829b; F, gonozooid, POTB13: AMPG(IV) 2829c. Scale bars: A, 500 µm; B-F, 200 µm.