dc:description"Figs 1a–n. Arcuospathidium bromelicola from life (a–d, j–l) and after protargol impregnation (e–i, m, n). a – left side view of a representative specimen, length 85 µm; b – surface view, showing the minute (≤ 1 µm) cortical granules arranged in oblique rows; c – the oral bulge is distinctly curved in 70% of specimens; d – frontal view of a straight oral bulge studded with extrusomes; e, f – ciliary pattern of left and right side and macronucleus of holotype specimen, length 85 µm; note the Arcuospathidium ciliary pattern on the left side (e), i.e., the ciliary rows do not curve ventrally anteriorly; g–i – shape variability of oral bulge, respectively, circumoral kinety; j – mature extrusomes are rodshaped and about 4 µm long; k, l – overview and detail of resting cyst in optical section. Note the conspicuous, pillar-shaped lepidosomes most frayed anteriorly; m, n – length comparison of trophont and theront. BU – oral bulge, B(1–3) – dorsal brush (rows), CK – circumoral kinety, CV – contractile vacuole, E – extrusomes, EL – external layer, EP – excretory pore, FV – food vacuoles, G – cortical granulation, IL – internal layer, L – lipid droplet, MA – macronucleus, MI – micronucleus, SL – slime layer, T – anterior tail of dorsal brush rows. Scale bars: 2.5 µm (l), 15 µm (h, k), 20 µm (g, i), and 40 µm (a, e, f, m, n).";
dc:description"Figs 2a–m. Arcuospathidium bromelicola from life. a, b – left side and ventral view, showing body outline of a specimen with strongly convex oral bulge (arrowheads); c – oral bulge extrusomes (some marked by arrowheads) are rod shaped and about 4 × 0.3 µm in size; d – a pillar of a squashed cyst; e – bright field micrograph of a resting cyst in optical section, showing the thin external layer (arrow) and thick internal layer (opposed arrowheads); f–h – optical section of cyst pillars, showing the variability of the distal end; i, j – optical section and surface view, showing the narrowly spaced pillars; k – arrowheads mark overturned pillars in a squashed cyst; l, m – optical sections, showing the cysts filled with lipid droplets and surrounded by a narrow slime layer. CV – contractile vacuole, L – lipid droplets, MA – mac- ronucleus, SL – slime layer. Scale bars: 2.5 µm (f–h), 10 µm (c), 15 µm (e, i, j, l, m), and 40 µm (a, b).";
dc:description"Figs 3a–k. Arcuospathidium bromelicola after protargol impregnation. a, b – left and right side view of a representative specimen; c, d – ventral and dorsal view of anterior body region, showing the cuneate, slightly curved circumoral kinety and the dorsal brush; e – left side view, showing the heterostichad dorsal brush with end of row 3 marked by an arrowhead; f – a horseshoe-shaped macronucleus accompanied by an ellipsoidal micronucleus with a minute, hemispherical cap; g–i – specimens with distinctly curved oral bulge, respectively, circumoral kinety;j – post-conjugant with two macronuclear nodules; k – a trophont with two large food vacuoles which contain ciliates and dislocate the macronucleus. BU – oral bulge, B(1–3) – dorsal brush (rows), CK – circumoral kinety, E – extrusomes, MA – macronucleus, MI – micronucleus. Scale bars: 10 µm (e, f), 15 µm (c, d, g, h), 30 µm (k), and 40 µm (a, b, i, j).";
