Clevelandella fryntai, 2024

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 : 12-16

Clevelandella fryntai sp.nov.

( Figs 16–18 ; Supporting Information, Tables S13, S14)

Description based on populations from SRU hosts from Cambodia: Spade-shaped Clevelandella , size in vivo quite variable 113– 189 × 55–79 µm, usually about 143 × 63 µm; size in protargol preparations 110–167 × 51–82 µm, usually about 130 × 65 µm; dorsoventrally flattened, widest in posterior half of cell, anterior end broadly tapered, cell shape varies depending on host and possibly nutritional status, i.e. morphology less variable within than between hosts, well-fed cells plump (L/W ratio about 2.6), less well-fed cells narrower (L/W ratio about 2.1), cells of intermediate length–width ratio common (range 1.6–2.8). Peristomial projection length relative to cell length quite variable depending on nutritional status (average in all cells about 19%; about 25% in more slender, less well-fed cells; about 17% in plumper, well-fed cells), peristomial overture extends nearly entire length of peristomial projection regardless of nutritional state ( Fig. 18A–D ). Macronucleus in anterior half of cell, inverted teardrop-shaped ( Fig. 17G ) to lenticular ( Fig. 17B , H), chromatin granular; micronucleus distinctly ellipsoidal ( Fig. 17H ), adjacent to macronucleus, about 7 × 4 µm. Presence of karyophore highly variable, not seen or quite inconspicuous in vivo, when present, appearance in protargol preparations ( Fig. 17G ) highly variable (seen at anterior and posterior ends of macronucleus in 11 of 39 cells, anterior end only in 7 of 39 cells, at posterior end only 4 of 39 cells, undetectable in 17 of 39 cells). Swims lazily. Somatic ciliature composed of about 80–100 somatic ciliary rows in Clevelandellidae pattern, about 20–25 ciliary rows extend on to peristomial projection, somatic cilia restricted to approximately anterior two-thirds of cell except for four or five ciliated circumperistomial kineties. Sutural kinetofragments absent. Adoral zone usually extends about 45% of body length, composed of an average of 60 membranelles, base of membranelles longest in posterior one-third of adoral zone. POM as described for the family.

Remarks on phenotypic variability: Two genetically different populations were detected in SRU host: (i) ( Fig. 17A ) and (ii) ( Figs 17B–K , 18). Cells of population (i) were markedly larger than cells of population (ii)—cell size in vivo 180 × 65 µm vs. 141 × 64 µm (Supporting Information, Tables S13, S14).

Based on overall morphology, the cells can be divided into two more or less distinct morphotypes: slender ( Figs 16A , 17A, B, G, 18A, B) and broad ( Figs 16B–E , 17C–E, H–K, 18C–F). In population (i) only the slender morphotype was detected.

Occurrence: Clevelandella fryntai occurred in all six dissected SRU individuals (all from the same family group). Population (i) was detected in only one individual (subadult female), the very same in which C. sidi (see above) was found. The five remaining hosts harboured population (ii): in four (male, two females, and a larva) of them the slender and broad morphotypes co-occurred and in one (larva) only the slender was present.

Redescriptions of known species of Clevelandellidae

In addition to the newly described species, a number of known species was observed, namely: Anteclevelandella constricta , R. nipponensis , R. hastula , Paraclevelandia brevis , Paraclevelandia simplex , C. elongata , C. parapanesthiae , C. kidderi (weconsider C.lynni Pecina and Vďačný, 2020 as a junior synonym of C. kidderi , see discussion), and C. panesthiae . Most, but not all available ciliate populations were morphologically characterized. For known species, except C. elongata , which has not been reported since its original discovery by Kidder (1937), descriptions are limited to those characters not previously reported, previously recorded inaccurately (e.g. somatic ciliature), or deviating significantly from previous descriptions. Apart from them, two species were detected but left undescribed, namely: Rhynchoclevelandella sp. 2 and Clevelandella sp. 4 . The hosts infected and the occurrence of individual species are summarized inSupporting Information, Table S48.

Figures

Figure 16. Schematic drawings of Clevelandella fryntai sp. nov.from life (A, B) and after protargol impregnation (C–E). From SRU.A, ventral view. B, ventral view.C, ventral view.D, ventral infraciliature.E, dorsal infraciliature.AP, cytoplasmic granules, possibly amylopectin; AZM, adoral zone of membranelles; CPK, cilia of circumperistomial kineties; CV, contractile vacuole; CW, ciliary whorl of left protuberance; K, karyophore; Ma, macronucleus, Mi, micronucleus; POM, paroral membrane; POV, peristomial overture; SK, somatic kineties.Scale bars:20 µm.

Figure 17.Clevelandella fryntai sp.nov.from life (A–E) and after protargol impregnation (F–K).From SRU.(A, B, F, G, K) slender morphotype, (C–E, H–J) broad morphotype.A, ventral view showing posterior extent of ciliation on the right margin (white arrowhead) and left margin (black arrowhead).B, dorsal view showing contractile vacuole (white arrowhead) and straight dorsal kineties (white arrow).C, ventral view (optical section) showing cytoplasmic granules, possibly amylopectin (black arrow), right kinetal suture (white arrowhead), adoral membranelles (black arrowhead),and cytoproct (white arrow).D, ventral view showing left-hand spiralling kineties (white arrowhead) and cilia of adoral membranelles (white arrow).E, ventral view showing the margin of the peristomial overture (black arrowhead) and bulbous left protuberance extending over left cell margin (white arrowhead).F, detail showing karyophore(black arrowhead).G, ventral view (optical section) showing the karyophore (black arrowhead), micronucleus (white arrow), and cytoproct (white arrowhead).H, dorsal view showing karyophore (black arrowheads), micronucleus (white arrowhead), and adoral membranelles (black arrow).I, ventral infraciliature showing left-hand spiralling kineties (asterisk) and looping kineties of the peristomial projection (white arrow). J, dorsal infraciliature showing straight dorsal kineties (asterisk). K, detail view showing diplostichomonad paroral (black arrow).Ma, macronucleus.Scale bars: 20 µm (A–E, G–J), 10 µm (F, K).

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.