Ericiolus multistellatus (H.A. Thomsen & J.B. Østergaard) Archontikis & Jer.R. Young 2023

Archontikis, Odysseas A., Millán, Josué G., Winter, Amos & Young, Jeremy R., 2023, Taxonomic re-evaluation of Ericiolus and Mercedesia (Prymnesiophyceae) and description of three new species, Phycologia 62 (2), pp. 179-193 : 188

Ericiolus multistellatus (H.A. Thomsen & J.B. Østergaard) Archontikis & Jer.R. Young comb. nov.

Figs 35, 36

BASIONYM: Mercedesia multistellata H.A. Thomsen & J.B. Østergaard in Thomsen & Østergaard 2015, Acta Protozoologica 54, p. 159, figs 9, 10, 14, 15.

REMARKS: Thomsen & Østergaard (2015) note that “a cluster of nannoliths reminiscent of M. multistellata have been observed from tropical waters (Phuket, Thailand)”. We have found another three such clusters (two of them shown in Figs 35, 36 ) from the LPZ of the subtropical South Atlantic Ocean and Sargasso Sea. This seems to confirm that the species occurs both in the surface waters of the Arctic and the LPZ of the sub-tropics. This pattern is also shown by other living coccolithophores, such as Algirosphaera robusta (Lohmann) R.E. Norris and Calciopappus caudatus Gaarder & Ramsfjell.

Figures

Figs 30–36. SEM micrographs of Ericiolus cf. bendifii, E. aspiphorus comb. nov. and E. multistellatus comb. nov. Scale bars = 1 μm. Fig. 30. Ericiolus cf. bendifii. Dense layer of star-shaped nannoliths showing bifucation near their centre and a short central process on distal side. Fig. 31. Ericiolus cf. bendifii. Detailed view of specimen in Fig. 30, with two nannoliths in, respectively, distal (upper nannolith) and proximal (lower nannolith) views. Fig. 32. Ericiolus cf. bendifii. Collapsed and dense layer of triradiate nannoliths bearing a short central spine at the centre; the spine is usually seen collapsed. Fig. 33. Ericiolus cf. bendifii. Detailed view of nannoliths from Fig. 32; arrow indicates the upturned end of the ray tips of the nannolith. Fig. 34. Collapsed nannoliths of Ericiolus aspiphorus comb. nov.. Arrow indicates the short central knob observed at the nannolith centre in distal view. Fig. 35. Collapsed dense layer of E. multistellatus comb. nov., triradiate nannoliths. Fig. 36. Well-preserved triradiate nannoliths of E. multistellatus comb. nov., which bear a small knob (arrow) at their centre, in distal view. Bottom left side showing a Solisphaera turbinella A. Kahn & M-P. Aubry coccolith.