Laboea strobila

Body conical, 85 (45-115) µm long and 42 (20-55) µm wide; screw-like appearance (Fig 1,2,4,5,6,7,11,12); short trichites as extrusomes, inserted anterior to the girdle kinety (Fig 1,8); distended cell surface between whorls (Fig 1,4,9,11). Shallow acentric oral cavity; peristomial collar small (5 µm high); 14 (10-19) APks and 16 (12-24) VPks, APZ and VPZ separated (Fig 1,2,8,9); paroral kinety (PO) ciliated, extending deeply into oral groove. Girdle kinety as sinistral helix of approximately 5 whorls when viewed from posterior (Fig 1,6,8,9) ? kinetids with stubby cilia; ventral kinety short, 3-15 dikinetids from the posterior end of the girdle to the aboral pole, not seen in Lugol?s. Multiple macronuclei (25-75), spheroid, scattered throughout the cytoplasm (Fig 1,6,8,9).

Temperature: 5-19 ºC; eurythermal Salinity: 7-32 ?; euryhaline

Cell conical; screw-like appearance, girdle kinety as helix of approximately 5 whorls; multiple macronuclei, spheroid, scattered throughout cytoplasm.

Mixotrophic, chloroplast-retention, nanoflagellates, centric diatoms (5-10 µm)

Swims in a zigzag pattern with sharp turns

Lohmann (1908) described Laboea strobila as the type species of the genus. Wulff (1919) synonymised Laboea with Strombidium since species of both genera possess cortical polysaccharide plates. Fauré-Fremiet (1924) emended the diagnosis of the genus Laboea to include the typical spiraled shape. Montagnes et al. (1988) redescribed the species after protargol impregnation and added the series of whorls formed by the sinistrally spiralling girdle and the short ventral kinety as diagnostic characters for the genus Laboea.