Anteclevelandella constricta ( Kidder, 1937 )

Kotyk, Michael, Bourland, William A., Soviš, Matyáš, Méndez-Sánchez, Daniel, Škaloud, Pavel, Varadínová, Zuzana Kotyková & Čepička, Ivan, 2024, Morphology maưers: congruence of morphology and phylogeny in the integrative taxonomy of Clevelandellidae (Ciliophora: Armophorea) with description of six new species, Zoological Journal of the Linnean Society 202 (1), pp. 1-51 : 19

Anteclevelandella constricta ( Kidder, 1937)

( Figs 19 , 20 ; Supporting Information, Tables S15–S21) Six populations (ASS, PAA, PRG, SRU, STH #1, and STH #2) were morphologically characterized by both in vivo observations and protargol preparations, and one population (PAC) was characterized in vivo only. When present, the ciliate was usually abundant.

Description based on the above populations: Medium- to large-sized Clevelandellidae (on average 128 × 38 µm in vivo, range 78–192 × 21–67 µm; on average 117 × 33 µm in protargol preparations, range 94–142 × 20–47 µm). Shape elongated, cylindrical, transverse constriction at level of macronucleus, anterior cell end broadly tapered, posterior end transversely truncate with short peristomial overture, peristomial projection indistinct since gradually merges with body proper. Macronucleus broadly ellipsoidal, long axis oriented transversely, karyophore at right and left ends of macronucleus. Aggregation of cytoplasmic platelets between macronucleus and anterior end of cell (possibly amylopectin).

Somatic cilia limited to approximately anterior 44% of cell length. About 15 ciliated free transverse kinetofragments, comprising five basal bodies each, occupy right suture in anterior half of cell ( Fig. 18D ). Circumperistomial kineties only sparsely ciliated.

Oral ciliature as for the family. Adoral zone extends about 48% of cell length, composed of about 47 membranelles on average (range 36–56).

Remarks: Regarding measured characteristics (Supporting Information, Tables S15–S21), our populations are slightly larger than Kidder’s (1937) isolates, very closely match those of Albaret (1975), and are similar to measurements published by Yamasaki (1939) and Pecina and Vďačný (2020b). Individual populations are very similar except for the number of adoral membranelles, which ranges from mean 39 (PAA) to mean 52 (STH population 1). Pecina and Vďačný (2020b) found similar variability in adoral membranelle number in their Thai population. The only visible shape variation can be seen in STH population 2, which lacks the typical constriction and has a slender, more acutely pointed anterior end, differing somewhat from the typical phenotype ( Fig. 19C ).

Figures

Figure 18. Clevelandella fryntai sp.nov.in the scanning electron microscope.From SRU. (A, B) slender morphotype, (C–F) broad morphotype. A, dorsal view showing cytoproct on left protuberance (black arrowhead), anterior margin of peristomial overture (white arrowhead), circumperistomial kineties (white arrow), cilia of adoral membranelles (black arrow), and metachronal ciliary waves (asterisk). B, dorsal view showing the left protuberance (black arrowhead), metachronal ciliary waves (asterisk), the anterior margin of the peristomial overture (white arrowhead), and cilia of the circumperistomial kineties (black arrow).C, ventral view of showing characteristic lateral twisting of left protuberance also seen in vivo (black arrowhead, compare Fig.17E), the cytoproct (white arrowhead) and cilia of the adoral membranelles (black arrow). D, dorsal view showing straight course of the dorsal somatic kineties (white arrowhead), the left protuberance (white asterisk), cilia of the circumperistomial kineties (black arrowhead), and cilia of the adoral membranelles (black arrow). E, ventral view showing left-hand spiralling ventral somatic kineties (white asterisk). F, dorsal view showing straight dorsal somatic kineties (white arrowhead), cilia of circumperistomial kineties (black arrowhead), and area of somatic cilia matted during preparation (black asterisk). Scale bars:20 µm.

Figure 19.Anteclevelandella constricta in vivo (A–C) and after protargol impregnation (D–G). From PAA (A), STH population 1 (B) from STH population 2 (C), from ASS (D), from STH population 1 (E), and from SRU (F, G). A, left lateral view (optical section) showing two large contractile vacuole collecting vesicles (white arrowheads), adoral membranelles (black arrow) and left part of the karyophore (black arrowhead). B, ventral; view (optical section) showing contractile vacuole on the small left protuberance (white arrowhead). C, ventral view (optical section) showing shape variation with more narrowly tapered anterior end (white arrowheads), the micronucleus (white arrow), and the margin of the peristomial overture (black arrowhead). D, right lateral view showing kinetofragments in suture between ventral (white asterisk) and dorsal (black asterisk) somatic kineties, micronucleus (white arrowhead), paroral membrane (black arrow), and looping kineties on the peristomial projection (white arrow). E, ventral view (optical section) showing the transverse orientation of the macronucleus with right and left parts of the karyophore (black arrows) ans slightly pronounced left lobe (white arrow). F, ventral view showing position of the cytostome (white asterisk), paroral membrane (white arrowhead), and adoral membranelles (black arrowhead). G [same cell as (F)], detail view of the long (white arrowhead) and short (black arrowhead) files of the paroral membrane.Ma, macronucleus.Scale bars: 20 µm (A–F), 10 µm (G).

Figure 20. Anteclevelandella constricta in the scanning electron microscope. From PAA. A, ventral view showing cilia of the adoral membranelles protruding from the peristomial overture (white arrowhead), the unciliated posterior body part (black asterisk), and cilia protruding from cytoproct on the left lateral protuberance (black arrowhead). B, dorsal view showing the right kinetal suture (black arrowhead) between the dorsal kineties (black asterisk) and ventral kineties (white asterisk) right suture, and sutural kinetofragments (black arrow). C, left ventrolateral view showing position of cytoproct on left posterior protuberance (black arrowhead) and the anterior margin of the peristomial overture (black arrow). D, left lateral view showing the location of the cytoproct (white arrowhead), short left kinetal suture (white arrow), and adoral membranells (black arrowhead). E, detail of same cell as (B) showing short transverse kinetofragments in anterior part of right suture (white arrows) between dorsal (black asterisk) and ventral (white asterisk) kineties. F, showing the leftward-spiralling ventral kineties which lack normal cilia (white arrows) and a cilium protruding from the cytoproct (black arrow). Scale bars: 20 µm (A–D), 5 µm (E–G).