Apoamphisiella tihanyiensis

Paiva, Thiago Da Silva & Neto, Inácio Domingos Da Silva -, 2004, Comparative morphometric study of three species of Apoam­ phisiella Foissner, 1997 (Ciliophora: Hypotrichea) from Brazilian locations, including a description of Apoamphisiella foissneri sp. n., Zootaxa 505, pp. 1-26 : 16-20

Characterization of Apoamphisiella tihanyiensis population from Cabiúnas Lagoon. ( Figs. 10–13 , 29 – 32; Table 1)

Occurrence

Apoamphisiella tihanyiensis specimens were found in samples collected from Cabiúnas Lagoon, in the same location where A. jurubatiba was discovered. The neotype population, characterized by Foissner (1997) , was obtained from samples of soil from the Amazonian rain forest near the town of Iquitos, Peru. Foissner (1997) also mentioned the occurrence of this species in Cabo Frio (Praia do Forte) and Rio de Janeiro, Brazil.

Morphological characterization

Apoamphisiella tihanyiensis had a mean size of 130 x 75 µm (n = 5) in vivo, with a flexible cell body and an ellipsoid shape. A light brownish colouration was observed through the dissection microscope, and under bright field light microscopy under low magnification (i.e. 100X–200X). The cytoplasm showed the same kind of inclusions (i.e. ingested preys) found in A. jurubatiba . When observed at 1,000X magnification under DIC, it showed yellowish cortical granules, which were difficult to observe at lower magnification due to its small size. The single contractile vacuole was ellipsoid, located in the equatorial region of the left margin, with two conspicuous lacunar collector ducts longitudinally.

The anterior frontal cirri set was composed by three cirri arranged in an oblique row located above the anterior arch formed by the paroral membrane. The two posterior frontal cirri and buccal cirrus formed an oblique row as in the neotype population and in A. foissneri . The AZM was conspicuous and occupied about 42% of average body length with 49–60 membranelles. Paroral and endoral membranes virtually intercepted each other, and formed an arch like in the cyrtohymenids. The infundibulum had a small peristomial lip that covered the first three proximal membranelles. Nearby, the postperistomial cirrus was located left of the infundibulum. The left and right ventral rows ended close to the transverse cirri set, which was composed by an oblique row of 6–8 cirri. The leftmost transverse cirri were always to the left of the ventral rows.

On the dorsal surface, there were always three long kineties in the left side and a slightly irregular, but still recognizeable posteriorly shortened kinety, beginning near the equatorial region of cell. In addition, a scattered field of dikinetids was present in the right side of cell. On average, 10 caudal cirri were present and associated to the terminal region of kineties 1, 2 and 4.

FIGURES 29–32:

la tihanyiensis . 29: dorsal view freely motile living specimen der phase contrast; 30: side of protargol

specimen showing ciliature tern; 31: ventral side of

impregnated specimen

ciliature details and nuclear ratus; 32: dorsal side of

impregnated specimen

dorsal ciliature. Dorsal

marked with arabic numbers. rowhead marks field of

dikinetids. Legends: AFC = rior frontal cirri; AZM = zone of membranelles; BC = cal cirrus; eM = endoral brane; LMR = left marginal LVR = left ventral row; Ma = cronuclear nodule; Mi =

cleus; pM = paroral

PpC = postperistomial PFC = posterior frontal RMR = right marginal row; = right ventral row; TC = verse cirri. Scale bars = 10µm.

The nuclear apparatus was composed of two ellipsoid macronuclear nodules, located in the left side of the cell, with the anterior nodule usually placed below the proximal end of the adoral zone of membranelles. Usually, 4–8 micronuclei were observed around the macronuclear nodules. The relative position of both marginal and ventral rows matched the description of the neotype population from Peru.

Figures

FIGURES 10, 11: Apoamphisiella tihanyiensis. 10: ventral side, in vivo; 11: ventral side of protargol impregnated specimen. Legend: CV = contractile vacuole.

FIGURES 12, 13: A. tihanyiensis. 12: dorsal surface of protargol impregnated specimen. Arrow marks the dorsal field of scattered dikinetids; 13: schematic drawing showing general morphology of organism in lateral view.